add `final` keyword to some class

sharding-opentracing/src/main/java/io/shardingjdbc/opentracing/config/ConfigurationLoader.java

@@ -27,7 +27,7 @@ import lombok.Getter;
  * @author gaohongtao
  * @author wangkai
  */
-public class ConfigurationLoader {
+public final class ConfigurationLoader {
     
     private static final ConfigurationParser[] PARSERS = new ConfigurationParser[]{new OpentracingConfigurationParser()};
     

sharding-opentracing/src/main/java/io/shardingjdbc/opentracing/config/OpentracingConfigurationParser.java

@@ -25,7 +25,7 @@ import com.google.common.base.Optional;
  * @author gaohongtao
  * @author wangkai
  */
-public class OpentracingConfigurationParser implements ConfigurationParser {
+public final class OpentracingConfigurationParser implements ConfigurationParser {
     
     private static final String PREFIX = "shardingjdbc.opentracing";
     

sharding-opentracing/src/test/java/io/shardingjdbc/opentracing/AllTests.java

@@ -22,7 +22,8 @@ import org.junit.runner.RunWith;
 import org.junit.runners.Suite;
 
 @RunWith(Suite.class)
-@Suite.SuiteClasses({ConfigurationLoaderTest.class,
+@Suite.SuiteClasses({
+        ConfigurationLoaderTest.class,
         ExecuteEventListenerTest.class,
         ShardingJDBCTracerTest.class
 })

sharding-opentracing/src/test/java/io/shardingjdbc/opentracing/ExecuteEventListenerTest.java

@@ -41,7 +41,7 @@ import static org.junit.Assert.assertThat;
 import static org.powermock.api.mockito.PowerMockito.mock;
 import static org.powermock.api.mockito.PowerMockito.when;
 
-public class ExecuteEventListenerTest {
+public final class ExecuteEventListenerTest {
     
     private static final MockTracer TRACER = new MockTracer(new ThreadLocalActiveSpanSource(),
             MockTracer.Propagator.TEXT_MAP);

sharding-opentracing/src/test/java/io/shardingjdbc/opentracing/ShardingJDBCTracerTest.java

@@ -40,7 +40,7 @@ import static org.powermock.api.mockito.PowerMockito.when;
 
 @RunWith(PowerMockRunner.class)
 @PrepareForTest(OpentracingConfigurationParser.class)
-public class ShardingJDBCTracerTest {
+public final class ShardingJDBCTracerTest {
     
     @Before
     public void setUp() throws Exception {

sharding-opentracing/src/test/java/io/shardingjdbc/opentracing/config/ConfigurationLoaderTest.java

@@ -30,7 +30,7 @@ import static org.powermock.api.mockito.PowerMockito.when;
 
 @RunWith(PowerMockRunner.class)
 @PrepareForTest(OpentracingConfigurationParser.class)
-public class ConfigurationLoaderTest {
+public final class ConfigurationLoaderTest {
     
     @Before
     public void setUp() {

sharding-opentracing/src/test/java/io/shardingjdbc/opentracing/fixture/FooTracer.java

@@ -23,7 +23,7 @@ import io.opentracing.SpanContext;
 import io.opentracing.Tracer;
 import io.opentracing.propagation.Format;
 
-public class FooTracer implements Tracer {
+public final class FooTracer implements Tracer {
     
     @Override
     public SpanBuilder buildSpan(final String s) {
@@ -31,7 +31,8 @@ public class FooTracer implements Tracer {
     }
     
     @Override
-    public <C> void inject(final SpanContext spanContext, final Format<C> format, final C c) {}
+    public <C> void inject(final SpanContext spanContext, final Format<C> format, final C c) {
+    }
     
     @Override
     public <C> SpanContext extract(final Format<C> format, final C c) {