JavaCompiler giving NullPointerException on "ToolProvider.getSystemJavaCompiler()". I'm pretty sure I have JDK set up right?

Question

The section of code in question is:

String fileToCompile = "C:/Users/Jeff/Documents/Test/Compiler 6/examplejavafile.java";//Absolute path
JavaCompiler compiler = ToolProvider.getSystemJavaCompiler();
FileOutputStream errorStream = new FileOutputStream("Errors.txt");
int compilationResult = compiler.run(null, null, errorStream, "-verbose", fileToCompile);
if(compilationResult == 0){
    System.out.println("Compilation is successful");
}else{
    System.out.println("Compilation Failed");
}

When I run this section of code it gives me NPE on:

JavaCompiler compiler = ToolProvider.getSystemJavaCompiler();

Now I've been told that this is an error in the environment, but I have JDK installed and my CLASSPATH variable is set to "C:\Program Files\Java\jdk1.7.0_04\bin". I might be a noob and not understand how to run a program through JDK instead of JRE, but regardless I need help. (Also, I am using Eclipse, if it's any different.)

How can _that_ line give a NPE? What does the stack trace look like? — Thorbjørn Ravn Andersen, Jun 05 '12 at 23:51

score 0 · Answer 1 · answered Jun 05 '12 at 23:58

0

Look up the Run Configuration for the project (under the Run menu). Under JRE is should specify the project execution environment is using 'JavaSE-1.6' (jsk1.6.20_32) or such.

answered Jun 05 '12 at 23:58

John D

2,307
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This makes sense, but the only options I see there say (jre7), which leads me to believe that I installed JDK wrong; Is there something I need to do to eclipse to update my installation? – Jeff Demanche Jun 06 '12 at 00:18

Akhilesh Dhar Dubey · Answer 2 · 2013-10-07T20:57:54.647

0

ToolProvider.getSystemJavaCompiler() is not available.

Is tools.jar missing from the classpath?

Set class path to the tools.jar file which can found in jdk\jre directory.

System.setProperty("java.home", "C:\\Program Files\\Java\\jdk1.7.0_02");

edited Oct 07 '13 at 20:57

answered Oct 07 '13 at 20:20

Akhilesh Dhar Dubey

2,152
2
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score -1 · Accepted Answer · answered Jun 05 '12 at 23:42

-1

You need to import the ToolProvider since it is not defined, unless you just didn't include that information.

import javax.tools.ToolProvider;

answered Jun 05 '12 at 23:42

richardhsu

878
5
13

Yes I have imported all the necessary tools. It's a console error on runtime. – Jeff Demanche Jun 05 '12 at 23:45
Hmm, I can't seem to see why that line would throw a NPE or even the line before it. I just ran the code and it seems to work fine on Ubuntu. Sorry :( – richardhsu Jun 05 '12 at 23:59
1

Please consider another [question](http://stackoverflow.com/questions/9403655/javacompiler-returning-null). In two words - if you are on Windows then check if JAVA_HOME points to JDK and not runtime environment. – Fedor Rusak Feb 13 '13 at 08:44

JavaCompiler giving NullPointerException on "ToolProvider.getSystemJavaCompiler()". I'm pretty sure I have JDK set up right?

3 Answers3