Check a character in a String is number or not in Java

 

All you need is this simple function in java.lang package.

Character.isDigit(c)

Of course, if want to check a character in a string, need to get the char first by using the following.

str.charAt(i)

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Category >> Basics  
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  • Apurv Dubey

    this is about character in a string and not whole string. For ex: “`Character.isDigit(“hello1world”.charAt(5))“` returns true

  • Abdul Shameer

    It could be easy to do as follows:


    public boolean isStringDigit(String str){
    try{
    Integer.valueOf(str);
    }catch(NumberFormatException ne){
    System.out.println("In NFE ");return false;
    }
    return true;
    }