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copied!<p>You can always patch the old class with <a href="http://asm.ow2.org/" rel="nofollow">ASM</a>. Generating a new class from the old bytecode by ignoring the clinit block should be easy.</p> <pre><code>import org.objectweb.asm.*; import org.objectweb.asm.commons.EmptyVisitor; import java.io.*; public class ClinitKiller { public static void main (String[] args) { final InputStream input = ClinitKiller.class.getResourceAsStream(Test.class.getName() + ".class"); try { final byte[] bytes = instrument(input); FileOutputStream out = new FileOutputStream("/tmp/Test.class"); out.write(bytes); out.close(); } catch (IOException e) { e.printStackTrace(); } } public static byte[] instrument(InputStream is) throws IOException { ClassReader reader = new ClassReader(is); ClassWriter writer = new ClassWriter(0); ClinitKillerClassAdapter classAdapter = new ClinitKillerClassAdapter(writer); reader.accept(classAdapter, 0); return writer.toByteArray(); } } class ClinitKillerClassAdapter extends ClassAdapter { public ClinitKillerClassAdapter(final ClassVisitor cv) { super(cv); } public MethodVisitor visitMethod(final int access, final String name, final String desc, final String signature, final String[] exceptions) { if (name.equals("<clinit>")) { return new EmptyVisitor(); } return cv.visitMethod(access, name, desc, signature, exceptions); } } </code></pre> <p>Here is the before and after for the following class:</p> <pre><code>public class Test { private static final String value; static { System.out.println("Test static"); value = "test value"; } public static void main(String[] args) { System.out.println(value); } } </code></pre> <p>Before: </p> <pre><code>javap -c Test Compiled from "Test.java" public class Test extends java.lang.Object{ public Test(); Code: 0: aload_0 1: invokespecial #1; //Method java/lang/Object."<init>":()V 4: return public static void main(java.lang.String[]); Code: 0: getstatic #2; //Field java/lang/System.out:Ljava/io/PrintStream; 3: getstatic #3; //Field value:Ljava/lang/String; 6: invokevirtual #4; //Method java/io/PrintStream.println:(Ljava/lang/String;)V 9: return static {}; Code: 0: getstatic #2; //Field java/lang/System.out:Ljava/io/PrintStream; 3: ldc #5; //String Test static 5: invokevirtual #4; //Method java/io/PrintStream.println:(Ljava/lang/String;)V 8: ldc #6; //String test value 10: putstatic #3; //Field value:Ljava/lang/String; 13: return } </code></pre> <p>Output:<br/> Test static<br/> test value<br/></p> <p>After:</p> <pre><code>javap -c Test Compiled from "Test.java" public class Test extends java.lang.Object{ public Test(); Code: 0: aload_0 1: invokespecial #11; //Method java/lang/Object."<init>":()V 4: return public static void main(java.lang.String[]); Code: 0: getstatic #21; //Field java/lang/System.out:Ljava/io/PrintStream; 3: getstatic #23; //Field value:Ljava/lang/String; 6: invokevirtual #29; //Method java/io/PrintStream.println:(Ljava/lang/String;)V 9: return } </code></pre> <p>Output:<br/> null</p>

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