Strings in Java are a sequence of characters that are used to represent text. Java provides a built-in class called String to handle strings. A string in Java can be created in several ways, including:
Using string literals: This is the simplest and most common way to create strings in Java. String literals are created by enclosing a sequence of characters within double quotes, like this:
String s = "Hello World!";
Using the String class constructor: Another way to create strings in Java is to use the String class constructor. For example:
String s = new String("Hello World!");
Once you have a string, you can perform various operations on it, including:
Concatenation: You can join two or more strings using the + operator, like this:
String s1 = "Hello";
String s2 = " World!";
String s3 = s1 + s2;
Length: You can find the length of a string using the length() method, like this:
String s = "Hello World!";
int length = s.length();
Substring: You can extract a portion of a string using the substring() method, like this:
String s = "Hello World!";
String sub = s.substring(0, 5);
Character access: You can access individual characters in a string using the square brackets ([]), like this:
String s = "Hello World!";
char c = s.charAt(0);
Comparison: You can compare two strings to see if they are equal using the equals() method, or using the == operator. However, it is important to note that == compares references, not values, while equals() compares the actual contents of the strings.
String s1 = "Hello";
String s2 = "Hello";
if (s1.equals(s2)) {
System.out.println("Strings are equal.");
}
In conclusion, Java’s String class provides a convenient way to handle strings in your programs. Whether you need to create strings, manipulate them, or compare them, Java has the tools you need to get the job done.