To Double 

Apache Commons Lang 3.0 is a java library with lot of utilities and reusable components. This requires the library commons-lang3-3.0.1.jar to be in classpath. The following example shows using NumberUtils.toDouble() API. It converts the string to double. If the conversion fails, it returns 0.0d.

File Name  :   com/bethecoder/tutorials/commons_lang/tests/numbers/ToDoubleTest.java  Author  :   Sudhakar KV Email  :   [email protected]

package com.bethecoder.tutorials.commons_lang.tests.numbers; import org.apache.commons.lang3.math.NumberUtils; public class ToDoubleTest {   /**    * @param args    */   public static void main(String[] args) {     //NumberUtils.toDouble(String str)     System.out.println(NumberUtils.toDouble(null));     System.out.println(NumberUtils.toDouble(""));     System.out.println(NumberUtils.toDouble("12.34"));     //NumberUtils.toDouble(String str, double defaultValue)     System.out.println(NumberUtils.toDouble(null, 6.4));     System.out.println(NumberUtils.toDouble("", 6.4));     System.out.println(NumberUtils.toDouble("12.34", 6.4));   } }

0.0
0.0
12.34

6.4
6.4
12.34