package java.nio.file does not exist

Question

I'm working out how to compile java from command line at the moment. Here's what I've got:

Here's what I've got:

/myjava/compile.cmd
/myjava/src/a_pack/HelloWorld.java
/myjava/src/b_pack/Inner.java
/myjava/src/b_pack/Inner2.java
/myjava/bin

HelloWorld:

package a_pack;

import b_pack.Inner;
import b_back.Inner2;
import java.util.ArrayList; 
import java.util.Iterator; 

public class HelloWorld {

    public static void main(String[] args) {

        System.out.println("Hello, World");     

        Inner myInner = new Inner(); 
        myInner.myInner(); 

        Inner2 myInner2 = new Inner2();
        myInner2.myInner(); 


        ArrayList myArray = new ArrayList(); 
        myArray.add(1); 
        myArray.add(2); 
        myArray.add(3); 

        Iterator itr = myArray.iterator();
        while (itr.hasNext())
        {
            System.out.println(itr.next()); 
        }

    }

}

Inner.java

package b_pack; 

public class Inner {

    public void myInner() {
        System.out.println("Inner Method");
    }

}

Inner2.java

package b_pack; 

public class Inner2 {

    public void myInner() {
        System.out.println("SecondInner");
    }

}

I'm compiling this with javac -d bin -sourcepath -src src/a_pack/HelloWorld.java and this works fine.

Now my understanding is, that because the HelloWorld.java references the other packages in it's import statements, then javac goes and compiles those. And I'm guessing that for all the java packages, javac has them internally or something.

Anyway - if I add the following import line to HelloWorld.java

import java.nio.file.Files;

it fails with


D:\.....\myjava>javac -d bin -sourcepath src src/a_pack/HelloWo
rld.java
src\a_pack\HelloWorld.java:8: package java.nio.file does not exist
import java.nio.file.Files;
                    ^
1 error

What's the story here? Why are some java packages good and some not?

NIO was introduced in Java 7. What version of Java are using? — Reimeus
@Reimeus The JDK I'm using that contains javac is jdk1.6.0_32. — dwjohnston
@Reimeus Just a clarification for JDK vs JRE. The javac I'm using belongs to JDK1.6.0, and I'm explicitly defining the location of the javac.exe. But the version of java (using java -version on my computer is 1.7.0_07. So is the reason it fails because packages aren't in the JDK? — dwjohnston
Only if you use any of the new classes or syntax introduced in Java 7... — Reimeus

Reimeus Reimeus · Accepted Answer · 2013-05-16T03:38:34

Java NIO was introduced in Java 7. Compilers from earlier versions of the JDK will baulk at any code that contains these NIO classes. You need to upgrade to JDK 7 or higher.

package java.nio.file does not exist

4 Answers