Improve Java examples

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MOS_MIGRATED_REVID=86787893

4 files changed, 73 insertions, 0 deletions

diff --git a/base_workspace/examples/java-skylark/src/main/java/com/example/myproject/BUILD b/base_workspace/examples/java-skylark/src/main/java/com/example/myproject/BUILD
new file mode 100644
index 0000000000..ed69d7f2b3
--- /dev/null
+++ b/base_workspace/examples/java-skylark/src/main/java/com/example/myproject/BUILD
@@ -0,0 +1,21 @@
+load("tools/build_rules/java_rules_skylark", "java_library", "java_binary", "java_test")
+
+package(default_visibility = ["//visibility:public"])
+
+java_binary(
+    name = "hello-world",
+    srcs = ["Greeter.java"],
+    main_class = "com.example.myproject.Greeter",
+)
+
+java_binary(
+    name = "hello-data",
+    main_class = "com.example.myproject.Greeter",
+    deps = [":hello-lib"],
+)
+
+java_library(
+    name = "hello-lib",
+    srcs = ["Greeter.java"],
+    data = ["//examples/java-skylark/src/main/resources:greeting"],
+)
diff --git a/base_workspace/examples/java-skylark/src/main/java/com/example/myproject/Greeter.java b/base_workspace/examples/java-skylark/src/main/java/com/example/myproject/Greeter.java
new file mode 100644
index 0000000000..b4d8516dc9
--- /dev/null
+++ b/base_workspace/examples/java-skylark/src/main/java/com/example/myproject/Greeter.java
@@ -0,0 +1,45 @@
+package com.example.myproject;
+
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.InputStream;
+import java.io.PrintStream;
+import java.util.Scanner;
+
+/**
+ * Prints a greeting which can be customized by building with data and/or passing in command-
+ * line arguments.
+ */
+public class Greeter {
+  static PrintStream out = System.out;
+
+  public static String getRunfiles() {
+    String path = System.getenv("JAVA_RUNFILES");
+    if (path == null) {
+      path = System.getenv("TEST_SRCDIR");
+    }
+    return path;
+  }
+
+  public static String convertStreamToString(InputStream is) throws Exception {
+    Scanner s = new Scanner(is).useDelimiter("\n");
+    return s.hasNext() ? s.next() : "";
+  }
+
+  public void hello(String obj) throws Exception {
+    String greeting = "Hello";
+    try {
+      String greetFile = getRunfiles() + "/examples/java-skylark/src/main/resources/greeting.txt";
+      greeting = convertStreamToString(new FileInputStream(greetFile));
+    } catch (FileNotFoundException e) {
+      // use default.
+    }
+    out.println(greeting + " " + obj);
+  }
+
+  public static void main(String... args) throws Exception {
+    Greeter g = new Greeter();
+    String obj = args.length > 0 ? args[0] : "world";
+    g.hello(obj);
+  }
+};
diff --git a/base_workspace/examples/java-skylark/src/main/resources/BUILD b/base_workspace/examples/java-skylark/src/main/resources/BUILD
new file mode 100644
index 0000000000..8347a3555a
--- /dev/null
+++ b/base_workspace/examples/java-skylark/src/main/resources/BUILD
@@ -0,0 +1,6 @@
+package(default_visibility = ["//visibility:public"])
+
+filegroup(
+    name = "greeting",
+    srcs = ["greeting.txt"],
+)
diff --git a/base_workspace/examples/java-skylark/src/main/resources/greeting.txt b/base_workspace/examples/java-skylark/src/main/resources/greeting.txt
new file mode 100644
index 0000000000..17654db5a1
--- /dev/null
+++ b/base_workspace/examples/java-skylark/src/main/resources/greeting.txt
@@ -0,0 +1 @@
+Heyo