String in Java

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 In Java, a `String` is an object that represents a sequence of characters. It belongs to the `java.lang` package, and it's widely used for handling textual data. Here are some essential methods associated with the `String` class:


1. **Creating Strings:**

   - `String myString = "Hello, World!";` - Creates a string literal.

   - `String anotherString = new String("Java");` - Creates a string using the `new` keyword.


2. **Length:**

   - `int length = myString.length();` - Returns the length of the string.


3. **Concatenation:**

   - `String combined = myString + " " + anotherString;` - Concatenates strings.


4. **Substring:**

   - `String sub = myString.substring(7);` - Extracts a substring from the original string.


5. **Concatenation with Other Data Types:**

   - `int number = 42;`

   - `String result = "The answer is " + number;` - You can concatenate strings with other data types.


6. **Comparison:**

   - `boolean isEqual = myString.equals(anotherString);` - Compares two strings for equality.

   - `int compareResult = myString.compareTo(anotherString);` - Compares two strings lexicographically.


7. **Searching:**

   - `int index = myString.indexOf("World");` - Finds the index of a substring.


8. **Conversion:**

   - `int num = Integer.parseInt("123");` - Converts a string to an integer.


9. **Modification:**

   - `String upperCase = myString.toUpperCase();` - Converts the string to uppercase.


10. **Trimming:**

    - `String trimmed = myString.trim();` - Removes leading and trailing whitespaces.


These are just a few examples, and there are many more methods available in the `String` class for various operations. Strings in Java are immutable, meaning once a string is created, it cannot be changed. If you perform operations that seem to modify a string, they actually create a new string.

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