Yes, Integer.parseInt() doesn't accept the empty string as a valid number. You
would have to initialise the strings to "0" as a default and then would be OK.I
think it is a bit of an opinion boundary case in that when I first discovered
it, I thought that the empty string should equate to 0, as both of them
represent the "zero / null" value. However, I suspect that it was done that way
as there is no Integer value that would translate back to the empty string for
consistency. I.e. what should String.valueOf(0) return, "0" or "". John
-------- Original message --------From: Zulfi Khan
<zulfi6...@yahoo.com.INVALID> Date: 04/05/2021 05:31 (GMT+00:00) To: NetBeans
Mailing List <users@netbeans.apache.org> Subject:
java.lang.NumberFormatException: For input string: "" Hi,I am getting following
message when I am compiling my program on NetBeans 12.3 on Ubuntu 18.04:cd
/home/zulfi/NetBeansProjects/GUI1; JAVA_HOME=/usr/lib/jvm/java-11-openjdk-amd64
/snap/netbeans/45/netbeans/java/maven/bin/mvn "-Dexec.args=-classpath
%classpath com.mycompany.gui1.GuiMain"
-Dexec.executable=/usr/lib/jvm/java-11-openjdk-amd64/bin/java process-classes
org.codehaus.mojo:exec-maven-plugin:3.0.0:execScanning for
projects...-------------------------< com.mycompany:GUI1
>-------------------------Building GUI1
1.0-SNAPSHOT--------------------------------[ jar
]------------------------------------ maven-resources-plugin:2.6:resources
(default-resources) @ GUI1 ---Using 'UTF-8' encoding to copy filtered
resources.skip non existing resourceDirectory
/home/zulfi/NetBeansProjects/GUI1/src/main/resources---
maven-compiler-plugin:3.1:compile (default-compile) @ GUI1 ---Changes detected
- recompiling the module!Compiling 1 source file to
/home/zulfi/NetBeansProjects/GUI1/target/classes---
exec-maven-plugin:3.0.0:exec (default-cli) @ GUI1
---java.lang.NumberFormatException: For input string: "" at
java.base/java.lang.NumberFormatException.forInputString(NumberFormatException.java:65)
at java.base/java.lang.Integer.parseInt(Integer.java:662) at
java.base/java.lang.Integer.parseInt(Integer.java:770) at
com.mycompany.gui1.GuiMain.main(GuiMain.java:21)------------------------------------------------------------------------BUILD
SUCCESS------------------------------------------------------------------------Total
time: 4.664 sFinished at:
2021-05-03T23:25:08-05:00---------------------------------------------My
program is given below:package com.mycompany.gui1;import javax.swing.*;import
java.lang.NumberFormatException;/** * * @author zulfi */public class GuiMain {
public static void main(String[] args){ final String strFirstNum="";
final String strSecNum=""; int val1=0; int val2=0; try{
val1 = Integer.parseInt(strSecNum); val2 =
Integer.parseInt(strFirstNum); }catch (NumberFormatException e) {
e.printStackTrace();} int res = val1 + val2;
JOptionPane.showMessageDialog(null, "Testing Sum = "+ res ); }
}Somebody please guide me.Zulfi.
