使用ant脚本编译库

Question

I created package (project) Point , which contains classes Square , Rectangle , Point , Circle and Line . They are simple classes with constructors for creating said objects. From main in Point, you call them like this:

Point p1 = new Point(0,3);

I should write a program, that asks user to select which object he wants to create and set its geometry and i can only use my Point package as a library.

1) create the simple-graphics.jar library. I removed main method in my Point package and managed to produce simple-graphics.jar executable .jar file from my Point package.

2) I am asked to create some ant script that compiles this library from its source files and generates .jar file, however, i have no clue how to do that and if i havent already done it in 1), tutorials on ant scripts are not very clear to me. I guess im supposed to do it both ways, by selecting produce .jar option in NetBeans and by having somewhere this ant script.

3) I should be able to run .jar file generated by 2) by using java -jar simple-graphics.jar How do i do that in NetBeans, or should i use cmd? Im on W7.

EDIT: Thank you for the script, as a look at it i definitely wouldnt be able to write all of that.

How do i use this library in my program? SOLVED - like this:

package simpleapp;

import point;

public class SimpleApp{



  public static void main(String [] args){


     //Please press 1 to create Point
     //Please specify x and y axis:
     //i will select the type of object and create it
     //Object o = new whichObject(1)(x,y); 

  }
}

Point class in package Point, other classes are very similar:

package point;

public class Point{

 double x;
 double y;

 public Point(double a, double b){
  x = a;
  y = b;
 }

 public Point(){
  x = 0;
  y = 0;
 }

 public double distance(Point p){
   return Math.sqrt((p.x - x) * (p.x - x) + (p.y - y) * (p.y-y));
 }
}

Answer 1

Here is a very basic Ant script ( build.xml ) to compile your Java files to class files and pack them into a JAR file assuming your Java source files are in subdirectory src . Be aware that this is only a starting point.

<project name="Point-Library" default="build">

  <property name="src.dir" value="src" />
  <property name="build.dir" value="build" />
  <property name="jar.name" value="simple-graphics.jar" />

  <target name="build" depends="prepare, compile, jar" />

  <target name="prepare" description="Creates the build folder">
    <mkdir dir="${build.dir}" />
  </target>

  <target name="compile" description="Compiles the Java source files">
    <javac srcdir="${src.dir}" destdir="${build.dir}" />
  </target>

  <target name="jar" description="Packs the compiled Java classes into a JAR file">
    <jar basedir="${build.dir}" destfile="${jar.name}" />
  </target>

</project>

But you should first read the offical Ant manual to understand the concepts.

To use the resulting JAR file you have to add it to your classpath (which you did already). Then you can import the package point .

package simpleapp;

import point; // <---

public class SimpleApp{



  public static void main(String [] args){


     //Please press 1 to create Point
     //Please specify x and y axis:
     //i will select the type of object and create it
     //Object o = new whichObject(1)(x,y); 

  }
}

It makes no difference for your client code which uses the point classes whether their source code is part of your project or you import only the JAR file containing the point class files.