2019-04-14

自定义plugin给方法统计时间（插桩）

####1、创建新project

创建一个新的project，默认创建就行，名字叫testPlugin

先大致看一下工程目录如下：

####2、使用buildSrc的方式创建自定义plugin

为什么使用buildSrc，因为理解简单，也可以使用其他方法，比如上传到本地repo
官网说明了如何自定义plugin
https://guides.gradle.org/writing-gradle-plugins/
https://docs.gradle.org/current/userguide/custom_plugins.html

没看懂的看同行的解释，自定义Android Gradle插件的3种方式
https://blog.csdn.net/brycegao321/article/details/82754014

另外：自定义plugin可以groovy，java，kotlin语言编写
需要在build.gradle引入
app plugin: ‘java’
app plugin: ‘groovy’
app plugin: ‘kotlin’

试了一下创建一个androidlib，然后在main后面创建一个groovy文件夹，再写一个build.gradle

*****build.gradle*****
buildscript {
    ext.android_gradle_plugin_version = '3.1.3'
    repositories {
        jcenter()
        google()
    }
    dependencies {
    }
}

repositories {
    jcenter()
    google()
}

apply plugin: 'java'
apply plugin: 'groovy'

dependencies {
    implementation gradleApi()
    implementation localGroovy()
    implementation "com.android.tools.build:gradle:$android_gradle_plugin_version"
    implementation "com.android.tools.build:gradle-api:$android_gradle_plugin_version"
}

但是结束报错了，一堆红色的log

block1
buildSrc会出现Plugin with id 'android-library' not found
需要 apply plugin: 'groovy'

block2
buildSrc也出现Duplicate root element
直接创建文件夹，不要创建android library

tip: id写法
buildSrc/src/main/resources/META-INF/gradle-plugins/org.example.greeting.properties
放这个映射文件后就可以用id的写法

正确的创建buildSrc方法

1、直接创建buildSrc文件夹，
2、创建src文件夹，
3、创建main文件夹，
4、创建groovy文件夹，在这里面写自定义plugin
5、创建resources文件夹，接着META-INF，接着gradle-plugins，
在文件夹gradle-plugins里面新建一个com.kalengo.customplugin.properties，里面写名称implementation-class=CustomPlugin
这两个名称在app的build.gradle引用plugin的时候是两种写法，一种是包名，一种是id

buildSrc的目录参考

####自定义plugin
自定义plugin需要implements Plugin
覆盖void apply(Project project) 方法

可以在方法里面做添加task的操作
//./gradlew -q hello
//测试build.gradle的参数获取
def extension = project.extensions.create('greeting', GreetingPluginExtension)
project.task('hello') {
    doLast {
        println extension.message
        println extension.greeter
    }
}

也可以定义transform对class进行特殊处理
//自定义transform进行处理
def android = project.extensions.getByType(AppExtension)
android.registerTransform(new CustomTransform(project))

####自定义transform

首先需要在自定义plugin的apply方法里面注册transform
//自定义transform进行处理
def android = project.extensions.getByType(AppExtension)
android.registerTransform(new CustomTransform(project))

自定义transform要extends Transform ，并实现方法
public abstract String getName();
public abstract Set<ContentType> getInputTypes();
Set<QualifiedContent.ContentType> getInputTypes()
Set<? super QualifiedContent.Scope> getScopes()
boolean isIncremental()
void transform(Context context, Collection<TransformInput> inputs, Collection<TransformInput> referencedInputs, TransformOutputProvider outputProvider, boolean isIncremental) throws IOException, TransformException, InterruptedException

此时如果transform是个空方法，build 后就会报错，
需要在transform加入复制文件的代码，作用是将class复制到dest的目录，也就是说应用自定义transform后需要自己处理复制class文件的流程。
否则的话会出现打出来的包classes.dex是0字节

//不管对class处理不处理，都要copy file
def dest = outputProvider.getContentLocation(directoryInput.name,
        directoryInput.contentTypes, directoryInput.scopes,
        Format.DIRECTORY)
FileUtils.copyDirectory(directoryInput.file, dest)
    
def dest = outputProvider.getContentLocation(jarInput.name,
        jarInput.contentTypes, jarInput.scopes, Format.JAR)
FileUtils.copyFile(jarInput.file, dest)

####对某个注解进行asm方法代码插桩

在自定义transtorm方法里要这样写

void transform(Context context, Collection<TransformInput> inputs, Collection<TransformInput> referencedInputs, TransformOutputProvider outputProvider, boolean isIncremental) throws IOException, TransformException, InterruptedException {
        super.transform(context, inputs, referencedInputs, outputProvider, isIncremental)
        println('hello transform')
        //遍历input
        inputs.each { TransformInput input ->
            //遍历文件input
            input.directoryInputs.each { DirectoryInput directoryInput ->
                if (directoryInput.file.isDirectory()) {
                    directoryInput.file.eachFileRecurse { File file ->
                        def name = file.name
                        //过滤，只处理该处理都class
                        if (name.endsWith(".class") && !name.startsWith("R\$") &&
                                "R.class" != name && "BuildConfig.class" != name) {
                            println(name)

                            ClassReader cr = new ClassReader(file.bytes)
                            ClassWriter cw = new ClassWriter(cr, ClassWriter.COMPUTE_MAXS)
                            ClassVisitor cv = new MethodTimeClassVisitor(cw)

                            cr.accept(cv, ClassReader.EXPAND_FRAMES)

                            byte[] code = cw.toByteArray()

                            FileOutputStream fos = new FileOutputStream(
                                    file.parentFile.absolutePath + File.separator + name)
                            fos.write(code)
                            fos.close()
                        }

                    }
                }
                //不管对class处理不处理，都要copy file
                def dest = outputProvider.getContentLocation(directoryInput.name,
                        directoryInput.contentTypes, directoryInput.scopes,
                        Format.DIRECTORY)
                FileUtils.copyDirectory(directoryInput.file, dest)
            }
            //遍历jar包input
            input.jarInputs.each { JarInput jarInput ->
                //不管对jar处理不处理，都要copy file
                def dest = outputProvider.getContentLocation(jarInput.name,
                        jarInput.contentTypes, jarInput.scopes, Format.JAR)
                FileUtils.copyFile(jarInput.file, dest)
            }
        }

    }

MethodTimeClassVisitor 需要extends ClassVisitor实现visitMethod方法

1 2	protected void onMethodEnter() protected void onMethodExit(int opcode)

上面这两个方法就是分布在方法前后调用的。

那里面的asm代码如何写呢？

先在项目里新建一个TestAsm.java的文件
写一些方法，比如

public class TestAsm {
    private void methodTimeStart() {
        System.out.println("========start=========");
        TimeCache.setStartTime("method", System.nanoTime());
    }
    private void methodTimeDnd() {
        TimeCache.setEndTime("method", System.nanoTime());
        System.out.println(TimeCache.getCostTime("method"));
        System.out.println("========end=========");
    }
}

这时要用到bytecode outline神器了，使用结果如下图

然后ide->code->show bytecode outline按钮
在右侧的asm面板选择ASMified的tab，要把生成的asm代码复制

{
            mv = cw.visitMethod(ACC_PRIVATE, "methodTimeStart", "()V", null, null);
            mv.visitCode();
            Label l0 = new Label();
            mv.visitLabel(l0);
            mv.visitLineNumber(11, l0);
            mv.visitFieldInsn(GETSTATIC, "java/lang/System", "out", "Ljava/io/PrintStream;");
            mv.visitLdcInsn("========start=========");
            mv.visitMethodInsn(INVOKEVIRTUAL, "java/io/PrintStream", "println", "(Ljava/lang/String;)V", false);
            Label l1 = new Label();
            mv.visitLabel(l1);
            mv.visitLineNumber(12, l1);
            mv.visitLdcInsn("method");
            mv.visitMethodInsn(INVOKESTATIC, "java/lang/System", "nanoTime", "()J", false);
            mv.visitMethodInsn(INVOKESTATIC, "com/kalengo/commonlib/TimeCache", "setStartTime", "(Ljava/lang/String;J)V", false);
            Label l2 = new Label();
            mv.visitLabel(l2);
            mv.visitLineNumber(13, l2);
            mv.visitInsn(RETURN);
            Label l3 = new Label();
            mv.visitLabel(l3);
            mv.visitLocalVariable("this", "Lcom/kalengo/testplugin/TestAsm;", null, l0, l3, 0);
            mv.visitMaxs(3, 1);
            mv.visitEnd();
        }
        {
            mv = cw.visitMethod(ACC_PRIVATE, "methodTimeDnd", "()V", null, null);
            mv.visitCode();
            Label l0 = new Label();
            mv.visitLabel(l0);
            mv.visitLineNumber(15, l0);
            mv.visitLdcInsn("method");
            mv.visitMethodInsn(INVOKESTATIC, "java/lang/System", "nanoTime", "()J", false);
            mv.visitMethodInsn(INVOKESTATIC, "com/kalengo/commonlib/TimeCache", "setEndTime", "(Ljava/lang/String;J)V", false);
            Label l1 = new Label();
            mv.visitLabel(l1);
            mv.visitLineNumber(16, l1);
            mv.visitFieldInsn(GETSTATIC, "java/lang/System", "out", "Ljava/io/PrintStream;");
            mv.visitLdcInsn("newFunc");
            mv.visitMethodInsn(INVOKESTATIC, "com/kalengo/commonlib/TimeCache", "getCostTime", "(Ljava/lang/String;)Ljava/lang/String;", false);
            mv.visitMethodInsn(INVOKEVIRTUAL, "java/io/PrintStream", "println", "(Ljava/lang/String;)V", false);
            Label l2 = new Label();
            mv.visitLabel(l2);
            mv.visitLineNumber(17, l2);
            mv.visitFieldInsn(GETSTATIC, "java/lang/System", "out", "Ljava/io/PrintStream;");
            mv.visitLdcInsn("========end=========");
            mv.visitMethodInsn(INVOKEVIRTUAL, "java/io/PrintStream", "println", "(Ljava/lang/String;)V", false);
            Label l3 = new Label();
            mv.visitLabel(l3);
            mv.visitLineNumber(18, l3);
            mv.visitInsn(RETURN);
            Label l4 = new Label();
            mv.visitLabel(l4);
            mv.visitLocalVariable("this", "Lcom/kalengo/testplugin/TestAsm;", null, l0, l4, 0);
            mv.visitMaxs(3, 1);
            mv.visitEnd();
        }

注意要去除一些代码，比如RETURN相关的，比如RETURN后面的，比如cw.visitMethod

整理后就变成

@Override
            protected void onMethodEnter() {
                if (inject) {
                    Label l0 = new Label();
                    mv.visitLabel(l0);
                    mv.visitLineNumber(11, l0);
                    mv.visitFieldInsn(GETSTATIC, "java/lang/System", "out", "Ljava/io/PrintStream;");
                    mv.visitLdcInsn("========start=========");
                    mv.visitMethodInsn(INVOKEVIRTUAL, "java/io/PrintStream", "println", "(Ljava/lang/String;)V", false);
                    Label l1 = new Label();
                    mv.visitLabel(l1);
                    mv.visitLineNumber(12, l1);
                    mv.visitLdcInsn(name);
                    mv.visitMethodInsn(INVOKESTATIC, "java/lang/System", "nanoTime", "()J", false);
                    mv.visitMethodInsn(INVOKESTATIC, "com/kalengo/commonlib/TimeCache", "setStartTime", "(Ljava/lang/String;J)V", false);
                }
            }

            @Override
            protected void onMethodExit(int opcode) {
                if (inject) {
                    Label l0 = new Label();
                    mv.visitLabel(l0);
                    mv.visitLineNumber(15, l0);
                    mv.visitLdcInsn(name);
                    mv.visitMethodInsn(INVOKESTATIC, "java/lang/System", "nanoTime", "()J", false);
                    mv.visitMethodInsn(INVOKESTATIC, "com/kalengo/commonlib/TimeCache", "setEndTime", "(Ljava/lang/String;J)V", false);
                    Label l1 = new Label();
                    mv.visitLabel(l1);
                    mv.visitLineNumber(16, l1);
                    mv.visitFieldInsn(GETSTATIC, "java/lang/System", "out", "Ljava/io/PrintStream;");
                    mv.visitLdcInsn(name);
                    mv.visitMethodInsn(INVOKESTATIC, "com/kalengo/commonlib/TimeCache", "getCostTime", "(Ljava/lang/String;)Ljava/lang/String;", false);
                    mv.visitMethodInsn(INVOKEVIRTUAL, "java/io/PrintStream", "println", "(Ljava/lang/String;)V", false);
                    Label l2 = new Label();
                    mv.visitLabel(l2);
                    mv.visitLineNumber(17, l2);
                    mv.visitFieldInsn(GETSTATIC, "java/lang/System", "out", "Ljava/io/PrintStream;");
                    mv.visitLdcInsn("========end=========");
                    mv.visitMethodInsn(INVOKEVIRTUAL, "java/io/PrintStream", "println", "(Ljava/lang/String;)V", false);
                }
            }

然后就可以build了。在这里可以看到经过插桩后的代码

TestPlugin/app/build/intermediates/classes/release/com/kalengo/testplugin

public class Logic {

    @MethodTime
    public void test() {
        for (int i = 0;i < 1000;i++) {
            System.out.println();
        }
    }

    @MethodTime
    public void test2() {
        for (int i = 0;i < 100;i++) {
            System.out.println();
        }
    }
}



public class Logic {
    public Logic() {
    }

    @MethodTime
    public void test() {
        System.out.println("========start=========");
        TimeCache.setStartTime("test", System.nanoTime());

        for(int i = 0; i < 1000; ++i) {
            System.out.println();
        }

        TimeCache.setEndTime("test", System.nanoTime());
        System.out.println(TimeCache.getCostTime("test"));
        System.out.println("========end=========");
    }

    @MethodTime
    public void test2() {
        System.out.println("========start=========");
        TimeCache.setStartTime("test2", System.nanoTime());

        for(int i = 0; i < 100; ++i) {
            System.out.println();
        }

        TimeCache.setEndTime("test2", System.nanoTime());
        System.out.println(TimeCache.getCostTime("test2"));
        System.out.println("========end=========");
    }
}

然后就可以assemble了。在这里可以看到经过插桩后的代码

TestPlugin/app/build/intermediates/transforms/CustomTransform/debug/31/com/kalengo/testplugin


public class Logic {
    public Logic() {
    }

    @MethodTime
    public void test() {
        System.out.println("========start=========");
        TimeCache.setStartTime("test", System.nanoTime());

        for(int i = 0; i < 1000; ++i) {
            System.out.println();
        }

        TimeCache.setEndTime("test", System.nanoTime());
        System.out.println(TimeCache.getCostTime("test"));
        System.out.println("========end=========");
    }

    @MethodTime
    public void test2() {
        System.out.println("========start=========");
        TimeCache.setStartTime("test2", System.nanoTime());

        for(int i = 0; i < 100; ++i) {
            System.out.println();
        }

        TimeCache.setEndTime("test2", System.nanoTime());
        System.out.println(TimeCache.getCostTime("test2"));
        System.out.println("========end=========");
    }
}

至于混淆，那就要反编译去看了，或者可以直接在ide里面点击apk包进行查看。

最后，运行一下,结果出来了。

1 2	04-14 19:50:30.503 4162-4162/com.kalengo.testplugin I/System.out: method: test time 367.292 ms 04-14 19:50:30.503 4162-4162/com.kalengo.testplugin I/System.out: method: test2 time 26.041 ms