Boorstrap Java lesson 1

Author: Yuri Shkuro

java/.gitignore

@@ -1 +1,4 @@
+.classpath
+.project
+.settings/
 target/

java/README.md

@@ -1,43 +1,33 @@
-# OpenTracing Tutorial - Go
+# OpenTracing Tutorial - Java
 
 ## Installing
 
 The tutorials are using CNCF Jaeger (https://github.com/jaegertracing/jaeger) as the tracing backend, 
 [see here](../README.md) how to install it in a Docker image.
 
-This repository uses [glide](https://github.com/Masterminds/glide) to manage dependencies (installed automatically below).
-
-When you clone the tutorials repository, it should be located in the right place under `$GOPATH`:
-
-```
-mkdir -p $GOPATH/src/github.com/yurishkuro/
-cd $GOPATH/src/github.com/yurishkuro/
-git clone https://github.com/yurishkuro/opentracing-tutorial.git opentracing-tutorial
-```
-
-After that, install the dependencies:
+This repository uses Maven to manage dependencies. To install all dependencies, run:
 
 ```
-cd $GOPATH/src/github.com/yurishkuro/opentracing-tutorial/go
-make install
+cd opentracing-tutorial/java
+mvn package
 ```
 
-The rest of the commands in the Go tutorials should be executed relative to this directory.
+All subsequent commands in the tutorials should be executed relative to this `java` directory.
 
 ## Lessons
 
-* [Lesson 01 - Hello World](lesson01)
+* [Lesson 01 - Hello World](./src/main/java/lesson01)
   * Instantiate a Tracer
   * Create a simple trace
   * Annotate the trace
-* [Lesson 02 - Context and Tracing Functions](lesson02)
+* [Lesson 02 - Context and Tracing Functions](./src/main/java/lesson02)
   * Trace individual functions
   * Combine multiple spans into a single trace
   * Propagate the in-process context
-* [Lesson 03 - Tracing RPC Requests](lesson03)
+* [Lesson 03 - Tracing RPC Requests](./src/main/java/lesson03)
   * Trace a transaction across more than one microservice
   * Pass the context between processes using `Inject` and `Extract`
   * Apply OpenTracing-recommended tags
-* [Lesson 04 - Baggage](lesson04)
+* [Lesson 04 - Baggage](./src/main/java/lesson04)
   * Understand distributed context propagation
   * Use baggage to pass data through the call graph

java/pom.xml

@@ -1,20 +1,34 @@
 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
   xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
-  <modelVersion>4.0.0</modelVersion>
-  <groupId>com.github.yurishkuro</groupId>
-  <artifactId>java-opentracing-tutorial</artifactId>
-  <packaging>jar</packaging>
-  <version>1.0-SNAPSHOT</version>
-  <name>java-opentracing-tutorial</name>
-  <url>http://maven.apache.org</url>
-  <properties>
-    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-  </properties>
-  <dependencies>
-    <dependency>
-      <groupId>com.uber.jaeger</groupId>
-      <artifactId>jaeger-core</artifactId>
-      <version>0.21.0</version>
-    </dependency>
-  </dependencies>
+    <modelVersion>4.0.0</modelVersion>
+    <groupId>com.github.yurishkuro</groupId>
+    <artifactId>java-opentracing-tutorial</artifactId>
+    <packaging>jar</packaging>
+    <version>1.0-SNAPSHOT</version>
+    <name>java-opentracing-tutorial</name>
+    <url>http://maven.apache.org</url>
+    <properties>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+    </properties>
+    <!--
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.codehaus.mojo</groupId>
+                <artifactId>exec-maven-plugin</artifactId>
+                <version>1.5</version>
+                <configuration>
+                    <mainClass>lesson01.solution.Hello</mainClass>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
+    -->
+    <dependencies>
+        <dependency>
+            <groupId>com.uber.jaeger</groupId>
+            <artifactId>jaeger-core</artifactId>
+            <version>0.21.0</version>
+        </dependency>
+    </dependencies>
 </project>

java/run.sh

@@ -0,0 +1,11 @@
+#!/bin/bash
+
+if [ "$1" == "" ]; then
+    echo "Usage: run.sh qualified-class-name [args]"
+    exit 1
+fi
+
+className=$1
+shift
+
+mvn exec:java -Dexec.mainClass="$className" -Dexec.args="$*" | grep -v -e '\[INFO\]' -e '\[WARNING\]' -e '\[ERROR\]'

java/src/main/java/lesson01/README.md

@@ -12,9 +12,18 @@ Learn how to:
 
 ### A simple Hello-World program
 
-Let's create a simple Go program `lesson01/hello.go` that takes an argument and prints "Hello, {arg}!". 
+Let's create a simple Java program `lesson01/Hello.java` that takes an argument and prints "Hello, {arg}!". 
+
+```java
+public class Hello {
+
+    public static void main(String[] args) {
+        System.out.println("Hello, World");
+    }
+
+}
+
 
-```go
 package main
 
 import (

java/src/main/java/lesson01/solution/Hello.java

@@ -0,0 +1,14 @@
+package lesson01.solution;
+
+public class Hello {
+
+    public static void main(String[] args) {
+        if (args.length != 1) {
+            throw new IllegalArgumentException("Expecting one argument");
+        }
+        String helloTo = args[0];
+        String helloStr = String.format("Hello, %s!", helloTo);
+        System.out.println(helloStr);
+    }
+
+}