java的同志们来看看这段代码：

Question

  一直用的C#，最近有个项目用java,马马虎虎看了下java的基本入门书籍就开动了，但是以下代码中的DisplayPointsp()我认为应该是个class吧，java冒似不能嵌套定义class吧，也不能理解成方法吧，没有返回值呀，而且后面还用new来实例话了，是我火星了么？java的兄弟们来帮帮忙哈！这是我在网上下的配套的示例代码，应该不会有错哦：
import java.applet.Applet;
import java.awt.BorderLayout;
import com.sun.j3d.utils.applet.MainFrame;
import com.sun.j3d.utils.geometry.Primitive;
import com.sun.j3d.utils.universe.*;
import javax.media.j3d.*;
import javax.vecmath.*;
import com.sun.j3d.utils.behaviors.mouse.*;public class DisplayPointsp extends Applet
{
public BranchGroup createBranchGroupSceneGraph()
{
BranchGroup branchGroupRoot=new BranchGroup();
BoundingSphere bounds=new BoundingSphere(new Point3d(0.0,0.0,0.0),100.0);
Color3f bgColor=new Color3f(1.0f,1.0f,1.0f);
Background bg=new Background(bgColor);
bg.setApplicationBounds(bounds);
branchGroupRoot.addChild(bg);
Color3f directionalColor=new Color3f(1.0f,0.0f,0.0f);
Vector3f vec=new Vector3f(0.0f,0.0f,-1.0f);
DirectionalLight directionalLight=new DirectionalLight(directionalColor,vec);
directionalLight.setInfluencingBounds(bounds);
branchGroupRoot.addChild(directionalLight);

Appearance app=new Appearance();
Material material=new Material();
material.setDiffuseColor(new Color3f(1.0f,1.0f,0.0f));
app.setMaterial(material);
TransformGroup transformgroup=new TransformGroup();
transformgroup.setCapability(TransformGroup.ALLOW_TRANSFORM_READ);
transformgroup.setCapability(TransformGroup.ALLOW_TRANSFORM_WRITE);
branchGroupRoot.addChild(transformgroup);
MouseRotate mouserotate=new MouseRotate();
mouserotate.setTransformGroup(transformgroup);
branchGroupRoot.addChild(mouserotate);
mouserotate.setSchedulingBounds(bounds);
MouseZoom mousezoom=new MouseZoom();
mousezoom.setTransformGroup(transformgroup);
branchGroupRoot.addChild(mousezoom);
mousezoom.setSchedulingBounds(bounds);
MouseTranslate mousetranslate=new MouseTranslate();
mousetranslate.setTransformGroup(transformgroup);
branchGroupRoot.addChild(mousetranslate);
mousetranslate.setSchedulingBounds(bounds);

Shape3D shapepoints=new Shape3D();
float vertexes[]={
0.5f,0.5f,0.0f, -0.5f,0.5f,0.0f,
0.7f,0.0f,0.0f, -0.7f,0.0f,0.0f,
-0.5f,-0.5f,0.0f, 0.5f,-0.5f,0.0f,
0.0f,0.8f,0.0f, 0.0f,-0.8f,0.0f
};
float pointcolors[]={
1.0f,0.0f,0.0f, 0.0f,1.0f,0.0f,
0.0f,0.0f,1.0f, 1.0f,1.0f,0.0f,
0.0f,1.0f,1.0f, 1.0f,0.0f,1.0f,
0.0f,0.0f,0.0f, 0.0f,0.5f,1.0f
};
int vCount=8;
PointArray points=new PointArray(vCount,PointArray.COORDINATES|PointArray.COLOR_3);
points.setCoordinates(0,vertexes);
points.setColors(0,pointcolors);

PointAttributes pointsattributes=new PointAttributes();
pointsattributes.setPointSize(10.0f);
pointsattributes.setPointAntialiasingEnable(true);

Appearance app1=new Appearance();
app1.setPointAttributes(pointsattributes);

shapepoints.setGeometry(points);
shapepoints.setAppearance(app1);
transformgroup.addChild(shapepoints);
branchGroupRoot.compile();
return branchGroupRoot;
}
public DisplayPointsp()
{
this.setLayout(new BorderLayout());
Canvas3D c=new Canvas3D(SimpleUniverse.getPreferredConfiguration());
this.add(c,"Center");
SimpleUniverse u=new SimpleUniverse(c);
u.getViewingPlatform().setNominalViewingTransform();
u.addBranchGraph(this.createBranchGroupSceneGraph());
}
public static void main(String[] args)
{
new MainFrame(new DisplayPointsp(),300,300);
}
}

Answer 1

java冒似不能嵌套定义class吧，也不能理解成方法吧，Java中可以嵌套定义class的, 有两种嵌套的class, inner class, nested class(这两种到底哪一种是static的class我给忘了), 其实还有一种叫匿名class,你在C#中是怎么做的, 到Java中也怎么做, 基本上是一个样的.
微软抄得太没水平了, 搞得Java跟C#几乎一模一样.

Answer 2

那这段代码中DisplayPointsp怎么理解呢？？

Answer 3

劝你还是好好JAVA的基础篇吧 

Answer 4

你红色标记的那段是Constructor啊...难道C#的不是这么写么?

Answer 5

这个应该是一个public 的成员方法顺便提及 java中可以嵌套定义类 如Inhibitory所说 嵌套定义的类有很多让人头疼的语法但是主要分为这几种，内部类，静态内部类，方法内部类建议看一本比较权威的java入门教材 Java核心技术 和thinking in java 都不错

Answer 6

那，推荐给你个好书，去看看
<<java学习笔记>>很全的，从基础到高级开发

Answer 7

你那是構造器是在啟動的時候就加載的
class的話一定要有個class的前綴的
比如public class xxx（）
沒有public就class xxx（）也是個class
但一個java文件里面是不允許有2個public的class的
但可以有其他private的
====================
你還是基礎不熟悉，在去看下吧

Answer 8

public DisplayPointsp() 一个无参的构造方法，只要你new public DisplayPointsp() 就生成一个public DisplayPointsp实例

Answer 9

应该是C#更java 几乎一模一样。呵呵o(∩_∩)o...