Java “如何修复”;标记摘要上的语法错误;错误?
给定以下代码:Java “如何修复”;标记摘要上的语法错误;错误?,java,compiler-errors,abstract,Java,Compiler Errors,Abstract,给定以下代码: package core; public abstract class GeometricElement { private float area; public abstract void calculateArea( ); //will be implemented in subclasses public float getArea( ) { this.calculateArea( ); ret
package core;
public abstract class GeometricElement {
private float area;
public abstract void calculateArea( ); //will be implemented in subclasses
public float getArea( )
{
this.calculateArea( );
return area;
}
}
package core;
public class abstract PerfectPolygon extends GeometricElement
{
public abstract void calculateArea( );
private float length;
private int sides;
public float getRadius() { return this.length; }
public float getSides() { return this.sides; }
public void setRadius(float newLength) {this.length = newLength;}
public void setSides(float newSides) {this.length = newSides;}
}
package core;
public class PerfectTriangle extends PerfectPolygon {
PerfectTriangle() {}
public void calculateArea( ) { }
}
package core;
public class Square extends PerfectPolygon {
Square() {}
public void calculateArea( ) {}
}
包芯
public class Circle extends GeometricElement
{
private float radius;
Circle() {}
public float getRadius() { return this.radius; }
public void setRadius(float newRadius) {this.radius = newRadius;}
public void calculateArea( ) {}
}
我正处于项目的开始阶段,但是,我似乎无法继续,因为Eclipse抛出了以下错误:
1) 标记“抽象”上的语法错误,请删除类中的“此标记”
2) 类Square中的“PerfectPolygon无法解析为类型”
3) PerfectTriangle类中的“PerfectPolygon无法解析为类型”
请注意,我几乎没有编写代码,我刚刚开始编写代码,但是
出于某种原因,Eclipse不允许编译这段代码。
知道为什么吗?
谢谢你的帮助
问候,,
Ron课程内容应为:
public abstract class PerfectPolygon extends GeometricElement { ...
就像您的另一个抽象类一样,它可以编译
abstract class
而不是
class abstract
@请尝试以下方法: