1 class Cylinder { 2 private double radius; 3 private int height; 4 private double pi=3.14; 5 private String color; 6 public double setCylinder(double r,int h) { 7 radius=r; 8 height=h; 9 return r+h; 10 } 11 public void setCylinder(String str) { 12 color=str; 13 } 14 public void show() { 15 System.out.println("颜色为:"+color); 16 } 17 double area() { 18 return pi*radius*radius; 19 } 20 double volume() { 21 return area()*height; 22 } 23 } 24 public class C1_1 { 25 public static void main(String[] args) { 26 double r_h; 27 Cylinder volu=new Cylinder(); 28 r_h=volu.setCylinder(2.5,5); 29 volu.setCylinder("红色"); 30 System.out.println("半径和高之和="+r_h); 31 System.out.println("体积="+volu.volume()); 32 volu.show(); 33 } 34 }