Strings in Java are immutable, which means that once a string object is created, its value cannot be changed. Here are the key points about string immutability in Java:
String objects are stored in the String pool in the heap memory. When a new string is created, the JVM checks if an identical string already exists in the pool. If so, it reuses the existing object instead of creating a new one[1][2].
Immutability ensures that strings can be safely shared between multiple threads without synchronization issues[1][2][4]. It also enables caching of strings for better performance[2].
Immutability provides security benefits. For example, it prevents malicious modification of strings used for database connections, class loading, or other sensitive operations[2][4].
When a string operation like concatenation is performed, a new string object is created with the modified value. The original string remains unchanged[1][3][4].
