个人感觉SingleTraceClassAdapter好像是多余的，一个TraceClassAdapter可以搞定收集Class、Method的信息

private class TraceClassAdapter extends ClassVisitor {
private String className;
private boolean isABSClass = false;
private boolean hasWindowFocusMethod = false;

TraceClassAdapter(int i, ClassVisitor classVisitor) {
super(i, 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;
if ((access & Opcodes.ACC_ABSTRACT) > 0 || (access & Opcodes.ACC_INTERFACE) > 0) {
this.isABSClass = true;
}
//存储一个 类->父类 的map（用于查找Activity的子类）
mCollectedClassExtendMap.put(className, superName);

}

@Override
public MethodVisitor visitMethod(int access, String name, String desc,
String signature, String[] exceptions) {
if (isABSClass) {
return super.visitMethod(access, name, desc, signature, exceptions);
} else {
if (!hasWindowFocusMethod) {
//该方法是否与onWindowFocusChange方法的签名一致（该类中是否复写了onWindowFocusChange方法，Activity不用考虑Class混淆)
hasWindowFocusMethod = mTraceConfig.isWindowFocusChangeMethod(name, desc);
}
//CollectMethodNode中执行method收集操作
return new CollectMethodNode(className, access, name, desc, signature, exceptions);
}
}

@Override
public void visitEnd() {
super.visitEnd();
// collect Activity#onWindowFocusChange
//onWindowFocusChange方法统一给一个-1的方法id
TraceMethod traceMethod = TraceMethod.create(-1, Opcodes.ACC_PUBLIC, className,
TraceBuildConstants.MATRIX_TRACE_ON_WINDOW_FOCUS_METHOD, TraceBuildConstants.MATRIX_TRACE_ON_WINDOW_FOCUS_METHOD_ARGS);
//没有过复写onWindowFocusChange，后续会在该类中插入一个onWindowFocusChange方法，此处先记录一下这个会被插桩的方法
if (!hasWindowFocusMethod && mTraceConfig.isActivityOrSubClass(className, mCollectedClassExtendMap) && mTraceConfig.isNeedTrace(traceMethod.className, mMappingCollector)) {
mCollectedMethodMap.put(traceMethod.getMethodName(), traceMethod);
}
}

}