Give a sample code of the first Mock trace.

skywalking-sniffer/skywalking-sniffer-mock/src/main/java/com/a/eye/skywalking/sniffer/mock/trace/TraceSegmentBuilder.java

+package com.a.eye.skywalking.sniffer.mock.trace;
+
+import com.a.eye.skywalking.trace.TraceSegment;
+
+/**
+ * Created by wusheng on 2017/2/20.
+ */
+public interface TraceSegmentBuilder {
+    TraceSegment build();
+}

skywalking-sniffer/skywalking-sniffer-mock/src/main/java/com/a/eye/skywalking/sniffer/mock/trace/TraceSegmentBuilderFactory.java

+package com.a.eye.skywalking.sniffer.mock.trace;
+
+import com.a.eye.skywalking.sniffer.mock.trace.builders.SingleTomcat200TraceBuilder;
+import com.a.eye.skywalking.trace.TraceSegment;
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * The <code>TraceSegmentBuilderFactory</code> contains all {@link TraceSegmentBuilder} implementations.
+ * All the implementations can build a true {@link TraceSegment} object, and contain all necessary spans, with all tags/events, all refs.
+ *
+ * Created by wusheng on 2017/2/20.
+ */
+public enum TraceSegmentBuilderFactory {
+    INSTANCE;
+
+    private Map<String, TraceSegmentBuilder> allBuilders;
+
+    TraceSegmentBuilderFactory(){
+        allBuilders = new HashMap<String, TraceSegmentBuilder>();
+        initialize();
+    }
+
+    public TraceSegment singleTomcat200Trace(){
+        return allBuilders.get(SingleTomcat200TraceBuilder.INSTANCE).build();
+    }
+
+    private void initialize(){
+        initBuilder(SingleTomcat200TraceBuilder.INSTANCE);
+    }
+
+    private void initBuilder(TraceSegmentBuilder builder){
+        allBuilders.put(builder.toString(), builder);
+    }
+}

skywalking-sniffer/skywalking-sniffer-mock/src/main/java/com/a/eye/skywalking/sniffer/mock/trace/builders/SingleTomcat200TraceBuilder.java

+package com.a.eye.skywalking.sniffer.mock.trace.builders;
+
+import com.a.eye.skywalking.api.context.ContextManager;
+import com.a.eye.skywalking.sniffer.mock.trace.TraceSegmentBuilder;
+import com.a.eye.skywalking.trace.Span;
+import com.a.eye.skywalking.trace.TraceSegment;
+import com.a.eye.skywalking.trace.tag.Tags;
+
+/**
+ * A Trace contains only one span, which represent a tomcat server side span.
+ *
+ * Created by wusheng on 2017/2/20.
+ */
+public enum SingleTomcat200TraceBuilder implements TraceSegmentBuilder {
+    INSTANCE;
+
+    @Override public TraceSegment build() {
+        Span webSpan = ContextManager.INSTANCE.createSpan("/web/serviceA");
+        {
+            Tags.COMPONENT.set(webSpan, "tomcat");
+            Tags.URL.set(webSpan, "http://10.21.9.35/web/serviceA");
+            Tags.SPAN_KIND.set(webSpan, Tags.SPAN_KIND_SERVER);
+            Tags.STATUS_CODE.set(webSpan, 200);
+        }
+        return null;
+    }
+}