前序步骤参考链接：学习自定义gradle插件
使用 ASM，插入字节码到 Activity 文件
1.在 asm_lifecycle_plugin 的 build.gradle 中，添加对 ASM 的依赖，如下：
apply plugin: 'maven'
apply plugin:'groovy'
dependencies {
compile gradleApi()
compile localGroovy()
compile 'com.android.tools.build:gradle:3.4.2'
//asm相关依赖
implementation 'org.ow2.asm:asm:7.1'
implementation 'org.ow2.asm:asm-commons:7.1'
}
...
- 在asm_lifecycle_pluginmodule中的src/main/java目录下创建包com.okay.asm，并分别创建LifecycleClassVisitor.java和LifeCycleMethodVisitor.java文件
public class LifeCycleClassVisitor extends ClassVisitor {
private String className;
private String superName;
public LifeCycleClassVisitor(int api) {
super(api);
}
public LifeCycleClassVisitor(int api, ClassVisitor classVisitor) {
super(api, classVisitor);
}
@Override
public void visit(int version, int access, String name, String signature, String superName, String[] interfaces) {
super.visit(version, access, name, signature, superName, interfaces);
this.className = name;
this.superName = superName;
}
@Override
public MethodVisitor visitMethod(int access, String name, String descriptor, String signature, String[] exceptions) {
System.out.println("ClassVisitor visitMethod name---"+name+",super name = "+superName);
MethodVisitor mv = cv.visitMethod(access, name, descriptor, signature, exceptions);
if (superName.equals("androidx/appcompat/app/AppCompatActivity")){
if (name.startsWith("onCreate")){
//处理这个方法
return new LifeCycleMethodVisitor(mv,className,name);
}
}
return mv;
}
}
public class LifeCycleMethodVisitor extends MethodVisitor {
private String className;
private String methodName;
public LifeCycleMethodVisitor(MethodVisitor mv, String className, String name) {
super(Opcodes.ASM5, mv);
this.className = className;
this.methodName = name;
}
/**
* 方法执行前先走这个
*/
@Override
public void visitCode() {
super.visitCode();
System.out.println("LifeCycleMethodVisitor -- :visitCode");
//LDC "SizeConvertUtil"
//LDC "className---->MethodName"
//INVOKESTATIC android/util/Log.i (Ljava/lang/String;Ljava/lang/String;)I
//POP
mv.visitLdcInsn("zyl_TAG");
mv.visitLdcInsn(className + "-------->" + methodName);
mv.visitMethodInsn(Opcodes.INVOKESTATIC, "android/util/Log", "i", "(Ljava/lang/String;Ljava/lang/String;)I", false);
mv.visitLdcInsn(Opcodes.POP);
}
}
- 修改 LifeCycleTransform 的 transform 方法，并将需要插桩的字节码插入到 MainActivity.class 文件中的transform方法：
/**
*
* @param transformInvocation
* @throws TransformException* @throws InterruptedException* @throws IOException
*/
@Override
void transform(TransformInvocation transformInvocation) throws TransformException, InterruptedException, IOException {
super.transform(transformInvocation)
//拿到所有的class文件
def inputs = transformInvocation.inputs
def provider = transformInvocation.outputProvider
inputs.each { transformInput ->
transformInput.directoryInputs.each { DirectoryInput directoryInput ->
File dir = directoryInput.file
if (dir) {
dir.traverse(type: FileType.FILES, nameFilter: ~/.*\.class/) { File file ->
System.out.println("find class: " + file.name)
//对class文件进行读取
ClassReader classReader = new ClassReader(file.bytes)
//对class文件进行写入
ClassWriter classWriter = new ClassWriter(classReader, ClassWriter.COMPUTE_MAXS)
//访问相应的内容
ClassVisitor classVisitor = new LifeCycleClassVisitor(classWriter)
classReader.accept(classVisitor, ClassReader.EXPAND_FRAMES)
byte[] bytes = classWriter.toByteArray()
//通过文件流写入的形式覆盖掉原有的内容，实现class的改写
FileOutputStream outputStream = new FileOutputStream(file.path)
outputStream.write(bytes)
outputStream.close()
}
}
//处理完输入文件后把输出传递给下一个文件
def location = provider.getContentLocation(directoryInput.name, directoryInput.contentTypes, directoryInput.scopes, Format.DIRECTORY)
FileUtils.copyDirectory(directoryInput.file,location)
}
}
}
- 上面几步如果一切执行顺利，那接下来就可以在点击uploadArchives重新部署LifeCyclePlugin。注意：重新部署时，需要先在appmodule的build.gradle中将插件依赖注释，否则报错。部署成功之后，重新在app中依赖自定义插件并运行主项目，当 MainActivity 被打开时，在 logcat中过滤zyl_TAG：
04-08 10:11:07.699 18156-18156/com.okay.asmlifecycle I/zyl_TAG: com/okay/asmlifecycle/MainActivity-------->onCreate
问题与总结
1.运行报错
java.lang.NoClassDefFoundError: Failed resolution of: Landroidx/appcompat/R$drawable;
at androidx.appcompat.widget.AppCompatDrawableManager$1.(AppCompatDrawableManager.java:63)
at androidx.appcompat.widget.AppCompatDrawableManager.preload(AppCompatDrawableManager.java:57)
at androidx.appcompat.app.AppCompatDelegateImpl.(AppCompatDelegateImpl.java:328)
at androidx.appcompat.app.AppCompatDelegateImpl.(AppCompatDelegateImpl.java:278)
at androidx.appcompat.app.AppCompatDelegate.create(AppCompatDelegate.java:221)
at androidx.appcompat.app.AppCompatActivity.getDelegate(AppCompatActivity.java:543)
at androidx.appcompat.app.AppCompatActivity.attachBaseContext(AppCompatActivity.java:98)
at android.app.Activity.attach(Activity.java:6028)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2462)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2608)
at android.app.ActivityThread.access$800(ActivityThread.java:178)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1470)
at android.os.Handler.dispatchMessage(Handler.java:111)
at android.os.Looper.loop(Looper.java:194)
at android.app.ActivityThread.main(ActivityThread.java:5637)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:959)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:754)
Caused by: java.lang.ClassNotFoundException: Didn't find class "androidx.appcompat.R$drawable" on path: DexPathList[[zip file "/data/app/com.okay.asmlifecycle-1/base.apk"],nativeLibraryDirectories=[/vendor/lib64, /system/lib64]]
at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:56)
at java.lang.ClassLoader.loadClass(ClassLoader.java:511)
at java.lang.ClassLoader.loadClass(ClassLoader.java:469)
at androidx.appcompat.widget.AppCompatDrawableManager$1.(AppCompatDrawableManager.java:63)
at androidx.appcompat.widget.AppCompatDrawableManager.preload(AppCompatDrawableManager.java:57)
at androidx.appcompat.app.AppCompatDelegateImpl.(AppCompatDelegateImpl.java:328)
at androidx.appcompat.app.AppCompatDelegateImpl.(AppCompatDelegateImpl.java:278)
at androidx.appcompat.app.AppCompatDelegate.create(AppCompatDelegate.java:221)
at androidx.appcompat.app.AppCompatActivity.getDelegate(AppCompatActivity.java:543)
at androidx.appcompat.app.AppCompatActivity.attachBaseContext(AppCompatActivity.java:98)
at android.app.Activity.attach(Activity.java:6028)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2462)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2608)
at android.app.ActivityThread.access$800(ActivityThread.java:178)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1470)
at android.os.Handler.dispatchMessage(Handler.java:111)
at android.os.Looper.loop(Looper.java:194)
at android.app.ActivityThread.main(ActivityThread.java:5637)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:959)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:754)
Suppressed: java.lang.ClassNotFoundException: androidx.appcompat.R$drawable
at java.lang.Class.classForName(Native Method)
at java.lang.BootClassLoader.findClass(ClassLoader.java:781)
at java.lang.BootClassLoader.loadClass(ClassLoader.java:841)
at java.lang.ClassLoader.loadClass(ClassLoader.java:504)
... 20 more
Caused by: java.lang.NoClassDefFoundError: Class not found using the boot class loader; no stack available
- 解决方法 替换了app的gradle依赖版本classpath 'com.android.tools.build:gradle:3.4.2'，之前是3.6.2。