What type does string belong to in java?

String is a reference type in Java that represents text data. Once created, its content cannot be modified. Specifically, it belongs to the java.lang package, uses Unicode encoding to represent characters, and uses a String Pool to optimize memory usage and performance. At the same time, immutable String provides stability and avoids accidental modifications, while StringBuilder allows text data to be modified, improving performance and efficiency.

The type of String in Java

String is an object that represents text data in Java. It is an immutable type, which means that once created, its contents cannot be modified.

Primitive data types:

Strictly speaking, String is not a primitive data type in Java. Primitive data types are basic data types such as int, double, and boolean. They store values ​​directly in memory.

Reference type:

String is a reference type. Reference types store a reference to the actual object in memory rather than the actual value. So when we create a String object, we are actually creating a reference to the address of that object in heap memory.

Specifically:

• String class belongs to the java.lang package.
• String objects represent characters using Unicode encoding.
• String is immutable, which means that once created, its content cannot be modified. To modify text data, a new String object must be created.

Other related concepts:

• String Pool: There is a String pool in Java, which is a storage created A hash table of String objects. Every time a new String object is created, the Java Virtual Machine (JVM) first checks whether the object exists in the String pool. If it exists, the JVM will return a reference to the existing object instead of creating a new object. This optimizes memory usage and improves performance.
• StringBuilder: StringBuilder is a mutable version of String. It allows you to modify text data without having to create a new String object every time. This is useful for operations that require frequent modification of text data.

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