Begin to refactor for performance.

apm-collector/apm-collector-worker/src/test/java/org/skywalking/apm/collector/worker/span/persistence/SpanSearchWithIdTestCase.java

@@ -18,7 +18,6 @@ import org.skywalking.apm.collector.worker.Const;
 import org.skywalking.apm.collector.worker.segment.SegmentIndex;
 import org.skywalking.apm.collector.worker.segment.mock.SegmentMock;
 import org.skywalking.apm.collector.worker.storage.GetResponseFromEs;
-import org.skywalking.apm.agent.core.context.trace.Span;
 import org.skywalking.apm.agent.core.context.trace.TraceSegment;
 
 import java.util.TimeZone;

apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/client/CollectorClient.java

@@ -10,7 +10,6 @@ import org.apache.http.impl.client.CloseableHttpClient;
 import org.apache.http.impl.client.HttpClients;
 import org.skywalking.apm.agent.core.boot.ServiceManager;
 import org.skywalking.apm.agent.core.conf.Config;
-import org.skywalking.apm.agent.core.context.trace.SegmentsMessage;
 import org.skywalking.apm.agent.core.context.trace.TraceSegment;
 import org.skywalking.apm.agent.core.queue.TraceSegmentProcessQueue;
 import org.skywalking.apm.logging.ILog;

apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/context/AbstractTracerContext.java

 package org.skywalking.apm.agent.core.context;
 
 import org.skywalking.apm.agent.core.context.trace.AbstractSpan;
+import org.skywalking.apm.agent.core.context.trace.SpanType;
 
 /**
  * The <code>AbstractTracerContext</code> represents the tracer context manager.
@@ -14,15 +15,11 @@ public interface AbstractTracerContext {
 
     String getGlobalTraceId();
 
-    AbstractSpan createSpan(String operationName, boolean isLeaf);
-
-    AbstractSpan createSpan(String operationName, long startTime, boolean isLeaf);
+    AbstractSpan createSpan(String operationName, SpanType spanType);
 
     AbstractSpan activeSpan();
 
     void stopSpan(AbstractSpan span);
 
-    void stopSpan(AbstractSpan span, Long endTime);
-
     void dispose();
 }

apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/context/ContextCarrier.java

@@ -5,7 +5,6 @@ import java.util.LinkedList;
 import java.util.List;
 import org.skywalking.apm.agent.core.context.ids.DistributedTraceId;
 import org.skywalking.apm.agent.core.context.ids.PropagatedTraceId;
-import org.skywalking.apm.agent.core.context.trace.Span;
 import org.skywalking.apm.agent.core.context.trace.TraceSegment;
 import org.skywalking.apm.util.StringUtil;
 

apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/context/TracerContext.java

@@ -5,8 +5,6 @@ import java.util.List;
 import org.skywalking.apm.agent.core.boot.ServiceManager;
 import org.skywalking.apm.agent.core.conf.Config;
 import org.skywalking.apm.agent.core.context.trace.AbstractSpan;
-import org.skywalking.apm.agent.core.context.trace.LeafSpan;
-import org.skywalking.apm.agent.core.context.trace.Span;
 import org.skywalking.apm.agent.core.context.trace.TraceSegment;
 import org.skywalking.apm.agent.core.context.trace.TraceSegmentRef;
 import org.skywalking.apm.agent.core.sampling.SamplingService;

apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/context/TracingContext.java

+package org.skywalking.apm.agent.core.context;
+
+import java.util.LinkedList;
+import org.skywalking.apm.agent.core.boot.ServiceManager;
+import org.skywalking.apm.agent.core.conf.Config;
+import org.skywalking.apm.agent.core.context.trace.AbstractSpan;
+import org.skywalking.apm.agent.core.context.trace.AbstractTracingSpan;
+import org.skywalking.apm.agent.core.context.trace.SpanType;
+import org.skywalking.apm.agent.core.context.trace.TraceSegment;
+import org.skywalking.apm.agent.core.dictionary.DictionaryManager;
+import org.skywalking.apm.agent.core.sampling.SamplingService;
+
+/**
+ * @author wusheng
+ */
+public class TracingContext implements AbstractTracerContext {
+    private SamplingService samplingService;
+
+    private TraceSegment segment;
+
+    /**
+     * Active spans stored in a Stack, usually called 'ActiveSpanStack'.
+     * This {@link LinkedList} is the in-memory storage-structure.
+     * <p>
+     * I use {@link LinkedList#removeLast()}, {@link LinkedList#addLast(Object)} and {@link LinkedList#last} instead of
+     * {@link #pop()}, {@link #push(AbstractTracingSpan)}, {@link #peek()}
+     */
+    private LinkedList<AbstractTracingSpan> activeSpanStack = new LinkedList<AbstractTracingSpan>();
+
+    private int spanIdGenerator;
+
+    TracingContext() {
+        this.segment = new TraceSegment(DictionaryManager.getApplicationDictionary().findId(Config.Agent.APPLICATION_CODE));
+        this.spanIdGenerator = 0;
+        if (samplingService == null) {
+            samplingService = ServiceManager.INSTANCE.findService(SamplingService.class);
+        }
+    }
+
+    @Override
+    public void inject(ContextCarrier carrier) {
+
+    }
+
+    @Override
+    public void extract(ContextCarrier carrier) {
+
+    }
+
+    @Override
+    public String getGlobalTraceId() {
+        return null;
+    }
+
+    @Override
+    public AbstractSpan createSpan(String operationName, SpanType spanType) {
+        return null;
+    }
+
+    @Override
+    public AbstractSpan activeSpan() {
+        return null;
+    }
+
+    @Override
+    public void stopSpan(AbstractSpan span) {
+
+    }
+
+    @Override
+    public void dispose() {
+
+    }
+
+    /**
+     * @return the top element of 'ActiveSpanStack', and remove it.
+     */
+    private AbstractTracingSpan pop() {
+        return activeSpanStack.removeLast();
+    }
+
+    /**
+     * Add a new Span at the top of 'ActiveSpanStack'
+     *
+     * @param span
+     */
+    private void push(AbstractTracingSpan span) {
+        activeSpanStack.addLast(span);
+    }
+
+    /**
+     * @return the top element of 'ActiveSpanStack' only.
+     */
+    private AbstractTracingSpan peek() {
+        if (activeSpanStack.isEmpty()) {
+            return null;
+        }
+        return activeSpanStack.getLast();
+    }
+}

apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/context/tag/AbstractTag.java

 package org.skywalking.apm.agent.core.context.tag;
 
 import org.skywalking.apm.agent.core.context.trace.AbstractSpan;
-import org.skywalking.apm.agent.core.context.trace.Span;
 
 /**
  * This is the abstract tag.

apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/context/trace/AbstractSpan.java

 package org.skywalking.apm.agent.core.context.trace;
 
-import java.util.Map;
+import java.util.LinkedList;
+import java.util.List;
+import org.skywalking.apm.agent.core.context.util.KeyValuePair;
+import org.skywalking.apm.agent.core.context.util.ThrowableTransformer;
 
 /**
  * The <code>AbstractSpan</code> represents the span's skeleton,
@@ -8,24 +11,70 @@ import java.util.Map;
  *
  * @author wusheng
  */
-public interface AbstractSpan {
-    AbstractSpan setOperationName(String operationName);
+public abstract class AbstractSpan {
+    protected String operationName;
+    /**
+     * The start time of this Span.
+     */
+    protected long startTime;
+    /**
+     * The end time of this Span.
+     */
+    protected long endTime;
 
-    void setPeerHost(String peerHost);
+    /**
+     * Log is a concept from OpenTracing spec.
+     * <p>
+     * {@see https://github.com/opentracing/specification/blob/master/specification.md#log-structured-data}
+     */
+    protected List<LogDataEntity> logs;
 
-    void setPort(int port);
+    protected AbstractSpan(String operationName) {
+        this.operationName = operationName;
+    }
 
-    void setPeers(String peers);
+    public void start() {
+        this.startTime = System.currentTimeMillis();
+    }
 
-    AbstractSpan setTag(String key, String value);
+    /**
+     * Set a key:value tag on the Span.
+     *
+     * @return this Span instance, for chaining
+     */
+    public abstract AbstractSpan tag(String key, String value);
 
-    AbstractSpan setTag(String key, boolean value);
+    /**
+     * Record an exception event of the current walltime timestamp.
+     *
+     * @param t any subclass of {@link Throwable}, which occurs in this span.
+     * @return the Span, for chaining
+     */
+    public AbstractSpan log(Throwable t) {
+        if (logs == null) {
+            logs = new LinkedList<LogDataEntity>();
+        }
+        logs.add(new LogDataEntity.Builder()
+            .add(new KeyValuePair("event", "error"))
+            .add(new KeyValuePair("error.kind", t.getClass().getName()))
+            .add(new KeyValuePair("message", t.getMessage()))
+            .add(new KeyValuePair("stack", ThrowableTransformer.INSTANCE.convert2String(t, 4000)))
+            .build());
+        return this;
+    }
 
-    AbstractSpan setTag(String key, Integer value);
+    /**
+     * @return true if the actual span is an entry span.
+     */
+    public abstract boolean isEntry();
 
-    AbstractSpan log(Map<String, String> fields);
+    /**
+     * @return true if the actual span is a local span.
+     */
+    public abstract boolean isLocal();
 
-    AbstractSpan log(Throwable t);
-
-    AbstractSpan log(String event);
+    /**
+     * @return true if the actual span is an exit span.
+     */
+    public abstract boolean isExit();
 }

apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/context/trace/AbstractTracingSpan.java

+package org.skywalking.apm.agent.core.context.trace;
+
+import java.util.LinkedList;
+import java.util.List;
+import org.skywalking.apm.agent.core.context.util.KeyValuePair;
+
+/**
+ * The <code>AbstractTracingSpan</code> represents a group of {@link AbstractSpan} implementations,
+ * which belongs a real distributed trace.
+ *
+ * @author wusheng
+ */
+public abstract class AbstractTracingSpan extends AbstractSpan {
+    protected int spanId;
+    protected int parentSpanId;
+    protected List<KeyValuePair> tags;
+
+    protected AbstractTracingSpan(int spanId, int parentSpanId, String operationName) {
+        super(operationName);
+        this.spanId = spanId;
+        this.parentSpanId = parentSpanId;
+    }
+
+    @Override
+    public AbstractTracingSpan tag(String key, String value) {
+        if (tags == null) {
+            tags = new LinkedList<KeyValuePair>();
+        }
+        tags.add(new KeyValuePair(key, value));
+        return this;
+    }
+
+    /**
+     * Finish the active Span.
+     * When it is finished, it will be archived by the given {@link TraceSegment}, which owners it.
+     *
+     * @param owner of the Span.
+     */
+    public void finish(TraceSegment owner) {
+        this.endTime = System.currentTimeMillis();
+        owner.archive(this);
+    }
+}

apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/context/trace/EntrySpan.java

+package org.skywalking.apm.agent.core.context.trace;
+
+/**
+ * The <code>EntrySpan</code> represents a service provider point, such as Tomcat server entrance.
+ *
+ * It is a start point of {@link TraceSegment}, even in a complex application, there maybe have multi entry point,
+ * the <code>EntrySpan</code> only represents the first one.
+ *
+ * But with the last <code>EntrySpan</code>'s tags and logs, which have more details about a service provider.
+ *
+ * @author wusheng
+ */
+public class EntrySpan extends AbstractTracingSpan {
+    private int stackDepth;
+
+    public EntrySpan(int spanId, int parentSpanId, String operationName) {
+        super(spanId, parentSpanId, operationName);
+        this.stackDepth = 0;
+    }
+
+    /**
+     * Set the {@link #startTime}, when the first start, which means the first service provided.
+     */
+    @Override
+    public void start() {
+        if (++stackDepth == 1) {
+            super.start();
+        }
+        clearWhenRestart();
+    }
+
+    @Override
+    public EntrySpan tag(String key, String value) {
+        if (stackDepth == 1) {
+            super.tag(key, value);
+        }
+        return this;
+    }
+
+    @Override
+    public void finish(TraceSegment owner) {
+        if (--stackDepth == 0) {
+            super.finish(owner);
+        }
+    }
+
+    @Override
+    public EntrySpan log(Throwable t) {
+        super.log(t);
+        return this;
+    }
+
+    @Override public boolean isEntry() {
+        return true;
+    }
+
+    @Override public boolean isLocal() {
+        return false;
+    }
+
+    @Override public boolean isExit() {
+        return false;
+    }
+
+    private void clearWhenRestart() {
+        this.logs = null;
+        this.tags = null;
+    }
+}

apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/context/trace/ExitSpan.java

+package org.skywalking.apm.agent.core.context.trace;
+
+/**
+ * The <code>ExitSpan</code> represents a service consumer point, such as Feign, Okhttp client for a Http service.
+ *
+ * It is an exit point or a leaf span(our old name) of trace tree.
+ * In a single rpc call, because of a combination of client libs, there maybe contain multi exit point.
+ *
+ * The <code>ExitSpan</code> only presents the first one.
+ *
+ * @author wusheng
+ */
+public class ExitSpan extends AbstractTracingSpan {
+    private int stackDepth;
+    private String peerPoint;
+
+    public ExitSpan(int spanId, int parentSpanId, String operationName, String peerPoint) {
+        super(spanId, parentSpanId, operationName);
+        this.stackDepth = 0;
+        this.peerPoint = peerPoint;
+    }
+
+    /**
+     * Set the {@link #startTime}, when the first start, which means the first service provided.
+     */
+    @Override
+    public void start() {
+        if (++stackDepth == 1) {
+            super.start();
+        }
+    }
+
+    @Override
+    public ExitSpan tag(String key, String value) {
+        if (stackDepth == 1) {
+            super.tag(key, value);
+        }
+        return this;
+    }
+
+    @Override
+    public void finish(TraceSegment owner) {
+        if (--stackDepth == 0) {
+            super.finish(owner);
+        }
+    }
+
+    @Override
+    public ExitSpan log(Throwable t) {
+        if (stackDepth == 1) {
+            super.log(t);
+        }
+        return this;
+    }
+
+    @Override public boolean isEntry() {
+        return false;
+    }
+
+    @Override public boolean isLocal() {
+        return false;
+    }
+
+    @Override public boolean isExit() {
+        return true;
+    }
+}

apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/context/trace/LeafSpan.java

-package org.skywalking.apm.agent.core.context.trace;
-
-
-/**
- * LeafSpan is a special type of {@link Span}
- *
- * In rpc-client tracing scenario, one component could constitute by many other rpc-client.
- * e.g Feign constitutes by okhttp, apache httpclient, etc.
- *
- * By having leaf concept, no need so many spans for single rpc call.
- *
- * @author wusheng
- */
-public class LeafSpan extends Span {
-    private int stackDepth = 0;
-
-    /**
-     * Create a new span, by given span id and give startTime but no parent span id,
-     * No parent span id means that, this Span is the first span of the {@link TraceSegment}
-     *
-     * @param spanId given by the creator, and must be unique id in the {@link TraceSegment}
-     * @param operationName {@link #operationName}
-     * @param startTime given start time of span
-     */
-    public LeafSpan(int spanId, String operationName, long startTime) {
-        super(spanId, -1, operationName, startTime);
-    }
-
-    /**
-     * Create a new span, by given span id, parent span, operationName and startTime.
-     * This span must belong a {@link TraceSegment}, also is a part of Distributed Trace.
-     *
-     * @param spanId given by the creator, and must be unique id in the {@link TraceSegment}
-     * @param parentSpan {@link Span}
-     * @param operationName {@link #operationName}
-     * @param startTime given start timestamp
-     */
-    public LeafSpan(int spanId, Span parentSpan, String operationName, long startTime) {
-        super(spanId, parentSpan.getSpanId(), operationName, startTime);
-    }
-
-    public void push() {
-        stackDepth++;
-    }
-
-    public void pop() {
-        stackDepth--;
-    }
-
-    public boolean isFinished() {
-        return stackDepth == 0;
-    }
-
-    @Override
-    public boolean isLeaf() {
-        return true;
-    }
-
-    private boolean isInOwnerContext() {
-        return stackDepth == 1;
-    }
-
-    /**
-     * Sets the string name for the logical operation this span represents,
-     * only when this is in context of the leaf span owner.
-     *
-     * @return this Span instance, for chaining
-     */
-    @Override
-    public Span setOperationName(String operationName) {
-        if (isInOwnerContext()) {
-            super.setOperationName(operationName);
-        }
-        return this;
-    }
-
-    /**
-     * Set a key:value tag on the Span,
-     * only when this is in context of the leaf span owner.
-     *
-     * @return this Span instance, for chaining
-     */
-    @Override
-    public final Span setTag(String key, String value) {
-        if (isInOwnerContext()) {
-            super.setTag(key, value);
-        }
-        return this;
-    }
-
-    @Override
-    public final Span setTag(String key, boolean value) {
-        if (isInOwnerContext()) {
-            super.setTag(key, value);
-        }
-        return this;
-    }
-
-    @Override
-    public final Span setTag(String key, Integer value) {
-        if (isInOwnerContext()) {
-            super.setTag(key, value);
-        }
-        return this;
-    }
-}

apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/context/trace/LocalSpan.java

+package org.skywalking.apm.agent.core.context.trace;
+
+/**
+ * The <code>LocalSpan</code> represents a normal tracing point, such as a local method.
+ *
+ * @author wusheng
+ */
+public class LocalSpan extends AbstractTracingSpan {
+
+    public LocalSpan(int spanId, int parentSpanId, String operationName) {
+        super(spanId, parentSpanId, operationName);
+    }
+
+    @Override
+    public LocalSpan tag(String key, String value) {
+        super.tag(key, value);
+        return this;
+    }
+
+    @Override
+    public LocalSpan log(Throwable t) {
+        super.log(t);
+        return this;
+    }
+
+    @Override public boolean isEntry() {
+        return false;
+    }
+
+    @Override public boolean isLocal() {
+        return true;
+    }
+
+    @Override public boolean isExit() {
+        return false;
+    }
+}

apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/context/trace/LogData.java

-package org.skywalking.apm.agent.core.context.trace;
-
-import com.google.gson.annotations.Expose;
-import com.google.gson.annotations.SerializedName;
-import java.util.Collections;
-import java.util.Map;
-
-/**
- * It is a holder of one log record.
- * <p>
- * Created by wusheng on 2017/2/17.
- */
-public class LogData {
-    @Expose
-    @SerializedName(value = "tm")
-    private long time;
-
-    @Expose
-    @SerializedName(value = "fi")
-    private Map<String, String> fields;
-
-    LogData(long time, Map<String, String> fields) {
-        this.time = time;
-        if (fields == null) {
-            throw new NullPointerException();
-        }
-        this.fields = fields;
-    }
-
-    public LogData() {
-    }
-
-    public long getTime() {
-        return time;
-    }
-
-    public Map<String, ?> getFields() {
-        return Collections.unmodifiableMap(fields);
-    }
-
-}

apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/context/trace/LogDataEntity.java

+package org.skywalking.apm.agent.core.context.trace;
+
+import java.util.LinkedList;
+import java.util.List;
+import org.skywalking.apm.agent.core.context.util.KeyValuePair;
+
+/**
+ * The <code>LogDataEntity</code> represents a collection of {@link KeyValuePair},
+ * contains several fields of a logging operation.
+ *
+ * @author wusheng
+ */
+public class LogDataEntity {
+    protected List<KeyValuePair> logs;
+
+    private LogDataEntity(List<KeyValuePair> logs) {
+        this.logs = logs;
+    }
+
+    public List<KeyValuePair> getLogs() {
+        return logs;
+    }
+
+    public static class Builder {
+        protected List<KeyValuePair> logs;
+
+        public Builder() {
+            logs = new LinkedList<KeyValuePair>();
+        }
+
+        public Builder add(KeyValuePair... fields){
+            for (KeyValuePair field : fields) {
+                logs.add(field);
+            }
+            return this;
+        }
+
+        public LogDataEntity build(){
+            return new LogDataEntity(logs);
+        }
+    }
+}

apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/context/trace/NoopSpan.java

 package org.skywalking.apm.agent.core.context.trace;
 
-import java.util.Map;
 import org.skywalking.apm.agent.core.context.IgnoredTracerContext;
 
 /**
@@ -9,55 +8,39 @@ import org.skywalking.apm.agent.core.context.IgnoredTracerContext;
  *
  * @author wusheng
  */
-public class NoopSpan implements AbstractSpan {
-    @Override
-    public AbstractSpan setOperationName(String operationName) {
-        return this;
-    }
-
-    @Override
-    public void setPeerHost(String peerHost) {
-
+public class NoopSpan extends AbstractSpan {
+    public NoopSpan() {
+        super(null);
     }
 
     @Override
-    public void setPort(int port) {
-
+    public void start() {
+        super.start();
     }
 
     @Override
-    public void setPeers(String peers) {
-
+    public AbstractSpan log(Throwable t) {
+        return super.log(t);
     }
 
-    @Override
-    public AbstractSpan setTag(String key, String value) {
-        return this;
-    }
+    public void finish(){
 
-    @Override
-    public AbstractSpan setTag(String key, boolean value) {
-        return this;
     }
 
     @Override
-    public AbstractSpan setTag(String key, Integer value) {
-        return this;
+    public AbstractSpan tag(String key, String value) {
+        return null;
     }
 
-    @Override
-    public AbstractSpan log(Map<String, String> fields) {
-        return this;
+    @Override public boolean isEntry() {
+        return false;
     }
 
-    @Override
-    public AbstractSpan log(Throwable t) {
-        return this;
+    @Override public boolean isLocal() {
+        return false;
     }
 
-    @Override
-    public AbstractSpan log(String event) {
-        return this;
+    @Override public boolean isExit() {
+        return false;
     }
-
 }

apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/context/trace/SegmentsMessage.java

-package org.skywalking.apm.agent.core.context.trace;
-
-import com.google.gson.Gson;
-import java.util.Collections;
-import java.util.LinkedList;
-import java.util.List;
-
-/**
- * The <code>SegmentsMessage</code> is a set of {@link TraceSegment},
- * this set provides a container, when several {@link TraceSegment}s are going to uplink to server.
- *
- * @author wusheng
- */
-public class SegmentsMessage {
-    private List<TraceSegment> segments;
-
-    public SegmentsMessage() {
-        segments = new LinkedList<TraceSegment>();
-    }
-
-    public void append(TraceSegment segment) {
-        this.segments.add(segment);
-    }
-
-    public List<TraceSegment> getSegments() {
-        return Collections.unmodifiableList(segments);
-    }
-
-    /**
-     * This serialization mechanism started from 3.1, it is similar to network package.
-     * The data protocol is
-     *
-     * segment1.json.length + ' '(one blank space) + segment1.json
-     * + segment2.json.length + ' '(one blank space) + segment2.json
-     * + etc.
-     *
-     * @param gson the serializer for {@link TraceSegment}
-     * @return the string represents the <code>SegmentMessage</code>
-     */
-    public String serialize(Gson gson) {
-        StringBuilder buffer = new StringBuilder();
-        for (TraceSegment segment : segments) {
-            String segmentJson = gson.toJson(segment);
-            buffer.append(segmentJson.length()).append(' ').append(segmentJson);
-        }
-        return buffer.toString();
-    }
-}

apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/context/trace/Span.java

-package org.skywalking.apm.agent.core.context.trace;
-
-import com.google.gson.Gson;
-import com.google.gson.GsonBuilder;
-import com.google.gson.JsonObject;
-import com.google.gson.TypeAdapter;
-import com.google.gson.annotations.JsonAdapter;
-import com.google.gson.stream.JsonReader;
-import com.google.gson.stream.JsonWriter;
-import java.io.IOException;
-import java.util.Collections;
-import java.util.HashMap;
-import java.util.LinkedList;
-import java.util.List;
-import java.util.Map;
-import org.skywalking.apm.agent.core.context.tag.BooleanTagItem;
-import org.skywalking.apm.agent.core.context.tag.IntTagItem;
-import org.skywalking.apm.agent.core.context.tag.StringTagItem;
-import org.skywalking.apm.agent.core.context.util.ThrowableTransformer;
-import org.skywalking.apm.util.StringUtil;
-
-/**
- * Span is a concept from OpenTracing Spec, also from Google Dapper Paper.
- * Traces in OpenTracing are defined implicitly by their Spans.
- * <p>
- * Know more things about span concept:
- * {@see https://github.com/opentracing/specification/blob/master/specification.md#the-opentracing-data-model}
- * <p>
- * Created by wusheng on 2017/2/17.
- */
-@JsonAdapter(Span.Serializer.class)
-public class Span implements AbstractSpan {
-    private static Gson SERIALIZATION_GSON = new GsonBuilder().excludeFieldsWithoutExposeAnnotation().create();
-
-    private int spanId;
-    private int parentSpanId;
-
-    /**
-     * The start time of this Span.
-     */
-    private long startTime;
-
-    /**
-     * The end time of this Span.
-     */
-    private long endTime;
-
-    /**
-     * The operation name ot this Span.
-     * If you want to know, how to set an operation name,
-     * {@see https://github.com/opentracing/specification/blob/master/specification.md#start-a-new-span}
-     */
-    private String operationName;
-
-    /**
-     * {@link #peerHost}, {@link #port} and {@link #peers} were part of tags,
-     * independence them from tags for better performance and gc.
-     */
-    private String peerHost;
-
-    private int port;
-
-    private String peers;
-
-    /**
-     * Tag is a concept from OpenTracing spec.
-     * <p>
-     * {@see https://github.com/opentracing/specification/blob/master/specification.md#set-a-span-tag}
-     */
-    private List<StringTagItem> tagsWithStr;
-
-    private List<BooleanTagItem> tagsWithBool;
-
-    private List<IntTagItem> tagsWithInt;
-
-    /**
-     * Log is a concept from OpenTracing spec.
-     * <p>
-     * {@see https://github.com/opentracing/specification/blob/master/specification.md#log-structured-data}
-     */
-    private List<LogData> logs;
-
-    /**
-     * Create a new span, by given span id, parent span id and operationName.
-     * This span must belong a {@link TraceSegment}, also is a part of Distributed Trace.
-     *
-     * @param spanId given by the creator, and must be unique id in the {@link TraceSegment}
-     * @param parentSpanId given by the creator, and must be an existed span id in the {@link TraceSegment}. Value -1
-     * means no parent span if this {@link TraceSegment}.
-     * @param operationName {@link #operationName}
-     */
-    protected Span(int spanId, int parentSpanId, String operationName) {
-        this(spanId, parentSpanId, operationName, System.currentTimeMillis());
-    }
-
-    /**
-     * Create a new span, by given span id, parent span id, operationName and startTime.
-     * This span must belong a {@link TraceSegment}, also is a part of Distributed Trace.
-     *
-     * @param spanId given by the creator, and must be unique id in the {@link TraceSegment}
-     * @param parentSpanId given by the creator, and must be an existed span id in the {@link TraceSegment}. Value -1
-     * means no parent span if this {@link TraceSegment}.
-     * @param operationName {@link #operationName}
-     * @param startTime given start timestamp.
-     */
-    protected Span(int spanId, int parentSpanId, String operationName, long startTime) {
-        this();
-        this.spanId = spanId;
-        this.parentSpanId = parentSpanId;
-        this.startTime = startTime;
-        this.setOperationName(operationName);
-    }
-
-    /**
-     * Create a new span, by given span id and no parent span id.
-     * No parent span id means that, this Span is the first span of the {@link TraceSegment}
-     *
-     * @param spanId given by the creator, and must be unique id in the {@link TraceSegment}
-     * @param operationName {@link #operationName}
-     */
-    public Span(int spanId, String operationName) {
-        this(spanId, -1, operationName);
-    }
-
-    /**
-     * Create a new span, by given span id and give startTime but no parent span id,
-     * No parent span id means that, this Span is the first span of the {@link TraceSegment}
-     *
-     * @param spanId given by the creator, and must be unique id in the {@link TraceSegment}
-     * @param operationName {@link #operationName}
-     * @param startTime given start time of span
-     */
-    public Span(int spanId, String operationName, long startTime) {
-        this(spanId, -1, operationName, startTime);
-    }
-
-    /**
-     * Create a new span, by given span id and given parent {@link Span}.
-     *
-     * @param spanId given by the creator, and must be unique id in the {@link TraceSegment}
-     * @param parentSpan {@link Span}
-     * @param operationName {@link #operationName}
-     */
-    public Span(int spanId, Span parentSpan, String operationName) {
-        this(spanId, parentSpan.spanId, operationName, System.currentTimeMillis());
-    }
-
-    /**
-     * Create a new span, by given span id, parent span, operationName and startTime.
-     * This span must belong a {@link TraceSegment}, also is a part of Distributed Trace.
-     *
-     * @param spanId given by the creator, and must be unique id in the {@link TraceSegment}
-     * @param parentSpan {@link Span}
-     * @param operationName {@link #operationName}
-     * @param startTime given start timestamp
-     */
-    public Span(int spanId, Span parentSpan, String operationName, long startTime) {
-        this(spanId, parentSpan.spanId, operationName, startTime);
-    }
-
-    /**
-     * Create a new/empty span.
-     */
-    public Span() {
-    }
-
-    /**
-     * Finish the active Span.
-     * When it is finished, it will be archived by the given {@link TraceSegment}, which owners it.
-     *
-     * @param owner of the Span.
-     */
-    public void finish(TraceSegment owner) {
-        this.finish(owner, System.currentTimeMillis());
-    }
-
-    /**
-     * Finish the active Span.
-     * When it is finished, it will be archived by the given {@link TraceSegment}, which owners it.
-     * At the same out, set the {@link #endTime} as the given endTime
-     *
-     * @param owner of the Span.
-     * @param endTime of the Span.
-     */
-    public void finish(TraceSegment owner, long endTime) {
-        this.endTime = endTime;
-        owner.archive(this);
-    }
-
-    /**
-     * Set the string name for the logical operation this span represents.
-     *
-     * @return this Span instance, for chaining
-     */
-    public AbstractSpan setOperationName(String operationName) {
-        this.operationName = operationName;
-        return this;
-    }
-
-    /**
-     * Set a key:value tag on the Span.
-     *
-     * @return this Span instance, for chaining
-     */
-    public Span setTag(String key, String value) {
-        if (tagsWithStr == null) {
-            tagsWithStr = new LinkedList<StringTagItem>();
-        }
-        tagsWithStr.add(new StringTagItem(key, value));
-        return this;
-    }
-
-    public Span setTag(String key, boolean value) {
-        if (tagsWithBool == null) {
-            tagsWithBool = new LinkedList<BooleanTagItem>();
-        }
-        tagsWithBool.add(new BooleanTagItem(key, value));
-        return this;
-    }
-
-    public Span setTag(String key, Integer value) {
-        if (tagsWithInt == null) {
-            tagsWithInt = new LinkedList<IntTagItem>();
-        }
-        tagsWithInt.add(new IntTagItem(key, value));
-        return this;
-    }
-
-    /**
-     * This method is from opentracing-java. {@see https://github.com/opentracing/opentracing-java/blob/release-0.20.9/opentracing-api/src/main/java/io/opentracing/Span.java#L91}
-     * <p> Log key:value pairs to the Span with the current walltime timestamp. <p> <p><strong>CAUTIONARY NOTE:</strong>
-     * not all Tracer implementations support key:value log fields end-to-end. Caveat emptor. <p> <p>A contrived example
-     * (using Guava, which is not required):
-     * <pre>{@code
-     * span.log(
-     * ImmutableMap.Builder<String, Object>()
-     * .put("event", "soft error")
-     * .put("type", "cache timeout")
-     * .put("waited.millis", 1500)
-     * .build());
-     * }</pre>
-     *
-     * @param fields key:value log fields. Tracer implementations should support String, numeric, and boolean values;
-     * some may also support arbitrary Objects.
-     * @return the Span, for chaining
-     * @see Span#log(String)
-     */
-    public Span log(Map<String, String> fields) {
-        if (logs == null) {
-            logs = new LinkedList<LogData>();
-        }
-        logs.add(new LogData(System.currentTimeMillis(), fields));
-        return this;
-    }
-
-    /**
-     * Record an exception event of the current walltime timestamp.
-     *
-     * @param t any subclass of {@link Throwable}, which occurs in this span.
-     * @return the Span, for chaining
-     */
-    public Span log(Throwable t) {
-        Map<String, String> exceptionFields = new HashMap<String, String>();
-        exceptionFields.put("event", "error");
-        exceptionFields.put("error.kind", t.getClass().getName());
-        exceptionFields.put("message", t.getMessage());
-        exceptionFields.put("stack", ThrowableTransformer.INSTANCE.convert2String(t, 4000));
-
-        return log(exceptionFields);
-    }
-
-    /**
-     * This method is from opentracing-java. {@see https://github.com/opentracing/opentracing-java/blob/release-0.20.9/opentracing-api/src/main/java/io/opentracing/Span.java#L120}
-     * <p> Record an event at the current walltime timestamp. <p> Shorthand for <p>
-     * <pre>{@code
-     * span.log(Collections.singletonMap("event", event));
-     * }</pre>
-     *
-     * @param event the event value; often a stable identifier for a moment in the Span lifecycle
-     * @return the Span, for chaining
-     */
-    public Span log(String event) {
-        log(Collections.singletonMap("event", event));
-        return this;
-    }
-
-    public int getSpanId() {
-        return spanId;
-    }
-
-    public int getParentSpanId() {
-        return parentSpanId;
-    }
-
-    public long getStartTime() {
-        return startTime;
-    }
-
-    public long getEndTime() {
-        return endTime;
-    }
-
-    public String getOperationName() {
-        return operationName;
-    }
-
-    public boolean isLeaf() {
-        return false;
-    }
-
-    public String getPeerHost() {
-        return peerHost;
-    }
-
-    public int getPort() {
-        return port;
-    }
-
-    public String getPeers() {
-        return peers;
-    }
-
-    public void setPeerHost(String peerHost) {
-        this.peerHost = peerHost;
-    }
-
-    public void setPort(int port) {
-        this.port = port;
-    }
-
-    public void setPeers(String peers) {
-        this.peers = peers;
-    }
-
-    @Override
-    public String toString() {
-        return "Span{" +
-            "spanId=" + spanId +
-            ", parentSpanId=" + parentSpanId +
-            ", startTime=" + startTime +
-            ", operationName='" + operationName + '\'' +
-            '}';
-    }
-
-    public static class Serializer extends TypeAdapter<Span> {
-        @Override
-        public void write(JsonWriter out, Span span) throws IOException {
-            out.beginObject();
-            out.name("si").value(span.spanId);
-            out.name("ps").value(span.parentSpanId);
-            out.name("st").value(span.startTime);
-            out.name("et").value(span.endTime);
-            out.name("on").value(span.operationName);
-
-            this.writeTags(out, span);
-
-            if (span.logs != null) {
-                out.name("logs").jsonValue(SERIALIZATION_GSON.toJson(span.logs));
-            }
-
-            out.endObject();
-        }
-
-        public void writeTags(JsonWriter out, Span span) throws IOException {
-            JsonObject tagWithStr = null;
-            JsonObject tagWithInt = null;
-            JsonObject tagWithBool = null;
-            if (!StringUtil.isEmpty(span.peerHost)) {
-                tagWithStr = new JsonObject();
-                tagWithStr.addProperty("peer.host", span.peerHost);
-                tagWithInt = new JsonObject();
-                tagWithInt.addProperty("peer.port", span.port);
-            } else if (!StringUtil.isEmpty(span.peers)) {
-                tagWithStr = new JsonObject();
-                tagWithStr.addProperty("peers", span.peers);
-            } else if (span.tagsWithStr != null) {
-                tagWithStr = new JsonObject();
-            }
-
-            if (span.tagsWithStr != null) {
-                for (StringTagItem item : span.tagsWithStr) {
-                    tagWithStr.addProperty(item.getKey(), item.getValue());
-                }
-            }
-            if (span.tagsWithInt != null) {
-                if (tagWithInt != null) {
-                    tagWithInt = new JsonObject();
-                }
-                for (IntTagItem item : span.tagsWithInt) {
-                    tagWithInt.addProperty(item.getKey(), item.getValue());
-                }
-            }
-            if (span.tagsWithBool != null) {
-                tagWithBool = new JsonObject();
-                for (BooleanTagItem item : span.tagsWithBool) {
-                    tagWithBool.addProperty(item.getKey(), item.getValue());
-                }
-            }
-
-            if (tagWithStr != null) {
-                out.name("ts").jsonValue(tagWithStr.toString());
-            }
-            if (tagWithInt != null) {
-                out.name("ti").jsonValue(tagWithInt.toString());
-            }
-            if (tagWithBool != null) {
-                out.name("tb").jsonValue(tagWithBool.toString());
-            }
-        }
-
-        @Override
-        public Span read(JsonReader in) throws IOException {
-            throw new IOException("Can't deserialize span at agent side for performance consideration");
-        }
-    }
-}

apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/context/trace/SpanType.java

+package org.skywalking.apm.agent.core.context.trace;
+
+/**
+ * @author wusheng
+ */
+public enum SpanType {
+    ENTRY,
+    EXIT,
+    LOCAL;
+}

apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/context/trace/TraceSegment.java

 package org.skywalking.apm.agent.core.context.trace;
 
-import com.google.gson.annotations.Expose;
-import com.google.gson.annotations.SerializedName;
 import java.util.Collections;
 import java.util.LinkedList;
 import java.util.List;
@@ -26,22 +24,16 @@ public class TraceSegment {
      * The id of this trace segment.
      * Every segment has its unique-global-id.
      */
-    @Expose
-    @SerializedName(value = "ts")
     private String traceSegmentId;
 
     /**
      * The start time of this trace segment.
      */
-    @Expose
-    @SerializedName(value = "st")
     private long startTime;
 
     /**
      * The end time of this trace segment.
      */
-    @Expose
-    @SerializedName(value = "et")
     private long endTime;
 
     /**
@@ -50,8 +42,6 @@ public class TraceSegment {
      * but if this segment is a start span of batch process, the segment faces multi parents,
      * at this moment, we use this {@link #refs} to link them.
      */
-    @Expose
-    @SerializedName(value = "rs")
     private List<TraceSegmentRef> refs;
 
     /**
@@ -59,19 +49,15 @@ public class TraceSegment {
      * They all have finished.
      * All active spans are hold and controlled by "skywalking-api" module.
      */
-    @Expose
-    @SerializedName(value = "ss")
-    private List<Span> spans;
+    private List<AbstractTracingSpan> spans;
 
     /**
-     * The <code>applicationCode</code> represents a name of current application/JVM and indicates which is business
+     * The <code>applicationId</code> represents a name of current application/JVM and indicates which is business
      * role in the cluster.
      * <p>
      * e.g. account_app, billing_app
      */
-    @Expose
-    @SerializedName(value = "ac")
-    private String applicationCode;
+    private int applicationId;
 
     /**
      * The <code>relatedGlobalTraces</code> represent a set of all related trace. Most time it contains only one
@@ -86,18 +72,16 @@ public class TraceSegment {
      * <code>relatedGlobalTraces</code> targets this {@link TraceSegment}'s related call chain, a call chain contains
      * multi {@link TraceSegment}s, only using {@link #refs} is not enough for analysis and ui.
      */
-    @Expose
-    @SerializedName(value = "gt")
     private DistributedTraceIds relatedGlobalTraces;
 
     private boolean ignore = false;
 
     /**
-     * Create a trace segment, by the given applicationCode.
+     * Create a trace segment, by the given applicationId.
      */
-    public TraceSegment(String applicationCode) {
+    public TraceSegment(int applicationId) {
         this();
-        this.applicationCode = applicationCode;
+        this.applicationId = applicationId;
     }
 
     /**
@@ -108,7 +92,7 @@ public class TraceSegment {
     public TraceSegment() {
         this.startTime = System.currentTimeMillis();
         this.traceSegmentId = GlobalIdGenerator.generate(ID_TYPE);
-        this.spans = new LinkedList<Span>();
+        this.spans = new LinkedList<AbstractTracingSpan>();
         this.relatedGlobalTraces = new DistributedTraceIds();
         this.relatedGlobalTraces.append(new NewDistributedTraceId());
     }
@@ -142,12 +126,12 @@ public class TraceSegment {
     }
 
     /**
-     * After {@link Span} is finished, as be controller by "skywalking-api" module,
+     * After {@link AbstractSpan} is finished, as be controller by "skywalking-api" module,
      * notify the {@link TraceSegment} to archive it.
      *
      * @param finishedSpan
      */
-    public void archive(Span finishedSpan) {
+    public void archive(AbstractTracingSpan finishedSpan) {
         spans.add(finishedSpan);
     }
 
@@ -173,13 +157,6 @@ public class TraceSegment {
         return endTime;
     }
 
-    public List<TraceSegmentRef> getRefs() {
-        if (refs == null) {
-            return null;
-        }
-        return Collections.unmodifiableList(refs);
-    }
-
     public boolean hasRef() {
         return !(refs == null || refs.size() == 0);
     }
@@ -192,14 +169,6 @@ public class TraceSegment {
         return this.spans != null && this.spans.size() == 1;
     }
 
-    public List<Span> getSpans() {
-        return Collections.unmodifiableList(spans);
-    }
-
-    public String getApplicationCode() {
-        return applicationCode;
-    }
-
     public boolean isIgnore() {
         return ignore;
     }
@@ -216,7 +185,7 @@ public class TraceSegment {
             ", endTime=" + endTime +
             ", refs=" + refs +
             ", spans=" + spans +
-            ", applicationCode='" + applicationCode + '\'' +
+            ", applicationId='" + applicationId + '\'' +
             ", relatedGlobalTraces=" + relatedGlobalTraces +
             '}';
     }

apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/context/trace/TraceSegmentRef.java

 package org.skywalking.apm.agent.core.context.trace;
 
-import com.google.gson.annotations.Expose;
-import com.google.gson.annotations.SerializedName;
-import org.skywalking.apm.agent.core.context.tag.Tags;
-
 /**
  * {@link TraceSegmentRef} is like a pointer, which ref to another {@link TraceSegment},
  * use {@link #spanId} point to the exact span of the ref {@link TraceSegment}.
@@ -14,29 +10,12 @@ public class TraceSegmentRef {
     /**
      * {@link TraceSegment#traceSegmentId}
      */
-    @Expose
-    @SerializedName(value = "ts")
     private String traceSegmentId;
 
-    /**
-     * {@link Span#spanId}
-     */
-    @Expose
-    @SerializedName(value = "si")
     private int spanId = -1;
 
-    /**
-     * {@link TraceSegment#applicationCode}
-     */
-    @Expose
-    @SerializedName(value = "ac")
     private String applicationCode;
 
-    /**
-     * {@link Tags#PEER_HOST}
-     */
-    @Expose
-    @SerializedName(value = "ph")
     private String peerHost;
 
     /**

apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/context/util/KeyValuePair.java

+package org.skywalking.apm.agent.core.context.util;
+
+/**
+ * The <code>KeyValuePair</code> represents a object which contains a string key and a string value.
+ *
+ * @author wusheng
+ */
+public class KeyValuePair {
+    private String key;
+    private String value;
+
+    public KeyValuePair(String key, String value) {
+        this.key = key;
+        this.value = value;
+    }
+
+    public String getKey() {
+        return key;
+    }
+
+    public String getValue() {
+        return value;
+    }
+}

apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/dictionary/ApplicationDictionary.java

+package org.skywalking.apm.agent.core.dictionary;
+
+/**
+ * Map of application id to application code, which is from the collector side.
+ *
+ * @author wusheng
+ */
+public enum ApplicationDictionary {
+    INSTANCE;
+
+    public int findId(String applicationCode) {
+
+    }
+}

apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/dictionary/DictionaryManager.java

+package org.skywalking.apm.agent.core.dictionary;
+
+/**
+ * @author wusheng
+ */
+public class DictionaryManager {
+    /**
+     * @return {@link ApplicationDictionary} to find applicationId
+     */
+    public static ApplicationDictionary getApplicationDictionary(){
+        return ApplicationDictionary.INSTANCE;
+    }
+}

apm-sniffer/apm-agent-core/src/test/java/org/skywalking/apm/agent/core/context/trace/LeafSpanTestCase.java

@@ -2,7 +2,6 @@ package org.skywalking.apm.agent.core.context.trace;
 
 import org.junit.Assert;
 import org.junit.Test;
-import org.skywalking.apm.agent.core.context.trace.LeafSpan;
 import org.skywalking.apm.agent.core.tags.BooleanTagReader;
 import org.skywalking.apm.agent.core.tags.IntTagReader;
 import org.skywalking.apm.agent.core.tags.StringTagReader;

apm-sniffer/apm-agent-core/src/test/java/org/skywalking/apm/agent/core/context/trace/SpanTestCase.java

@@ -6,9 +6,6 @@ import org.junit.Assert;
 import org.junit.Test;
 import org.skywalking.apm.agent.core.tags.BooleanTagReader;
 import org.skywalking.apm.agent.core.tags.StringTagReader;
-import org.skywalking.apm.agent.core.context.trace.LogData;
-import org.skywalking.apm.agent.core.context.trace.Span;
-import org.skywalking.apm.agent.core.context.trace.TraceSegment;
 import org.skywalking.apm.agent.core.context.tag.Tags;
 
 /**

apm-sniffer/apm-agent-core/src/test/java/org/skywalking/apm/agent/core/context/trace/TraceSegmentTestCase.java

@@ -18,7 +18,7 @@ public class TraceSegmentTestCase {
 
         Assert.assertTrue(segment.getTraceSegmentId().startsWith("Segment"));
         Assert.assertTrue(segment.getStartTime() > 0);
-        Assert.assertEquals("billing_app", segment.getApplicationCode());
+        Assert.assertEquals("billing_app", segment.getApplicationId());
     }
 
     @Test

apm-sniffer/apm-agent-core/src/test/java/org/skywalking/apm/agent/core/tags/BooleanTagReader.java

@@ -2,7 +2,6 @@ package org.skywalking.apm.agent.core.tags;
 
 import java.lang.reflect.Field;
 import java.util.List;
-import org.skywalking.apm.agent.core.context.trace.Span;
 import org.skywalking.apm.agent.core.context.tag.BooleanTag;
 import org.skywalking.apm.agent.core.context.tag.BooleanTagItem;
 

apm-sniffer/apm-agent-core/src/test/java/org/skywalking/apm/agent/core/tags/IntTagReader.java

@@ -2,7 +2,6 @@ package org.skywalking.apm.agent.core.tags;
 
 import java.lang.reflect.Field;
 import java.util.List;
-import org.skywalking.apm.agent.core.context.trace.Span;
 import org.skywalking.apm.agent.core.context.tag.IntTag;
 import org.skywalking.apm.agent.core.context.tag.IntTagItem;
 

apm-sniffer/apm-agent-core/src/test/java/org/skywalking/apm/agent/core/tags/StringTagReader.java

@@ -2,7 +2,6 @@ package org.skywalking.apm.agent.core.tags;
 
 import java.lang.reflect.Field;
 import java.util.List;
-import org.skywalking.apm.agent.core.context.trace.Span;
 import org.skywalking.apm.agent.core.context.tag.StringTag;
 import org.skywalking.apm.agent.core.context.tag.StringTagItem;
 

apm-sniffer/apm-agent/pom.xml

@@ -148,7 +148,6 @@
                                     <exclude>org.apache.httpcomponents:*</exclude>
                                     <exclude>commons-logging:*</exclude>
                                     <exclude>commons-codec:*</exclude>
-                                    <exclude>*:gson</exclude>
                                 </excludes>
                             </artifactSet>
                             <relocations>

apm-sniffer/apm-sdk-plugin/dubbo-plugin/src/test/java/org/skywalking/apm/plugin/dubbo/DubboInterceptorTest.java

@@ -27,8 +27,6 @@ import org.skywalking.apm.sniffer.mock.context.MockTracerContextListener;
 import org.skywalking.apm.sniffer.mock.context.SegmentAssert;
 import org.skywalking.apm.sniffer.mock.trace.SpanLogReader;
 import org.skywalking.apm.sniffer.mock.trace.tags.StringTagReader;
-import org.skywalking.apm.agent.core.context.trace.LogData;
-import org.skywalking.apm.agent.core.context.trace.Span;
 import org.skywalking.apm.agent.core.context.trace.TraceSegment;
 import org.skywalking.apm.agent.core.context.trace.TraceSegmentRef;
 import org.skywalking.apm.agent.core.context.tag.Tags;

apm-sniffer/apm-sdk-plugin/feign-default-http-9.x-plugin/src/main/java/org/skywalking/apm/plugin/feign/http/v9/DefaultHttpClientInterceptor.java

@@ -16,7 +16,6 @@ import org.skywalking.apm.agent.core.context.ContextCarrier;
 import org.skywalking.apm.agent.core.context.ContextManager;
 import org.skywalking.apm.agent.core.context.tag.Tags;
 import org.skywalking.apm.agent.core.context.trace.AbstractSpan;
-import org.skywalking.apm.agent.core.context.trace.Span;
 import org.skywalking.apm.agent.core.plugin.interceptor.EnhancedClassInstanceContext;
 import org.skywalking.apm.agent.core.plugin.interceptor.enhance.InstanceMethodInvokeContext;
 import org.skywalking.apm.agent.core.plugin.interceptor.enhance.InstanceMethodsAroundInterceptor;

apm-sniffer/apm-sdk-plugin/feign-default-http-9.x-plugin/src/test/java/org/skywalking/apm/plugin/feign/http/v9/DefaultHttpClientInterceptorTest.java

@@ -22,7 +22,6 @@ import org.skywalking.apm.sniffer.mock.context.SegmentAssert;
 import org.skywalking.apm.sniffer.mock.trace.SpanLogReader;
 import org.skywalking.apm.sniffer.mock.trace.tags.BooleanTagReader;
 import org.skywalking.apm.sniffer.mock.trace.tags.StringTagReader;
-import org.skywalking.apm.agent.core.context.trace.Span;
 import org.skywalking.apm.agent.core.context.trace.TraceSegment;
 import org.skywalking.apm.agent.core.context.tag.Tags;
 

apm-sniffer/apm-sdk-plugin/httpClient-4.x-plugin/src/test/java/org/skywalking/apm/plugin/httpClient/v4/HttpClientExecuteInterceptorTest.java

@@ -18,8 +18,6 @@ import org.skywalking.apm.sniffer.mock.context.MockTracerContextListener;
 import org.skywalking.apm.sniffer.mock.context.SegmentAssert;
 import org.skywalking.apm.sniffer.mock.trace.tags.BooleanTagReader;
 import org.skywalking.apm.sniffer.mock.trace.tags.StringTagReader;
-import org.skywalking.apm.agent.core.context.trace.LogData;
-import org.skywalking.apm.agent.core.context.trace.Span;
 import org.skywalking.apm.agent.core.context.trace.TraceSegment;
 import org.skywalking.apm.agent.core.context.tag.Tags;
 

apm-sniffer/apm-sdk-plugin/jdbc-plugin/src/main/java/org/skywalking/apm/plugin/jdbc/CallableStatementTracing.java

@@ -4,7 +4,6 @@ import java.sql.SQLException;
 import org.skywalking.apm.agent.core.context.ContextManager;
 import org.skywalking.apm.agent.core.context.tag.Tags;
 import org.skywalking.apm.agent.core.context.trace.AbstractSpan;
-import org.skywalking.apm.agent.core.context.trace.Span;
 import org.skywalking.apm.util.StringUtil;
 
 /**

apm-sniffer/apm-sdk-plugin/jdbc-plugin/src/main/java/org/skywalking/apm/plugin/jdbc/ConnectionTracing.java

@@ -3,7 +3,6 @@ package org.skywalking.apm.plugin.jdbc;
 import org.skywalking.apm.agent.core.context.ContextManager;
 import org.skywalking.apm.agent.core.context.trace.AbstractSpan;
 import org.skywalking.apm.util.StringUtil;
-import org.skywalking.apm.agent.core.context.trace.Span;
 import org.skywalking.apm.agent.core.context.tag.Tags;
 
 import java.sql.SQLException;

apm-sniffer/apm-sdk-plugin/jdbc-plugin/src/main/java/org/skywalking/apm/plugin/jdbc/PreparedStatementTracing.java

@@ -4,7 +4,6 @@ import java.sql.SQLException;
 import org.skywalking.apm.agent.core.context.ContextManager;
 import org.skywalking.apm.agent.core.context.tag.Tags;
 import org.skywalking.apm.agent.core.context.trace.AbstractSpan;
-import org.skywalking.apm.agent.core.context.trace.Span;
 import org.skywalking.apm.util.StringUtil;
 
 /**

apm-sniffer/apm-sdk-plugin/jdbc-plugin/src/main/java/org/skywalking/apm/plugin/jdbc/StatementTracing.java

@@ -4,7 +4,6 @@ import java.sql.SQLException;
 import org.skywalking.apm.agent.core.context.ContextManager;
 import org.skywalking.apm.agent.core.context.tag.Tags;
 import org.skywalking.apm.agent.core.context.trace.AbstractSpan;
-import org.skywalking.apm.agent.core.context.trace.Span;
 import org.skywalking.apm.util.StringUtil;
 
 /**

apm-sniffer/apm-sdk-plugin/jdbc-plugin/src/test/java/org/skywalking/apm/plugin/jdbc/AbstractStatementTest.java

@@ -5,8 +5,6 @@ import java.util.List;
 import org.hamcrest.CoreMatchers;
 import org.skywalking.apm.sniffer.mock.context.MockTracerContextListener;
 import org.skywalking.apm.sniffer.mock.trace.tags.StringTagReader;
-import org.skywalking.apm.agent.core.context.trace.LogData;
-import org.skywalking.apm.agent.core.context.trace.Span;
 import org.skywalking.apm.agent.core.context.tag.Tags;
 
 import java.sql.SQLException;

apm-sniffer/apm-sdk-plugin/jdbc-plugin/src/test/java/org/skywalking/apm/plugin/jdbc/SWCallableStatementTest.java

 package org.skywalking.apm.plugin.jdbc;
 
 import com.mysql.cj.api.jdbc.JdbcConnection;
-import java.lang.reflect.Field;
 import java.util.List;
 import org.hamcrest.CoreMatchers;
 import org.junit.After;
@@ -16,8 +15,6 @@ import org.skywalking.apm.agent.core.boot.ServiceManager;
 import org.skywalking.apm.agent.core.context.TracerContext;
 import org.skywalking.apm.sniffer.mock.context.MockTracerContextListener;
 import org.skywalking.apm.sniffer.mock.context.SegmentAssert;
-import org.skywalking.apm.agent.core.context.trace.LogData;
-import org.skywalking.apm.agent.core.context.trace.Span;
 import org.skywalking.apm.agent.core.context.trace.TraceSegment;
 
 import java.io.InputStream;

apm-sniffer/apm-sdk-plugin/jdbc-plugin/src/test/java/org/skywalking/apm/plugin/jdbc/SWStatementTest.java

@@ -13,8 +13,6 @@ import org.skywalking.apm.agent.core.boot.ServiceManager;
 import org.skywalking.apm.agent.core.context.TracerContext;
 import org.skywalking.apm.sniffer.mock.context.MockTracerContextListener;
 import org.skywalking.apm.sniffer.mock.context.SegmentAssert;
-import org.skywalking.apm.agent.core.context.trace.LogData;
-import org.skywalking.apm.agent.core.context.trace.Span;
 import org.skywalking.apm.agent.core.context.trace.TraceSegment;
 
 import java.net.MalformedURLException;

apm-sniffer/apm-sdk-plugin/jdbc-plugin/src/test/java/org/skywalking/apm/plugin/jdbc/SwPreparedStatementTest.java

@@ -16,8 +16,6 @@ import org.skywalking.apm.agent.core.boot.ServiceManager;
 import org.skywalking.apm.agent.core.context.TracerContext;
 import org.skywalking.apm.sniffer.mock.context.MockTracerContextListener;
 import org.skywalking.apm.sniffer.mock.context.SegmentAssert;
-import org.skywalking.apm.agent.core.context.trace.LogData;
-import org.skywalking.apm.agent.core.context.trace.Span;
 import org.skywalking.apm.agent.core.context.trace.TraceSegment;
 
 import java.io.InputStream;

apm-sniffer/apm-sdk-plugin/jedis-2.x-plugin/src/test/java/org/skywalking/apm/plugin/jedis/v2/JedisMethodInterceptorTest.java

@@ -16,10 +16,7 @@ import org.skywalking.apm.agent.core.plugin.interceptor.EnhancedClassInstanceCon
 import org.skywalking.apm.agent.core.plugin.interceptor.enhance.InstanceMethodInvokeContext;
 import org.skywalking.apm.sniffer.mock.context.MockTracerContextListener;
 import org.skywalking.apm.sniffer.mock.context.SegmentAssert;
-import org.skywalking.apm.sniffer.mock.trace.tags.BooleanTagReader;
 import org.skywalking.apm.sniffer.mock.trace.tags.StringTagReader;
-import org.skywalking.apm.agent.core.context.trace.LogData;
-import org.skywalking.apm.agent.core.context.trace.Span;
 import org.skywalking.apm.agent.core.context.trace.TraceSegment;
 import org.skywalking.apm.agent.core.context.tag.Tags;
 

apm-sniffer/apm-sdk-plugin/mongodb-3.x-plugin/src/test/java/org/skywalking/apm/plugin/mongodb/v3/MongoDBMethodInterceptorTest.java

@@ -23,8 +23,6 @@ import org.skywalking.apm.sniffer.mock.context.MockTracerContextListener;
 import org.skywalking.apm.sniffer.mock.context.SegmentAssert;
 import org.skywalking.apm.sniffer.mock.trace.SpanLogReader;
 import org.skywalking.apm.sniffer.mock.trace.tags.StringTagReader;
-import org.skywalking.apm.agent.core.context.trace.LogData;
-import org.skywalking.apm.agent.core.context.trace.Span;
 import org.skywalking.apm.agent.core.context.trace.TraceSegment;
 import org.skywalking.apm.agent.core.context.tag.Tags;
 

apm-sniffer/apm-sdk-plugin/mongodb-3.x-plugin/src/test/java/org/skywalking/apm/plugin/mongodb/v3/MongoDBWriteMethodInterceptorTest.java

@@ -24,8 +24,6 @@ import org.skywalking.apm.sniffer.mock.context.MockTracerContextListener;
 import org.skywalking.apm.sniffer.mock.context.SegmentAssert;
 import org.skywalking.apm.sniffer.mock.trace.SpanLogReader;
 import org.skywalking.apm.sniffer.mock.trace.tags.StringTagReader;
-import org.skywalking.apm.agent.core.context.trace.LogData;
-import org.skywalking.apm.agent.core.context.trace.Span;
 import org.skywalking.apm.agent.core.context.trace.TraceSegment;
 import org.skywalking.apm.agent.core.context.tag.Tags;
 

apm-sniffer/apm-sdk-plugin/motan-plugin/src/test/java/org/skywalking/apm/plugin/motan/MotanConsumerInterceptorTest.java

@@ -19,8 +19,6 @@ import org.skywalking.apm.sniffer.mock.context.MockTracerContextListener;
 import org.skywalking.apm.sniffer.mock.context.SegmentAssert;
 import org.skywalking.apm.sniffer.mock.trace.SpanLogReader;
 import org.skywalking.apm.sniffer.mock.trace.tags.StringTagReader;
-import org.skywalking.apm.agent.core.context.trace.LogData;
-import org.skywalking.apm.agent.core.context.trace.Span;
 import org.skywalking.apm.agent.core.context.trace.TraceSegment;
 import org.skywalking.apm.agent.core.context.tag.Tags;
 

apm-sniffer/apm-sdk-plugin/motan-plugin/src/test/java/org/skywalking/apm/plugin/motan/MotanProviderInterceptorTest.java

@@ -21,8 +21,6 @@ import org.skywalking.apm.sniffer.mock.context.MockTracerContextListener;
 import org.skywalking.apm.sniffer.mock.context.SegmentAssert;
 import org.skywalking.apm.sniffer.mock.trace.SpanLogReader;
 import org.skywalking.apm.sniffer.mock.trace.tags.StringTagReader;
-import org.skywalking.apm.agent.core.context.trace.LogData;
-import org.skywalking.apm.agent.core.context.trace.Span;
 import org.skywalking.apm.agent.core.context.trace.TraceSegment;
 import org.skywalking.apm.agent.core.context.trace.TraceSegmentRef;
 import org.skywalking.apm.agent.core.context.tag.Tags;

apm-sniffer/apm-sdk-plugin/okhttp-3.x-plugin/src/main/java/org/skywalking/apm/plugin/okhttp/v3/RealCallInterceptor.java

@@ -11,7 +11,6 @@ import org.skywalking.apm.agent.core.context.ContextCarrier;
 import org.skywalking.apm.agent.core.context.ContextManager;
 import org.skywalking.apm.agent.core.context.tag.Tags;
 import org.skywalking.apm.agent.core.context.trace.AbstractSpan;
-import org.skywalking.apm.agent.core.context.trace.Span;
 import org.skywalking.apm.agent.core.plugin.interceptor.EnhancedClassInstanceContext;
 import org.skywalking.apm.agent.core.plugin.interceptor.enhance.ConstructorInvokeContext;
 import org.skywalking.apm.agent.core.plugin.interceptor.enhance.InstanceConstructorInterceptor;

apm-sniffer/apm-sdk-plugin/okhttp-3.x-plugin/src/test/java/org/skywalking/apm/plugin/okhttp/v3/RealCallInterceptorTest.java

@@ -20,7 +20,6 @@ import org.skywalking.apm.sniffer.mock.context.SegmentAssert;
 import org.skywalking.apm.sniffer.mock.trace.SpanLogReader;
 import org.skywalking.apm.sniffer.mock.trace.tags.BooleanTagReader;
 import org.skywalking.apm.sniffer.mock.trace.tags.StringTagReader;
-import org.skywalking.apm.agent.core.context.trace.Span;
 import org.skywalking.apm.agent.core.context.trace.TraceSegment;
 import org.skywalking.apm.agent.core.context.tag.Tags;
 

apm-sniffer/apm-sdk-plugin/resin-3.x-plugin/src/test/java/org/skywalking/apm/plugin/resin/v3/ResinV3InterceptorTest.java

@@ -20,8 +20,6 @@ import org.skywalking.apm.sniffer.mock.context.SegmentAssert;
 import org.skywalking.apm.sniffer.mock.trace.SpanLogReader;
 import org.skywalking.apm.sniffer.mock.trace.tags.IntTagReader;
 import org.skywalking.apm.sniffer.mock.trace.tags.StringTagReader;
-import org.skywalking.apm.agent.core.context.trace.LogData;
-import org.skywalking.apm.agent.core.context.trace.Span;
 import org.skywalking.apm.agent.core.context.trace.TraceSegment;
 import org.skywalking.apm.agent.core.context.trace.TraceSegmentRef;
 import org.skywalking.apm.agent.core.context.tag.Tags;

apm-sniffer/apm-sdk-plugin/resin-4.x-plugin/src/test/java/org/skywalking/apm/plugin/resin/v4/ResinV4InterceptorTest.java

@@ -20,8 +20,6 @@ import org.skywalking.apm.sniffer.mock.context.SegmentAssert;
 import org.skywalking.apm.sniffer.mock.trace.SpanLogReader;
 import org.skywalking.apm.sniffer.mock.trace.tags.IntTagReader;
 import org.skywalking.apm.sniffer.mock.trace.tags.StringTagReader;
-import org.skywalking.apm.agent.core.context.trace.LogData;
-import org.skywalking.apm.agent.core.context.trace.Span;
 import org.skywalking.apm.agent.core.context.trace.TraceSegment;
 import org.skywalking.apm.agent.core.context.trace.TraceSegmentRef;
 import org.skywalking.apm.agent.core.context.tag.Tags;

apm-sniffer/apm-sdk-plugin/tomcat-7.x-8.x-plugin/src/test/java/org/skywalking/apm/plugin/tomcat78x/TomcatInterceptorTest.java

@@ -20,8 +20,6 @@ import org.skywalking.apm.sniffer.mock.context.SegmentAssert;
 import org.skywalking.apm.sniffer.mock.trace.SpanLogReader;
 import org.skywalking.apm.sniffer.mock.trace.tags.IntTagReader;
 import org.skywalking.apm.sniffer.mock.trace.tags.StringTagReader;
-import org.skywalking.apm.agent.core.context.trace.LogData;
-import org.skywalking.apm.agent.core.context.trace.Span;
 import org.skywalking.apm.agent.core.context.trace.TraceSegment;
 import org.skywalking.apm.agent.core.context.trace.TraceSegmentRef;
 import org.skywalking.apm.agent.core.context.tag.Tags;

apm-sniffer/apm-sniffer-mock/src/main/java/org/skywalking/apm/sniffer/mock/trace/SpanLogReader.java

@@ -2,8 +2,6 @@ package org.skywalking.apm.sniffer.mock.trace;
 
 import java.lang.reflect.Field;
 import java.util.List;
-import org.skywalking.apm.agent.core.context.trace.LogData;
-import org.skywalking.apm.agent.core.context.trace.Span;
 
 /**
  * @author wusheng

apm-sniffer/apm-sniffer-mock/src/main/java/org/skywalking/apm/sniffer/mock/trace/tags/BooleanTagReader.java

@@ -2,7 +2,6 @@ package org.skywalking.apm.sniffer.mock.trace.tags;
 
 import java.lang.reflect.Field;
 import java.util.List;
-import org.skywalking.apm.agent.core.context.trace.Span;
 import org.skywalking.apm.agent.core.context.tag.BooleanTag;
 import org.skywalking.apm.agent.core.context.tag.BooleanTagItem;
 

apm-sniffer/apm-sniffer-mock/src/main/java/org/skywalking/apm/sniffer/mock/trace/tags/IntTagReader.java

@@ -2,7 +2,6 @@ package org.skywalking.apm.sniffer.mock.trace.tags;
 
 import java.lang.reflect.Field;
 import java.util.List;
-import org.skywalking.apm.agent.core.context.trace.Span;
 import org.skywalking.apm.agent.core.context.tag.IntTag;
 import org.skywalking.apm.agent.core.context.tag.IntTagItem;
 

apm-sniffer/apm-sniffer-mock/src/main/java/org/skywalking/apm/sniffer/mock/trace/tags/StringTagReader.java

@@ -2,7 +2,6 @@ package org.skywalking.apm.sniffer.mock.trace.tags;
 
 import java.lang.reflect.Field;
 import java.util.List;
-import org.skywalking.apm.agent.core.context.trace.Span;
 import org.skywalking.apm.agent.core.context.tag.StringTag;
 import org.skywalking.apm.agent.core.context.tag.StringTagItem;
 

pom.xml

@@ -72,12 +72,6 @@
     </properties>
 
     <dependencies>
-        <dependency>
-            <groupId>com.google.code.gson</groupId>
-            <artifactId>gson</artifactId>
-            <version>2.8.0</version>
-        </dependency>
-
         <dependency>
             <groupId>junit</groupId>
             <artifactId>junit</artifactId>