Java Implementation类代码示例

import net.bytebuddy.implementation.Implementation; //导入依赖的package包/类
@Override
public final void check() throws Exception {
    Implementation.Context implementationContext = EasyMock.createMock(
        Implementation.Context.class
    );
    
    final MethodVisitorRecorder patternMvr = new MethodVisitorRecorder();
    final MethodVisitorRecorder actualMvr = new MethodVisitorRecorder();
    
    pattern.accept(patternMvr);
    System.out.println("Expectation:");
    patternMvr.trace();
    
    sm.apply(actualMvr, implementationContext);
    System.out.println("Reality:");
    actualMvr.trace();
    
    assertThat(actualMvr).isEqualTo(patternMvr);
}
 

import net.bytebuddy.implementation.Implementation; //导入依赖的package包/类
/**
 * Creates the AgentBuilder that will redefine the System class.
 * @param inst instrumentation instance.
 * @return an agent builder.
 */
private static AgentBuilder createAgentBuilder(Instrumentation inst) {

    // Find me a class called "java.lang.System"
    final ElementMatcher.Junction<NamedElement> systemType = ElementMatchers.named("java.lang.System");

    // And then find a method called setSecurityManager and tell MySystemInterceptor to
    // intercept it (the method binding is smart enough to take it from there)
    final AgentBuilder.Transformer transformer =
            (b, typeDescription) -> b.method(ElementMatchers.named("setSecurityManager"))
                    .intercept(MethodDelegation.to(MySystemInterceptor.class));

    // Disable a bunch of stuff and turn on redefine as the only option
    final ByteBuddy byteBuddy = new ByteBuddy().with(Implementation.Context.Disabled.Factory.INSTANCE);
    final AgentBuilder agentBuilder = new AgentBuilder.Default()
            .withByteBuddy(byteBuddy)
            .withInitializationStrategy(AgentBuilder.InitializationStrategy.NoOp.INSTANCE)
            .withRedefinitionStrategy(AgentBuilder.RedefinitionStrategy.REDEFINITION)
            .withTypeStrategy(AgentBuilder.TypeStrategy.Default.REDEFINE)
            .type(systemType)
            .transform(transformer);

    return agentBuilder;
}
 

import net.bytebuddy.implementation.Implementation; //导入依赖的package包/类
public Size apply(MethodVisitor methodVisitor, Implementation.Context implementationContext) {
  switch (variableIndex) {
    case 0:
      methodVisitor.visitInsn(storeOpcode + storeOpcodeShortcutOffset);
      break;
    case 1:
      methodVisitor.visitInsn(storeOpcode + storeOpcodeShortcutOffset + 1);
      break;
    case 2:
      methodVisitor.visitInsn(storeOpcode + storeOpcodeShortcutOffset + 2);
      break;
    case 3:
      methodVisitor.visitInsn(storeOpcode + storeOpcodeShortcutOffset + 3);
      break;
    default:
      methodVisitor.visitVarInsn(storeOpcode, variableIndex);
      break;
  }
  return size;
}
 

import net.bytebuddy.implementation.Implementation; //导入依赖的package包/类
public Size apply(MethodVisitor methodVisitor, Implementation.Context implementationContext,
    MethodDescription instrumentedMethod) {

  checkMethodSignature(instrumentedMethod);

  try {
    StackManipulation stack = buildStack();
    StackManipulation.Size finalStackSize = stack.apply(methodVisitor, implementationContext);

    return new Size(finalStackSize.getMaximalSize(),
        instrumentedMethod.getStackSize() + 2); // 2 stack slots for a single local variable

  } catch (NoSuchMethodException | NoSuchFieldException e) {
    throw new RuntimeException(e);
  }
}
 

import net.bytebuddy.implementation.Implementation; //导入依赖的package包/类
@Override
public Size apply(MethodVisitor methodVisitor, Implementation.Context implementationContext,
                MethodDescription instrumentedMethod) {
    switch (returnType) {
        case REFERENCE:
            return new Size(MethodReturn.REFERENCE.apply(methodVisitor, implementationContext).getMaximalSize(),
                            instrumentedMethod.getStackSize());
        case VOID:
            return new Size(MethodReturn.VOID.apply(methodVisitor, implementationContext).getMaximalSize(),
                            instrumentedMethod.getStackSize());
        case INT:
            return new Size(MethodReturn.INTEGER.apply(methodVisitor, implementationContext).getMaximalSize(),
                            instrumentedMethod.getStackSize());
        default:
            throw new IllegalStateException("Illegal opType");
    }

}
 

import net.bytebuddy.implementation.Implementation; //导入依赖的package包/类
@Override
public Size apply(MethodVisitor methodVisitor, Implementation.Context implementationContext,
                MethodDescription instrumentedMethod) {
    int numArgs = instrumentedMethod.getParameters().asTypeList().getStackSize();
    /**
     * Load the desired id
     * relative to the method arguments.
     * The idea here would be to load references
     * to declared variables
     */
    //references start with zero if its an instance or zero if its static
    //think of it like an implicit self in python without actually being defined
    int start = instrumentedMethod.isStatic() ? 1 : 0;
    StackManipulation arg0 = MethodVariableAccess.REFERENCE
                    .loadOffset(numArgs + start + OpCodeUtil.getAloadInstructionForReference(refId));
    StackManipulation.Size size = arg0.apply(methodVisitor, implementationContext);
    return new Size(size.getMaximalSize(), instrumentedMethod.getStackSize());
}
 

import net.bytebuddy.implementation.Implementation; //导入依赖的package包/类
@Test
public void testRetrieveFromArray() throws Exception {
    DynamicType.Unloaded<RetrieveFromArray> arr = new ByteBuddy().subclass(RetrieveFromArray.class)
                    .method(ElementMatchers.isDeclaredBy(RetrieveFromArray.class))
                    .intercept(new Implementation.Compound(new LoadReferenceParamImplementation(1),
                                    new RelativeRetrieveArrayImplementation(1),
                                    new ReturnAppenderImplementation(ReturnAppender.ReturnType.INT)))
                    .make();


    Class<?> dynamicType = arr.load(RetrieveFromArray.class.getClassLoader(), ClassLoadingStrategy.Default.WRAPPER)
                    .getLoaded();

    RetrieveFromArray test = (RetrieveFromArray) dynamicType.newInstance();
    int result = test.returnVal(0, 1);
    assertEquals(1, result);

}
 

import net.bytebuddy.implementation.Implementation; //导入依赖的package包/类
@Test
public void testCreateAndAssign() throws Exception {
    DynamicType.Unloaded<CreateAndAssignArray> arr = new ByteBuddy().subclass(CreateAndAssignArray.class)
                    .method(ElementMatchers.isDeclaredBy(CreateAndAssignArray.class))
                    .intercept(new Implementation.Compound(new IntArrayCreation(5), new DuplicateImplementation(),
                                    new RelativeArrayAssignWithValueImplementation(0, 5),
                                    new ReturnAppenderImplementation(ReturnAppender.ReturnType.REFERENCE)))
                    .make();


    Class<?> dynamicType =
                    arr.load(CreateAndAssignArray.class.getClassLoader(), ClassLoadingStrategy.Default.WRAPPER)
                                    .getLoaded();

    CreateAndAssignArray test = (CreateAndAssignArray) dynamicType.newInstance();
    int[] result = test.create();
    assertEquals(5, result[0]);
}
 

import net.bytebuddy.implementation.Implementation; //导入依赖的package包/类
@Test
public void testCreateInt() throws Exception {
    DynamicType.Unloaded<CreateAndAssignIntArray> arr = new ByteBuddy().subclass(CreateAndAssignIntArray.class)
                    .method(ElementMatchers.isDeclaredBy(CreateAndAssignIntArray.class))
                    .intercept(new Implementation.Compound(new ConstantIntImplementation(1),
                                    new StoreIntImplementation(0), new LoadIntegerImplementation(0),
                                    new ReturnAppenderImplementation(ReturnAppender.ReturnType.INT)))
                    .make();


    Class<?> dynamicType =
                    arr.load(CreateAndAssignIntArray.class.getClassLoader(), ClassLoadingStrategy.Default.WRAPPER)
                                    .getLoaded();

    CreateAndAssignIntArray test = (CreateAndAssignIntArray) dynamicType.newInstance();
    int result = test.returnVal();
    assertEquals(1, result);

}
 

import net.bytebuddy.implementation.Implementation; //导入依赖的package包/类
@Override
public AgentBuilder disableClassFormatChanges() {
    return new Default(byteBuddy.with(Implementation.Context.Disabled.Factory.INSTANCE),
            listener,
            circularityLock,
            poolStrategy,
            TypeStrategy.Default.REDEFINE_FROZEN,
            locationStrategy,
            NativeMethodStrategy.Disabled.INSTANCE,
            InitializationStrategy.NoOp.INSTANCE,
            redefinitionStrategy,
            redefinitionDiscoveryStrategy,
            redefinitionBatchAllocator,
            redefinitionListener,
            redefinitionResubmissionStrategy,
            bootstrapInjectionStrategy,
            lambdaInstrumentationStrategy,
            descriptionStrategy,
            fallbackStrategy,
            installationListener,
            ignoredTypeMatcher,
            transformation);
}
 

import net.bytebuddy.implementation.Implementation; //导入依赖的package包/类
@Override
public Bound.ForMethodEnter bind(TypeDescription instrumentedType,
                                 MethodDescription instrumentedMethod,
                                 MethodVisitor methodVisitor,
                                 Implementation.Context implementationContext,
                                 Assigner assigner,
                                 MethodSizeHandler.ForInstrumentedMethod methodSizeHandler,
                                 StackMapFrameHandler.ForInstrumentedMethod stackMapFrameHandler,
                                 StackManipulation exceptionHandler) {
    return new AdviceMethodInliner(instrumentedType,
            instrumentedMethod,
            methodVisitor,
            implementationContext,
            assigner,
            methodSizeHandler,
            stackMapFrameHandler,
            suppressionHandler.bind(exceptionHandler),
            classReader,
            skipDispatcher);
}
 

import net.bytebuddy.implementation.Implementation; //导入依赖的package包/类
/**
 * Creates a new advice method inliner for a method enter.
 *
 * @param instrumentedType      A description of the instrumented type.
 * @param instrumentedMethod    A description of the instrumented method.
 * @param methodVisitor         The method visitor for writing the instrumented method.
 * @param implementationContext The implementation context to use.
 * @param assigner              The assigner to use.
 * @param methodSizeHandler     A handler for computing the method size requirements.
 * @param stackMapFrameHandler  A handler for translating and injecting stack map frames.
 * @param suppressionHandler    A bound suppression handler that is used for suppressing exceptions of this advice method.
 * @param classReader           A class reader for parsing the class file containing the represented advice method.
 * @param skipDispatcher        The skip dispatcher to use.
 */
protected AdviceMethodInliner(TypeDescription instrumentedType,
                              MethodDescription instrumentedMethod,
                              MethodVisitor methodVisitor,
                              Implementation.Context implementationContext,
                              Assigner assigner,
                              MethodSizeHandler.ForInstrumentedMethod methodSizeHandler,
                              StackMapFrameHandler.ForInstrumentedMethod stackMapFrameHandler,
                              SuppressionHandler.Bound suppressionHandler,
                              ClassReader classReader,
                              SkipDispatcher skipDispatcher) {
    super(instrumentedType,
            instrumentedMethod,
            methodVisitor,
            implementationContext,
            assigner,
            methodSizeHandler,
            stackMapFrameHandler,
            suppressionHandler,
            classReader);
    this.skipDispatcher = skipDispatcher;
}
 

import net.bytebuddy.implementation.Implementation; //导入依赖的package包/类
/**
 * Creates a new advice method writer.
 *
 * @param adviceMethod          The advice method.
 * @param instrumentedMethod    The instrumented method.
 * @param offsetMappings        The offset mappings available to this advice.
 * @param methodVisitor         The method visitor for writing the instrumented method.
 * @param implementationContext The implementation context to use.
 * @param methodSizeHandler     A handler for computing the method size requirements.
 * @param stackMapFrameHandler  A handler for translating and injecting stack map frames.
 * @param suppressionHandler    A bound suppression handler that is used for suppressing exceptions of this advice method.
 * @param skipDispatcher        The skip dispatcher to use.
 */
protected ForMethodEnter(MethodDescription.InDefinedShape adviceMethod,
                         MethodDescription instrumentedMethod,
                         List<OffsetMapping.Target> offsetMappings,
                         MethodVisitor methodVisitor,
                         Implementation.Context implementationContext,
                         MethodSizeHandler.ForAdvice methodSizeHandler,
                         StackMapFrameHandler.ForAdvice stackMapFrameHandler,
                         SuppressionHandler.Bound suppressionHandler,
                         Resolved.ForMethodEnter.SkipDispatcher skipDispatcher) {
    super(adviceMethod,
            instrumentedMethod,
            offsetMappings,
            methodVisitor,
            implementationContext,
            methodSizeHandler,
            stackMapFrameHandler,
            suppressionHandler);
    this.skipDispatcher = skipDispatcher;
}
 

import net.bytebuddy.implementation.Implementation; //导入依赖的package包/类
@Override
protected Bound.ForMethodEnter resolve(TypeDescription instrumentedType,
                                       MethodDescription instrumentedMethod,
                                       MethodVisitor methodVisitor,
                                       Implementation.Context implementationContext,
                                       Assigner assigner,
                                       MethodSizeHandler.ForInstrumentedMethod methodSizeHandler,
                                       StackMapFrameHandler.ForInstrumentedMethod stackMapFrameHandler,
                                       StackManipulation exceptionHandler) {
    List<OffsetMapping.Target> offsetMappings = new ArrayList<OffsetMapping.Target>(this.offsetMappings.size());
    for (OffsetMapping offsetMapping : this.offsetMappings) {
        offsetMappings.add(offsetMapping.resolve(instrumentedType,
                instrumentedMethod,
                assigner,
                OffsetMapping.Context.ForMethodEntry.of(instrumentedMethod)));
    }
    return new AdviceMethodWriter.ForMethodEnter(adviceMethod,
            instrumentedMethod,
            offsetMappings,
            methodVisitor,
            implementationContext,
            methodSizeHandler.bindEntry(adviceMethod),
            stackMapFrameHandler.bindEntry(adviceMethod),
            suppressionHandler.bind(exceptionHandler),
            skipDispatcher);
}
 

import net.bytebuddy.implementation.Implementation; //导入依赖的package包/类
@Override
public ModifierAdjustingClassVisitor wrap(TypeDescription instrumentedType,
                                          ClassVisitor classVisitor,
                                          Implementation.Context implementationContext,
                                          TypePool typePool,
                                          FieldList<FieldDescription.InDefinedShape> fields,
                                          MethodList<?> methods,
                                          int writerFlags,
                                          int readerFlags) {
    Map<String, FieldDescription.InDefinedShape> mappedFields = new HashMap<String, FieldDescription.InDefinedShape>();
    for (FieldDescription.InDefinedShape fieldDescription : fields) {
        mappedFields.put(fieldDescription.getInternalName() + fieldDescription.getDescriptor(), fieldDescription);
    }
    Map<String, MethodDescription> mappedMethods = new HashMap<String, MethodDescription>();
    for (MethodDescription methodDescription : CompoundList.<MethodDescription>of(methods, new MethodDescription.Latent.TypeInitializer(instrumentedType))) {
        mappedMethods.put(methodDescription.getInternalName() + methodDescription.getDescriptor(), methodDescription);
    }
    return new ModifierAdjustingClassVisitor(classVisitor,
            typeAdjustments,
            fieldAdjustments,
            methodAdjustments,
            instrumentedType,
            mappedFields,
            mappedMethods);
}