Correctly Importing Apache Commons Math Package

问题

I am trying to use the SimplexSolver class in the Apache Commons Math package, but I can't seem to import the package correctly; all of the following is happening in a fixed directory called 'Java'. I downloaded commons-math3-3.1.1 and put the unzipped folder into the 'Java' directory.

Here is some example code, HelloWorld.java, saved in the 'Java' directory:

import org.apache.commons.math;

public class HelloWorld {
        public static void main (String[] args) {
                System.out.println("Hello World!");
                }
}

I then proceed to type the following command into the terminal:

javac -cp ./commons-math3-3.1.1/commons-math3-3.1.1.jar:. HelloWorld.java

And I am greeted with the following error:

HelloWorld.java:1: package org.apache.commons does not exist
import org.apache.commons.math;
                         ^
1 error

I'm sure I'm misunderstanding the correct way to import downloaded packages, and any help would be greatly appreciated. I've tried variants of the import line, such as import org.apache.commons.math.*; and things like that, but none of them have worked so far.

Thanks in advance!

回答1:

The correct package name is

org.apache.commons.math3.

来源：https://stackoverflow.com/questions/14429630/correctly-importing-apache-commons-math-package