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5.8.5. Code exercise 5
Last updated: 27 January 2013.

Write a method named isDouble(String str) that returns true if the string argument can be parsed into a double value and false otherwise. If the string argument is null, the method returns false.


public final class Practice {

   
public boolean isDouble(String str){
         
if(str == null)
               
return false;

         
try{
               
Double.parseDouble(str);
               
return true;
         
}
         
catch(NumberFormatException e){
               
return false;
         
}
    }

}


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