HotSwap support

git-svn-id: http://anonsvn.jboss.org/repos/javassist/trunk@184 30ef5769-5b8d-40dd-aea6-55b5d6557bb3

Readme.html

@@ -240,6 +240,33 @@ <h3>7. sample/evolve/*.java</h3>
    on the local host.
 (Or, see <a href="sample/evolve/start.html">sample/evolve/start.html</a>.)
 
+<h3>8. sample/hotswap/*.java</h3>
+
+<p>This shows dynamic class reloading by the JPDA.
+To run, first type the following commands:
+
+<ul><pre>
+% cd sample/hotswap
+% javac *.java
+% cd logging
+% javac *.java
+% cd ..
+</pre></ul>
+
+<p>If your Java is 1.4, then type:
+
+<ul><pre>
+% java -Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=n,address=8000 Test
+</pre></ul>
+
+<p>If you are using Java 5, then type:
+
+<ul><pre>
+% java -agentlib:jdwp=transport=dt_socket,server=y,suspend=n,address=8000 Test
+</pre></ul>
+
+<p>Note that the class path must include <code>JAVA_HOME/lib/tools.jar</code>.
+
 <h2>Hints</h2>
 
 <p>To know the version number, type this command:
@@ -258,6 +285,8 @@ <h2>Changes</h2>
 <p>- version 3.1
 
 <ul>
+  <li>javassist.tool.HotSwapper was added.
+  <li>javassist.Dump was moved to javassist.tool.Dump.
 </ul>
 
 <p>- version 3.0 in January 18, 2005

build.xml

@@ -6,7 +6,7 @@
 
 <project name="javassist" default="jar" basedir=".">
 
-  <property name="dist-version" value="javassist-3.0"/>
+  <property name="dist-version" value="javassist-3.1"/>
 
   <property environment="env"/>
   <property name="target.jar" value="javassist.jar"/>
@@ -51,15 +51,33 @@
            debug="on"
            deprecation="on"
            optimize="off"
-           includes="sample/**">
+           includes="sample/**"
+           excludes="sample/hotswap/**">
+            <classpath refid="classpath"/>
+    </javac>
+    <javac srcdir="${basedir}/sample/hotswap"
+           destdir="${build.classes.dir}"
+           debug="on"
+           deprecation="on"
+           optimize="off"
+           includes="*">
+            <classpath refid="classpath"/>
+    </javac>
+    <mkdir dir="${build.classes.dir}/logging"/>
+    <javac srcdir="${basedir}/sample/hotswap/logging"
+           destdir="${build.classes.dir}/logging"
+           debug="on"
+           deprecation="on"
+           optimize="off"
+           includes="*">
             <classpath refid="classpath"/>
     </javac>
     <copy file="sample/vector/Test.j"
           todir="${build.classes.dir}/sample/vector"/>
     <copy todir="${build.classes.dir}/sample/evolve">
       <fileset dir="sample/evolve"/>
     </copy>
-    <echo>To run the sample programs, change the current directory 
+    <echo>To run the sample programs without ant, change the current directory 
 to ${build.classes.dir}.</echo>
   </target>
 
@@ -175,4 +193,21 @@ Copyright (C) 1999-2005 Shigeru Chiba. All Rights Reserved.</i>]]></bottom>
     </java>
   </target>
 
+  <!-- for JDK 1.4 -->
+  <target name = "sample-hotswap" depends="sample">
+    <echo>** JAVA_HOME/lib/tools.jar must be included in CLASS_PATH</echo>
+    <java fork="true" dir="${run.dir}" classname="Test">
+      <jvmarg line="-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=n,address=8000" />
+      <classpath refid="classpath"/>
+    </java>
+  </target>
+
+  <!-- for Java 5 -->
+  <target name = "sample-hotswap5" depends="sample">
+    <echo>** JAVA_HOME/lib/tools.jar must be included in CLASS_PATH</echo>
+    <java fork="true" dir="${run.dir}" classname="Test">
+      <jvmarg line="-agentlib:jdwp=transport=dt_socket,server=y,suspend=n,address=8000" />
+      <classpath refid="classpath"/>
+    </java>
+  </target>
 </project>

sample/hotswap/HelloWorld.java

@@ -0,0 +1,5 @@
+public class HelloWorld {
+    public void print() {
+        System.out.println("hello world");
+    }
+}

sample/hotswap/Test.java

@@ -0,0 +1,25 @@
+import java.io.*;
+import javassist.tool.HotSwapper;
+
+public class Test {
+    public static void main(String[] args) throws Exception {
+        HotSwapper hs = new HotSwapper(8000);
+        new HelloWorld().print();
+
+        File newfile = new File("logging/HelloWorld.class");
+        byte[] bytes = new byte[(int)newfile.length()];
+        new FileInputStream(newfile).read(bytes);
+        System.out.println("** reload a logging version");
+
+        hs.reload("HelloWorld", bytes);
+        new HelloWorld().print();
+
+        newfile = new File("HelloWorld.class");
+        bytes = new byte[(int)newfile.length()];
+        new FileInputStream(newfile).read(bytes);
+        System.out.println("** reload the original version");
+
+        hs.reload("HelloWorld", bytes);
+        new HelloWorld().print();
+    }
+}

sample/hotswap/logging/HelloWorld.java

@@ -0,0 +1,6 @@
+public class HelloWorld {
+    public void print() {
+        System.out.println("** HelloWorld.print()");
+        System.out.println("hello world");
+    }
+}

src/main/javassist/Dump.java → src/main/javassist/tool/Dump.java

@@ -13,7 +13,7 @@
  * License.
  */
 
-package javassist;
+package javassist.tool;
 
 import java.io.*;
 import javassist.bytecode.ClassFile;
@@ -25,7 +25,7 @@
  * the class file is broken.
  *
  * <p>For example,
- * <ul><pre>% java javassist.Dump foo.class</pre></ul>
+ * <ul><pre>% java javassist.tool.Dump foo.class</pre></ul>
  *
  * <p>prints the contents of the constant pool and the list of methods
  * and fields.