Convert Characters to Upper Case - A Java Code Example

To convert all lower case characters in a string to upper case, use the method toUpperCase() of the String class.
The example below shows how to use it. Note that the method returns a String so you'll need to assign the return value of the method to a variable (in this case the same variable).

/**
* Main.java
*
* @author www.javadb.com
*/
public class Main {

    /**
     * Converts all lower case characters to upper case
     */
    public void stringToUpperCase() {

        String str = "All Lower Case Characters In This String Will Be Converted To Upper Case";

        str = str.toUpperCase();

        System.out.println(str);
    }

    /**
     * Starts the program
     *
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        new Main().stringToUpperCase();
    }
}

The result of the above code when executed:

ALL LOWER CASE CHARACTERS IN THIS STRING WILL BE CONVERTED TO UPPER CASE

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