public class TimeStatisticsAdapter extends AdviceAdapter {
protected TimeStatisticsAdapter(int api, MethodVisitor methodVisitor, int access, String name, St
super(api, methodVisitor, access, name, descriptor);
}
@Override
protected void onMethodEnter() {
// 进入函数时调用TimeStatistics的静态方法start
super.visitMethodInsn(Opcodes.INVOKESTATIC, "com/example/aop/agent/TimeStatistics", "start",
super.onMethodEnter();
}
@Override
protected void onMethodExit(int opcode) {
// 退出函数时调用TimeStatistics的静态方法end
super.onMethodExit(opcode);
super.visitMethodInsn(Opcodes.INVOKESTATIC, "com/example/aop/agent/TimeStatistics", "end", "
}
}
public class TimeStatistics {
public static ThreadLocal<Long> t = new ThreadLocal<>();
public static void start() {
t.set(System.currentTimeMillis());
}
public static void end() {
long time = System.currentTimeMillis() - t.get();
System.out.println(Thread.currentThread().getStackTrace()[2] + " spend: " + time);
}
}
public class AgentMain {
// premain()函数中注册MyClassFileTransformer转换器
public static void premain (String agentArgs, Instrumentation instrumentation) {
System.out.println("premain方法");
instrumentation.addTransformer(new MyClassFileTransformer(), true);
}
}