[#106] Converted UUID to Long

- Changed Random instantiation to a shared Random
- Changed the name of the converter
- Changed generator into random
- Span id is now non-nullable.
    - it gets generated in the http filter if it's not there
    - it's generated in the spring-integration channels if it wasn't set

spring-cloud-sleuth-samples/spring-cloud-sleuth-sample-zipkin/src/main/java/sample/SampleBackground.java

@@ -16,15 +16,14 @@
 
 package sample;
 
-import java.util.Random;
-
 import lombok.SneakyThrows;
-
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.cloud.sleuth.TraceManager;
 import org.springframework.scheduling.annotation.Async;
 import org.springframework.stereotype.Component;
 
+import java.util.Random;
+
 /**
  * @author Spencer Gibb
  */
@@ -33,11 +32,12 @@ public class SampleBackground {
 
 	@Autowired
 	private TraceManager traceManager;
+	@Autowired
+	private Random random;
 
 	@SneakyThrows
 	@Async
 	public void background() {
-		final Random random = new Random();
 		int millis = random.nextInt(1000);
 		Thread.sleep(millis);
 		this.traceManager.addAnnotation("background-sleep-millis", String.valueOf(millis));

spring-cloud-sleuth-samples/spring-cloud-sleuth-sample-zipkin/src/main/java/sample/SampleController.java

@@ -16,9 +16,8 @@
 
 package sample;
 
-import java.util.Random;
-import java.util.concurrent.Callable;
-
+import lombok.SneakyThrows;
+import lombok.extern.slf4j.Slf4j;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.context.embedded.EmbeddedServletContainerInitializedEvent;
 import org.springframework.cloud.sleuth.Span;
@@ -31,8 +30,8 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.client.RestTemplate;
 
-import lombok.SneakyThrows;
-import lombok.extern.slf4j.Slf4j;
+import java.util.Random;
+import java.util.concurrent.Callable;
 
 /**
  * @author Spencer Gibb
@@ -49,12 +48,13 @@ ApplicationListener<EmbeddedServletContainerInitializedEvent> {
 	private TraceAccessor accessor;
 	@Autowired
 	private SampleBackground controller;
+	@Autowired
+	private Random random;
 	private int port;
 
 	@SneakyThrows
 	@RequestMapping("/")
 	public String hi() {
-		final Random random = new Random();
 		Thread.sleep(random.nextInt(1000));
 
 		String s = this.restTemplate.getForObject("http://localhost:" + this.port
@@ -67,7 +67,6 @@ ApplicationListener<EmbeddedServletContainerInitializedEvent> {
 		return new Callable<String>() {
 			@Override
 			public String call() throws Exception {
-				final Random random = new Random();
 				int millis = random.nextInt(1000);
 				Thread.sleep(millis);
 				SampleController.this.traceManager.addAnnotation("callable-sleep-millis", String.valueOf(millis));
@@ -86,7 +85,6 @@ ApplicationListener<EmbeddedServletContainerInitializedEvent> {
 	@SneakyThrows
 	@RequestMapping("/hi2")
 	public String hi2() {
-		final Random random = new Random();
 		int millis = random.nextInt(1000);
 		Thread.sleep(millis);
 		this.traceManager.addAnnotation("random-sleep-millis", String.valueOf(millis));
@@ -98,7 +96,6 @@ ApplicationListener<EmbeddedServletContainerInitializedEvent> {
 	public String traced() {
 		Trace trace = this.traceManager.startSpan("customTraceEndpoint",
 				new AlwaysSampler(), null);
-		final Random random = new Random();
 		int millis = random.nextInt(1000);
 		log.info("Sleeping for {} millis", millis);
 		Thread.sleep(millis);
@@ -113,7 +110,6 @@ ApplicationListener<EmbeddedServletContainerInitializedEvent> {
 	@SneakyThrows
 	@RequestMapping("/start")
 	public String start() {
-		final Random random = new Random();
 		int millis = random.nextInt(1000);
 		log.info("Sleeping for {} millis", millis);
 		Thread.sleep(millis);

spring-cloud-sleuth-samples/spring-cloud-sleuth-sample-zipkin/src/test/java/integration/ZipkinTests.java

@@ -31,10 +31,11 @@ import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.test.context.TestPropertySource;
 import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
-import org.springframework.util.JdkIdGenerator;
 import sample.SampleZipkinApplication;
 import tools.AbstractIntegrationTest;
 
+import java.util.Random;
+
 @RunWith(SpringJUnit4ClassRunner.class)
 @SpringApplicationConfiguration(classes = { WaitUntilZipkinIsUpConfig.class,
 		SampleZipkinApplication.class })
@@ -53,9 +54,8 @@ public class ZipkinTests extends AbstractIntegrationTest {
 	}
 
 	@Test
-	@SneakyThrows
 	public void should_propagate_spans_to_zipkin() {
-		String traceId = new JdkIdGenerator().generateId().toString();
+		long traceId = new Random().nextLong();
 
 		await().until(httpMessageWithTraceIdInHeadersIsSuccessfullySent(
 				sampleAppUrl + "/hi2", traceId));