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In this code example we are going to learn how to find a specific word or text inside a string. For this example we will utilize the java.lang.String class. The String class provides a method called String.indexOf(). It takes an argument of a String, which is the sub string that we want to find in […]
In the previous example How do I know if a character is lowercase?, we’ve learned how to use the Character.isLowerCase() method. Now we will learn how to use the other method, which is the Character.isUpperCase() to determine if a letter is in an uppercase form. This method also return a boolean value that indicates whether […]
In this example you are going to learn another example on using the java.lang.Character class. The Character.isLowerCase() method can be used to determine if a letter is a lowercase letter. This method takes a char as argument and return a boolean value. If it returns true it means the character is in lowercase form. And […]
In the previous example you’ve learned how to use the Character.isDigit() method to check if a character representing a digit. In this example you will learn how to check if a character representing a letter. You can use the Character.isLetter(char c) method to check if a character is a valid letter. This method will return […]
For validation purposes we might need to check if data entered by our users is a valid data for our application to process. A simple mechanism for checking if a character inputted is a digit or not can be done by using the java.lang.Character class isDigit(char c) method. In this example you will learn how […]
In this example we are going to learn how to find out if an ArrayList object contains the specified element. To check if an ArrayList object contains the specified element we can use the contains(Object o) method. This method returns a boolean true when the specified element is found in the ArrayList, otherwise return false. […]
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