Java determines whether it is a decimal

java determines whether it is a decimal:

public class JudgeNumber {
     
   public static boolean judgeIsDecimal(String num){
         
        boolean isdecimal = false;
         
        if (num.contains(".")) {
             
             isdecimal=true;
              
        }
         
        return isdecimal;
         
    }
     
    public static void main(String[] args) {  //测试的main方法
         
        int num1 = 34;
         
        double num2=67.8;
         
        boolean is1 = judgeIsDecimal(String.valueOf(num1));
         
        boolean is2=judgeIsDecimal(String.valueOf(num2));
         
        System.out.println(is1);//fasle
         
        System.out.println(is2);//true
         
    }
     
}

Java String.contains() method, returns true if and only if this string contains the specified char value sequence .

The following is the declaration of the java.lang.String.contains() method

public boolean contains(CharSequence s)

Parameters:

s-- This is the sequence to search for.

Return value:

If this string contains, this method returns true, otherwise it returns false.

For more java knowledge, please pay attention to java basic tutorial.

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