javastringcloneable

No clone method in String Class

A technical aptitude question

HashMap<String, String> map = new HashMap<String,String>();
String key1 = "key1";
map.put(key1, "value1");
String key2 = key1.clone();
map.put(key2, "value2");

What are the contents of the map object?

I answered it as {key1=value2} but later realized that String doesn't contain clone method.

I wanted to know the reason for the same.

Solution

  • String is an immutable object, so it needn't a clone method since the client code can't change its state inside the String class.

    you can just ref to the original String, for example:

    String key2 = key1;// or using key1 directly instead.