Animals 父类：
public class Animals {
private String name;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
动物子类：
public class Dog extends Animals {
private String name;
public Dog(String dog) {
// TODO Auto-generated constructor stub
this.name = dog;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
测试类-从添加的信息中挑选出符合条件的信息：
package czx.test_extends;
public class TestAnimals {
public static void main(String[] args) {
Animals[] as = new Animals[] { new Dog("miaomiao") };
getAllDog(as);
for(int i=0;i<as.length;i++) {
if(as[i]==null) {
continue;
}else {
System.out.println(as[i].getName());
}
}
}
public static Dog[] getAllDog(Animals[] a) {
String num;
Dog[] dog = new Dog[a.length];
int s = 0;
for (int j = 0; j < a.length; j++) {
num = a.getClass().getCanonicalName();
if (num.equals("Dog")) {
dog[s] = (Dog) a[j];
s++;
}
}
return dog;
}
}