在生活中，不可能一個類組成一個方法己肮，比如汽車壞了士袄，是需要送到修理廠的；電視機(jī)谎僻，電腦壞了窖剑，也是需要找一個器修廠的。Java中也是一樣的戈稿，一個類對應(yīng)的只是一項(xiàng)內(nèi)容西土，因此，Java中有時候會需要多個類來共同操作鞍盗。
下面的代碼就是多類使用的案例：代碼中涌動了有參構(gòu)造函數(shù)和無參構(gòu)造函數(shù)需了，
package qianfeng;
class DianNao1{//定義了一個電腦類
?String screen;
?String keyboard;//成員變量
?
?public DianNao1() {
??screen = null;
??keyboard = null;
?}//無參構(gòu)造方法跳昼，初始化變量
?
?public DianNao1(String s,String k) {
??screen = s;
??keyboard = k;
?}//有參構(gòu)造方法
?
?public void working() {
??if (screen != null) {
???System.out.println("電腦運(yùn)行正常");
??}else {
???System.out.println("電腦出現(xiàn)故障");
??}
?}
}
class DianShi{
?String screen;
?String controller;
public DianShi() {}
public DianShi(String s,String c) {
?screen = s;
?controller = c;
?}
public void watching() {
?if(controller !=null) {
??System.out.println("電視運(yùn)行正常");
?}else {
??System.out.println("電視出現(xiàn)故障");
??}
?}
}
class Factory{
?String name;
?String address;
?String telephone;
?
?public Factory(String n,String a,String t) {
??name = n;
??address = a;
??telephone = t;
?}
public void repairDianShi(DianShi ds) {
?
?if(ds.controller == null) {
??System.out.println("電視已修好");
??ds.controller = "null";
??}else {
???System.out.println("電視并沒有問題");
??}
?}
public void repairDianNao1(DianNao1 dn) {
?
?if (dn.screen == null) {
??System.out.println("電腦已修好");
??dn.screen = "null";
?}else {
??System.out.println("電腦沒有問題");
?}
}
}
public class DianNao {
?
?public static void main(String[] args) {
??
??DianNao1 dell = new DianNao1("AOC", "雙飛燕");
??DianShi mi = new DianShi("SHAPP", "Apple");
??Factory f= new Factory("磊哥電器維修十年老店", "迪拜塔頂層", "88888888");
??
???for(int i = 0;i < 5; i ++) {
????dell.working();
???}
???
???dell.screen = null;
???dell.working();
???
???f.repairDianNao1(dell);
???dell.working();
???
???for (int i = 0; i <5; i ++) {
????mi.watching();
???}
???
???mi.controller = null;
???mi.watching();
???
???f.repairDianShi(mi);
???mi.watching();
?}
??
}
