//With these I am getting compilation - error class not found
/*import Shape.TwoD.*;
import Shape.ThreeD.*;
import Shape.*;*/
import Shape.TwoD.Circle;
import Shape.TwoD.Line;
import Shape.ThreeD.Line3D;
import Shape.ThreeD.Sphere;
import Shape.Actions;
public class Test {
/**
* Creates a new instance of <code>Test</code>.
*/
int o;
public Test() {
}
/**
* @param args the command line arguments
*/
public static void main(String[] args) {
// TODO code application logic here
Actions obj[] = new Actions[4];
obj[0] = new Line(1,2,3,4);
obj[1] = new Circle(1,2,3);
obj[2] = new Line3D(1,2,3,4,5,6);
obj[3] = new Sphere(1,2,3,4);
for(Actions x: obj)
x.draw();
Actions.TwoD o =(Circle)obj[1];
System.out.println("Area of circle "+o.area());
o = (Sphere)obj[3];
System.out.println("Volume of sphere "+o.area());
}
}
Action是一个包含嵌套接口TwoD和ThreeD
为什么导入通配符不能在上面的代码中工作？我使用它错了吗？
我找不到任何相关的答案，如果通配符和完全限定的导入都不起作用，那么我的代码就会出现问题，但在这种情况下，只有当我使用带通配符的通配符时才会出现编译错误class not found。
编辑：
抱歉错误的命名约定，Line，Circle，Line3D和Sphere是类
Line和Circle位于Shape.TwoD
Line3D和Sphere位于Shape.ThreeD
Actions.java：
包形状;
public interface Actions {
interface ThreeD{
double volume();
}
interface TwoD{
double area();
}
void draw();
//void erase();
final double pi = 3.142857;
}
Line.java：
package Shape.TwoD;
public class Line implements Shape.Actions{
BaseObj.Point p1,p2;
public Line(int x1,int y1, int x2 ,int y2) {
p1 = new BaseObj.Point(x1,y1);
p2 = new BaseObj.Point(x2,y2);
}
public void draw(){
//System.out.println("Line between ("+p1.x+","+p1.y+") and ("+p2.x+","+p2.y+"));
System.out.println("Line between ("+p1.getx()+","+p1.gety()+") and ("+p2.getx()+","+p2.gety()+") has been drawn");
}
}
Circle.java：
package Shape.TwoD;
public class Circle extends BaseObj.Point implements Shape.Actions, Shape.Actions.TwoD{
protected int radius;
public Circle(int x, int y, int radius) {
super(x,y);
this.radius = radius;
}
public void draw(){
System.out.println("Circle with ("+x+","+y+") as center and radius "+radius+" units has been drawn");
}
public double area(){
return (pi*radius*radius);
}
}
Line3D.java：
package Shape.ThreeD;
public class Line3D implements Shape.Actions {
BaseObj.Point3D p1,p2;
public Line3D(int x1,int y1, int z1, int x2,int y2, int z2) {
p1 = new BaseObj.Point3D(x1,y1,z1);
p2 = new BaseObj.Point3D(x2,y2,z2);
}
public void draw(){
//System.out.println("Line between ("+p1.x+","+p1.y+") and ("+p2.x+","+p2.y+"));
System.out.println("Line between ("+p1.getx()+","+p1.gety()+","+p1.getz()+") and ("+p2.getx()+","+p2.gety()+","+p2.getz()+") has been drawn");
}
}
Sphere.java：
package Shape.ThreeD;
public class Sphere extends Shape.TwoD.Circle{
int z;
public Sphere(int x, int y, int z, int radius) {
super(x,y,radius);
this.z = z;
}
public void draw(){
System.out.println("Spere with ("+x+","+y+","+z+") as center and radius "+radius+" units has been drawn");
}
public double volume(){
return(radius*radius*pi*4/3);
}
public double area(){
System.out.println("Sphere is a 3D object so 2D quantitys doesnt apply");
return 0.0;
}
}
EDIT2：
在更正名称后，我收到Actions接口重复的错误，因此我将其名称更改为ObjActions并解决了问题。谢谢您的帮助。我希望我在下面使用的命名约定符合标准。
ObjActions.java
package shape;
public interface ObjActions {
interface Actions3D{
double volume();
}
interface Actions2D{
double area();
}
void draw();
//void erase();
final double pi = 3.142857;
}
Circle.java
package shape.twod;
public class Circle extends baseobj.Point implements shape.ObjActions, shape.ObjActions.Actions2D{
protected int radius;
public Circle(int x, int y, int radius) {
super(x,y);
this.radius = radius;
}
public void draw(){
System.out.println("Circle with ("+x+","+y+") as center and radius "+radius+" units has been drawn");
}
public double area(){
return (pi*radius*radius);
}
}
Line.java
package shape.twod;
public class Line implements shape.ObjActions{
baseobj.Point p1,p2;
public Line(int x1,int y1, int x2 ,int y2) {
p1 = new baseobj.Point(x1,y1);
p2 = new baseobj.Point(x2,y2);
}
public void draw(){
//System.out.println("Line between ("+p1.x+","+p1.y+") and ("+p2.x+","+p2.y+"));
System.out.println("Line between ("+p1.getx()+","+p1.gety()+") and ("+p2.getx()+","+p2.gety()+") has been drawn");
}
}
Line3D.java
package shape.threed;
public class Line3D implements shape.ObjActions {
baseobj.Point3D p1,p2;
public Line3D(int x1,int y1, int z1, int x2,int y2, int z2) {
p1 = new baseobj.Point3D(x1,y1,z1);
p2 = new baseobj.Point3D(x2,y2,z2);
}
public void draw(){
//System.out.println("Line between ("+p1.x+","+p1.y+") and ("+p2.x+","+p2.y+"));
System.out.println("Line between ("+p1.getx()+","+p1.gety()+","+p1.getz()+") and ("+p2.getx()+","+p2.gety()+","+p2.getz()+") has been drawn");
}
}
Sphere.java
package shape.threed;
public class Sphere extends shape.twod.Circle implements shape.ObjActions.Actions3D{
int z;
public Sphere(int x, int y, int z, int radius) {
super(x,y,radius);
this.z = z;
}
public void draw(){
System.out.println("Spere with ("+x+","+y+","+z+") as center and radius "+radius+" units has been drawn");
}
public double volume(){
return(radius*radius*pi*4/3);
}
}
Test.java
package test;
import shape.twod.*;
import shape.threed.*;
import shape.*;
/*import shape.twod.Circle;
import shape.twod.Line;
import shape.threed.Line3D;
import shape.threed.Sphere;
import shape.Actions;*/
public class Test {
/**
* Creates a new instance of <code>Test</code>.
*/
int o;
public Test() {
}
/**
* @param args the command line arguments
*/
public static void main(String[] args) {
// TODO code application logic here
ObjActions obj[] = new ObjActions[4];
obj[0] = new Line(1,2,3,4);
obj[1] = new Circle(1,2,3);
obj[2] = new Line3D(1,2,3,4,5,6);
obj[3] = new Sphere(1,2,3,4);
for(ObjActions x: obj)
x.draw();
ObjActions.Actions2D o =(Circle)obj[1];
//Actions2D o =(Circle)obj[1];
System.out.println("Area of circle "+o.area());
ObjActions.Actions3D op = (Sphere)obj[3];
System.out.println("Volume of sphere "+op.volume());
}
}
答案 0 :(得分：0)
＆＃34;包＆＃34;根据{{3}}，TwoD和ThreeD可能会被接口Action.TwoD和Action.ThreeD（反之亦然）遮蔽：
声明可能被简单名称为Vector的类型的单一类型导入声明遮蔽;通过名为Vector的类型并在编译单元所属的包中声明;或任何嵌套的类或接口。
声明可能会被名为Vector的字段，参数或局部变量的声明所掩盖。
（任何这些情况都会发生。）