How to Create CaseInsensitiveString Instances: Constructor or Static Factory Method?

Java Strings: Finger Pointing at "String s = new String("silly")"

While venturing into the world of Java programming, a query emerges regarding the appropriate creation of String objects. The concern stems from the notion of avoiding unnecessary String creation by utilizing literals instead of "new String(...)" calls. However, this guidance seems to contradict the usage of custom string classes such as CaseInsensitiveString.

Question 1: Why is the usage of "new CaseInsensitiveString(...)" necessary?

In contrast to the simplistic case of String, CaseInsensitiveString is a custom class defined by the programmer. Instances of this class can only be created through the designated constructor "CaseInsensitiveString(...)". As Java does not support copy constructors, the constructor must be explicitly invoked to initialize the object's internal state.

Question 2: Adapting CaseInsensitiveString to behave like String

While the default behavior of CaseInsensitiveString necessitates the use of its constructor, there are potential avenues to mimic the simplified syntax of the built-in String class.

With Extension:

• Extending String would allow CaseInsensitiveString to inherit its behavior.
• Overriding the static factory method of String would enable direct instantiation from literals.
• However, this approach tightly couples CaseInsensitiveString to the String class, limiting its flexibility and introducing potential maintenance issues.

Without Extension:

• Implementing a custom "valueOf(...)" static method would allow for the creation of CaseInsensitiveString instances from literals.
• This preserves the independence of CaseInsensitiveString from the String class while providing a more convenient syntax for initialization.
• Within the "valueOf(...)" method, a new instance of CaseInsensitiveString would be created using the passed literal.

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