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I have the user entering a single character into the program and it is stored as a string. I would like to know how I could check to see if the character that was entered is a letter or a digit. I have an if statement, so if its a letter its prints that it's a letter, and the same for a digit. The code I have so far doesn't work but I feel like I'm close. Any help you can offer is appreciated.
System.out.println("Please enter a single character: "); String character = in.next(); System.out.println(character); if (character.isLetter()){ System.out.println("The character entered is a letter."); } else (character.isDigit()){ Syste.out.println("The character entered is a digit."); 
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Python String isdigit() The isdigit() method returns True if all characters in a string are digits.
isalnum() is a built-in Python function that checks whether all characters in a string are alphanumeric. In other words, isalnum() checks whether a string contains only letters or numbers or both. If all characters are alphanumeric, isalnum() returns the value True ; otherwise, the method returns the value False .
You can use the Character. isLetter(char c) method to check if a character is a valid letter. This method will return a true value for a valid letter characters and false if the character is not a valid letter.
You could use:
if (Character.isLetter(character.charAt(0))){ .... You could use the existing methods from the Character class. Take a look at the docs:
http://download.java.net/jdk7/archive/b123/docs/api/java/lang/Character.html#isDigit(char)
So, you could do something like this...
String character = in.next(); char c = character.charAt(0); ... if (Character.isDigit(c)) { ... } else if (Character.isLetter(c)) { ... } ... If you ever want to know exactly how this is implemented, you could always look at the Java source code.
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