从您的问题来看，您所寻找的事情很简单委托：

From your question it sounds like the thing you are looking for is simple delegation:

class MyString {

  String delegate; // The actual string you delegate to from your class

  public MyString(String delegate) {
    this.delegate = delegate; // Assign the string that backs your class
  }

  int length() {
    return delegate.length(); // Delegate the method call to the string
  }

  // other methods that delegate to the string field
}