asm でバイトコード生成
とりあえずテスト
String className = "kuzha.code.jvm.JvmCodeBlock"; ClassWriter cv = new ClassWriter(ClassWriter.COMPUTE_MAXS); MethodVisitor mv; cv.visit(V1_5, ACC_PUBLIC, className.replace('.', '/'), null, "kuzha/code/CodeBlock", new String[0]); mv = cv.visitMethod(ACC_PUBLIC, "<init>", "()V", null, null); mv.visitCode(); mv.visitVarInsn(ALOAD, 0); mv.visitMethodInsn(INVOKESPECIAL, "kuzha/code/CodeBlock", "<init>", "()V"); mv.visitInsn(RETURN); mv.visitMaxs(0, 0); mv.visitEnd(); mv = cv.visitMethod(ACC_PUBLIC, "exec", "(Lkuzha/KuzhaObject;Lkuzha/object/KuSlotTable;)Lkuzha/KuzhaObject;", null, null); mv.visitCode(); mv.visitFieldInsn(GETSTATIC, "java/lang/System", "out", "Ljava/io/PrintStream;"); mv.visitLdcInsn("Hello Kuzha!"); mv.visitMethodInsn(INVOKEVIRTUAL, "java/io/PrintStream", "println", "(Ljava/lang/String;)V"); mv.visitInsn(ACONST_NULL); mv.visitInsn(ARETURN); mv.visitMaxs(0, 0); mv.visitEnd(); cv.visitEnd(); byte[] data = cv.toByteArray();
うむ。お手軽お手軽。