STRING

Strings, which are widely used in Java programming, are a sequence of characters. In the Java programming language, strings are objects.
The Java platform provides the String class to create and manipulate strings.

Creating Strings:

java strings

The most direct way to create a string is to write:
align="justify" class="runningfont">String greeting = "Hello world!"
align="justify" class="runningfont">Whenever it encounters a string literal in your code, the compiler creates a String object with its value in this case, "Hello world!'.

As with any other object, you can create String objects by using the new keyword and a constructor. The String class has eleven constructors that allow you to provide the initial value of the string using different sources, such as an array of characters:

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public class StringDemo
    {
        public static    void main(String args[])
            {
                char[]    helloArray = { 'h', 'e', 'l', 'l', 'o', '.'};<br>
                String    helloString = new String(helloArray);<br>
                System.out.println( helloString );<br>
            }
    }

This would produce following result:

hello.

Note: The String class is immutable, so that once it is created a String object cannot be changed. If there is a necessity to make alot of modifications to Strings of characters then you should use StringBuffer & StringBuilder Classes.

String Length:
Methods used to obtain information about an object are known as accessor methods. One accessor method that you can use with strings is the length() method, which returns the number of characters contained in the string object.

After the following two lines of code have been executed, len equals 17

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public class StringDemo
    {
        public static    void main(String args[])
            {
                String    palindrome = "Dot saw I was Tod";
                int len =    palindrome.length();
                System.out.println( "String Length is : " + len );
            }
    }

This would produce following result:

String Length is : 17