StringBuilder Class in Java

 StringBuilder Class in Java

The `StringBuilder` class in Java represents a mutable sequence of characters. Similar to `StringBuffer`, `StringBuilder` allows for the modification of its content without creating a new object. However, unlike `StringBuffer`, `StringBuilder` is not synchronized, making it more efficient in situations where thread safety is not a concern.

Key Features:

1.Mutability:

   - `StringBuilder` objects are mutable, allowing for the modification of content after creation.

2. Non-Synchronization:

   - Unlike `StringBuffer`, `StringBuilder` is not synchronized. This lack of synchronization improves performance but means it is not thread-safe.

3. Performance Considerations:

   - If thread safety is not a requirement, `StringBuilder` is generally preferred over `StringBuffer` due to its higher performance.

Common Methods:

Here are some commonly used methods of the `StringBuilder` class:

 1. Constructor:

-`StringBuilder()`

  - Creates an empty `StringBuilder` with the default initial capacity (16 characters).

• StringBuilder builder = new StringBuilder();

- `StringBuilder(int capacity)`

  - Creates an empty `StringBuilder` with the specified initial capacity.

• StringBuilder builderWithCapacity = new StringBuilder(30);

 2. Appending Content:

- `append(String str)`

  - Appends the specified string to the end of the `StringBuilder`.

builder.append("Hello");

builder.append(" World");

 3. Inserting Content:

- `insert(int offset, String str)`

  - Inserts the specified string at the specified offset.

• builder.insert(5, " Java");

4. Deleting Content:

- `delete(int start, int end)`

  - Deletes the characters between the specified `start` (inclusive) and `end` (exclusive) indices.

builder.delete(6, 11);

5. Reversing Content:

- `reverse()`

  - Reverses the characters in the `StringBuilder`.

builder.reverse();

6. Capacity Management:

- `capacity()`

  - Returns the current capacity of the `StringBuilder`.

int capacity = builder.capacity();

- `ensureCapacity(int minCapacity)`

  - Ensures that the capacity of the `StringBuilder` is at least equal to the specified minimum capacity.

builder.ensureCapacity(50);

7. Converting to String:

- `toString()`

  - Converts the `StringBuilder` to a `String`.

String result = builder.toString();

Example Usage:

// Creating a StringBuilder

StringBuilder builder = new StringBuilder();

// Appending content

builder.append("Hello");

builder.append(" World");

// Inserting content

builder.insert(5, " Java");

// Deleting content

builder.delete(6, 11);

// Reversing content

builder.reverse();

// Converting to String

String result = builder.toString();

The `StringBuilder` class provides a non-synchronized alternative to `StringBuffer` for situations where thread safety is not a concern, offering better performance in such scenarios.