Java · question
Q.04 of 89
What is the difference between String, StringBuilder, and StringBuffer?
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- String: Immutable, thread-safe. Each modification creates a new object.
- StringBuilder: Mutable, not thread-safe, faster for single-threaded string operations.
- StringBuffer: Mutable, thread-safe (synchronized), slower due to synchronization overhead.
String str = "Hello";
str += " World"; // Creates new String object
StringBuilder sb = new StringBuilder("Hello");
sb.append(" World"); // Modifies existing buffer
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