Merge pull request #237 from tomasp8/better-build

Improve build script: fork the same JRE, show target descriptions

h2/src/installer/checkstyle.xml

@@ -39,7 +39,7 @@
         <module name="ParenPad"/>
         <module name="WhitespaceAfter"/>
         <module name="WhitespaceAround">
-            <property name="tokens" value="ASSIGN,BAND,BAND_ASSIGN,BOR,BOR_ASSIGN,BSR,BSR_ASSIGN,BXOR,BXOR_ASSIGN,DIV_ASSIGN,EQUAL,GE,GT,LAND,LE,LITERAL_ASSERT,LITERAL_CATCH,LITERAL_DO,LITERAL_ELSE,LITERAL_FINALLY,LITERAL_FOR,LITERAL_IF,LITERAL_RETURN,LITERAL_SYNCHRONIZED,LITERAL_TRY,LITERAL_WHILE,LOR,LT,MINUS,MINUS_ASSIGN,MOD,MOD_ASSIGN,NOT_EQUAL,PLUS_ASSIGN,SL,SLIST,SL_ASSIGN,SR,SR_ASSIGN,STAR,STAR_ASSIGN,LITERAL_ASSERT,TYPE_EXTENSION_AND,WILDCARD_TYPE"/>
+            <property name="tokens" value="ASSIGN,BAND,BAND_ASSIGN,BOR,BOR_ASSIGN,BSR,BSR_ASSIGN,BXOR,BXOR_ASSIGN,DIV_ASSIGN,EQUAL,GE,GT,LAND,LE,LITERAL_ASSERT,LITERAL_CATCH,LITERAL_DO,LITERAL_ELSE,LITERAL_FINALLY,LITERAL_FOR,LITERAL_IF,LITERAL_RETURN,LITERAL_SYNCHRONIZED,LITERAL_TRY,LITERAL_WHILE,LOR,LT,MINUS,MINUS_ASSIGN,MOD,MOD_ASSIGN,NOT_EQUAL,PLUS_ASSIGN,SL,SLIST,SL_ASSIGN,SR,SR_ASSIGN,STAR,STAR_ASSIGN,LITERAL_ASSERT,TYPE_EXTENSION_AND"/>
         </module>
         <module name="ModifierOrder"/>
         <module name="RedundantModifier"/>

h2/src/tools/org/h2/build/BuildBase.java

@@ -18,6 +18,11 @@ import java.io.InputStreamReader;
 import java.io.OutputStream;
 import java.io.PrintStream;
 import java.io.RandomAccessFile;
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
 import java.lang.reflect.Field;
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
@@ -36,6 +41,7 @@ import java.util.zip.Deflater;
 import java.util.zip.ZipEntry;
 import java.util.zip.ZipOutputStream;
 
+
 /**
  * This class is a complete pure Java build tool. It allows to build this
  * project without any external dependencies except a JDK.
@@ -44,6 +50,16 @@ import java.util.zip.ZipOutputStream;
  */
 public class BuildBase {
 
+    /**
+     * Stores descriptions for methods which can be invoked as build targets.
+     */
+    @Retention(RetentionPolicy.RUNTIME)
+    @Target(ElementType.METHOD)
+    @Documented
+    public static @interface Description {
+      String summary() default "";
+    }
+
     /**
      * A list of strings.
      */
@@ -158,6 +174,18 @@ public class BuildBase {
      */
     protected boolean quiet;
 
+    /**
+     * The full path to the executable of the current JRE.
+     */
+    protected String javaExecutable = System.getProperty("java.home") +
+            File.separator + "bin" + File.separator + "java";
+
+    /**
+     * The full path to the tools jar of the current JDK.
+     */
+    protected String javaToolsJar = System.getProperty("java.home") + File.separator + ".." +
+            File.separator + "lib" + File.separator + "tools.jar";
+
     /**
      * This method should be called by the main method.
      *
@@ -283,11 +311,17 @@ public class BuildBase {
             }
         });
         sysOut.println("Targets:");
+        String description;
         for (Method m : methods) {
             int mod = m.getModifiers();
             if (!Modifier.isStatic(mod) && Modifier.isPublic(mod)
                     && m.getParameterTypes().length == 0) {
-                sysOut.println(m.getName());
+                if (m.isAnnotationPresent(Description.class)) {
+                    description = String.format("%1$-20s %2$s", m.getName(), m.getAnnotation(Description.class).summary());
+                } else {
+                    description = m.getName();
+                }
+                sysOut.println(description);
             }
         }
         sysOut.println();
@@ -320,6 +354,16 @@ public class BuildBase {
         return exec(script, args);
     }
 
+    /**
+     * Execute java in a separate process, but using the java executable of the current JRE.
+     *
+     * @param args the command line parameters for the java command
+     * @return the exit value
+     */
+    protected int execJava(StringList args) {
+        return exec(javaExecutable, args);
+    }
+
     /**
      * Execute a program in a separate process.
      *