How should I copy Strings in Java?

Delving into string immutability

String immutability is a core concept in Java. Once a string is created, it cannot be altered. This offers:

• Security: The unchangeable nature prevents unauthorized alterations.
• Synchronization: Safe to use in multithreaded scenarios.
• Memory optimization: The JVM is smart enough to adroitly reuse strings.

When assigning a string to a new reference, no extra memory is allocated:

String str1 = "Hello, World!";
String str2 = str1; // Plays "Follow the Leader" with str1
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Reducing object redundancy & efficient copying

Using new String() is not often needed and might induce inefficiency. This spawns a new String instance, regardless of an identical one existing in the String pool. Unchecked use might trigger the infamous Java.lang.OutOfMemoryError.

Harnessing string interning

The intern() method assists in avoiding memory wastage by reusing strings from the String pool:

String s1 = "Debugging is like being a detective";
String s2 = new String("Debugging is like being a detective").intern(); // "Sherlock Holmes" mode activated!
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Remember, string interning is not all roses. Unabated use might inflate the String pool, leading to Memory Overhead.

Why clone() isn't the hero we need, nor the one we deserve!

In Java, the clone() method's utility for strings is dubious. Remember, your strings are adamant in nature, they won't change. Cloning would merely return identical references, which is as useless as a chocolate teapot!

Use cases for creating unique copies

Assignment is your reliable friend for most scenarios. But, new string creation could be handy for substrings or intensive text manipulations:

String processed = new String(subString.trim());
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processed here lets JVM clean out trimmed portions, enhancing your garbage collection.

Strategies for optimized string copying

Good practices

• Use new String() when a unique object is mandatory.
• Use string interning perceptively to avoid wasting memory.
• Keep an eye for when garbage collection could get affected by your string copying strategy.

Handling exceptions

• In sensitive apps, watch your data endpoints to avoid accidental data leaks.
• Note the memory implications of creating new string instances, especially while dealing with large text bodies.

Advanced scenarios

Special circumstances that demand advanced string copying techniques can include sensitive data handling or memory optimizations:

• Arrays.copyOfRange() allows copying a particular part from a string.
• Applying Serialization can provide an advanced method of string copying in specific situations.

References