Java - Double valueOf(String) method



Description

The Java Double valueOf(String s) method returns a Double object holding the double value represented by the argument string s.If s is null, then a NullPointerException is thrown.

Declaration

Following is the declaration for java.lang.Double.valueOf() method

public static Double valueOf(String s) throws NumberFormatException

Parameters

s − This is the string to be parsed.

Return Value

This method returns a Double object holding the value represented by the String argument.

Exception

NumberFormatException − if the string does not contain a parsable number.

Example 1

The following example shows the usage of Double valueOf(String) method to get a Double object from a String. We've created a String with a valid double value and then using valueOf() method, we're retrieving the Double object and printing it.

package com.tutorialspoint;
public class DoubleDemo {
   public static void main(String[] args) {

      // returns the double value represented by the string argument
      String str = "50";
      Double retval = Double.valueOf(str);
      System.out.println("Value = " + retval);
   }
}  

Output

Let us compile and run the above program, this will produce the following result −

Value = 50.0

Example 2

The following example shows the usage of Double valueOf(String) method to get a Double object from a String. We've created a String with an invalid double value and then using valueOf() method, we're trying to retrieve the Double object and printing it. Program throws an exception as expected.

package com.tutorialspoint;
public class DoubleDemo {
   public static void main(String[] args) {

      // returns the double value represented by the string argument
      String str = "abc";
      Double retval = Double.valueOf(str);
      System.out.println("Value = " + retval);
   }
}  

Output

Let us compile and run the above program, this will produce the following result −

Exception in thread "main" java.lang.NumberFormatException: For input string: "abc"
	at sun.misc.FloatingDecimal.readJavaFormatString(Unknown Source)
	at sun.misc.FloatingDecimal.parseDouble(Unknown Source)
	at java.lang.Double.parseDouble(Unknown Source)
	at java.lang.Double.valueOf(Unknown Source)
	at com.tutorialspoint.DoubleDemo.main(DoubleDemo.java:9)

Example 3

The following example shows the usage of Double valueOf(String) method to get a Double object from a String. We've created a String with a valid negative double value and then using valueOf() method, we're retrieving the Double object and printing it.

package com.tutorialspoint;
public class DoubleDemo {
   public static void main(String[] args) {

      // returns the double value represented by the string argument
      String str = "-50";
      Double retval = Double.valueOf(str);
      System.out.println("Value = " + retval);
   }
}  

Output

Let us compile and run the above program, this will produce the following result −

Value = -50.0
java_lang_double.htm
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