Java String.intern() to create one copy of string value in memory

String.intern() Creates instance of string in memory .
Here are some examples with output.

String str1 = "plus2net";  
String str2 = "plus2net";  
String str3 = new String("plus2net");  
String str4 = str3.intern();          
System.out.println(str1==str2); // true
System.out.println(str2==str3); // false
System.out.println(str4==str2); // true

Practical Use of String.intern() in Java

The String.intern() method is useful for optimizing memory by storing only one instance of identical string values in the string pool. This can be particularly beneficial in the following scenarios:

Large-scale data processing: When dealing with large datasets containing repeated string values (e.g., log analysis or transaction processing), intern() helps reduce memory overhead by avoiding duplicate strings in the heap.
Caching systems: In systems that use string keys, such as caches or configuration managers, intern() ensures that identical keys share the same memory reference, improving memory efficiency.
High-volume text processing: Applications like XML parsers or JSON processors, which encounter repeated tag names or attributes, benefit from reduced memory usage through string interning.

By limiting the creation of duplicate string objects, intern() improves memory management and performance in memory-intensive applications.
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Practical Use of String.intern() in Java