课堂作业

第一题：

package student;

class Person {
private
int weight ;
private String name ;
private int age ;
public void setName (String myName) {
name = myName; }
public void setAge(int myAge) {
if (myAge <= 0) {
System.out.println ("年龄出错，使用默认年龄18岁代替") ;
age=18 ;}
else
age=myAge ;
}
public void setWeight (int myWeight) {
if (myWeight <= 0) {
System.out.println("体重出错，使用默认100斤代替") ;
weight = 100; }
else
weight = myWeight; }
public String getName () {
return name ;}
public int getAge() {
return age; }
public int getWeight () {
return weight ;}
public void talk () {
System. out.println (" 我是 :"+name+",今年:"+age+" 岁") ;}
public void dining () {
System.out.println("还没有吃饭，饿了.."+"体重:"+weight) ;
setWeight (weight++) ;
System.out.println ("吃饱了..."+",体重:"+weight) ;}
public void walk () {
setWeight (weight-2) ;
System.out.println("走累了..."+",体重:"+weight) ;}

}

public class Main {
public static void main (String [] args) {
Person p1= new Person () ;
p1.setName ("邓雪芳") ;
p1.setAge (-10) ;
p1.setWeight (90) ;
p1.talk() ;
p1.dining() ;
p1.walk () ;
p1.walk () ;
}
}

第二题：

package student;

class Student {
private int count ;
public void setCount (int myCount) {
if (myCount<0 && myCount>10)
System.out.println(" 获取错误");
else
count=myCount;
}
public int getCount() { 
if(count<=0) {
System.out.println(" 获取错误");
return 0;
}else{
return count;
}
}

}

public class TestStudent {
public static void main(String args[]){
Student s=new Student () ;
s.setCount(11) ;
s.setCount(5);
int count=s.getCount () ;
System.out.println("Count 的值是:"+count);
s.setCount (0) ;
count=s.getCount () ;
System.out.println("Count 的值是:"+count);
}

}package student;

class Student {
private int count ;
public void setCount (int myCount) {
if (myCount<0 && myCount>10)
System.out.println(" 获取错误");
else
count=myCount;
}
public int getCount() { 
if(count<=0) {
System.out.println(" 获取错误");
return 0;
}else{
return count;
}
}

}

public class TestStudent {
public static void main(String args[]){
Student s=new Student () ;
s.setCount(11) ;
s.setCount(5);
int count=s.getCount () ;
System.out.println("Count 的值是:"+count);
s.setCount (0) ;
count=s.getCount () ;
System.out.println("Count 的值是:"+count);
}

}

第三题：

package student;

public class StaticTest {
int x=0;
static int y=0;
StaticTest(int z){
x=z;
}
public static void main(String args[ ]) {
StaticTest s1=new StaticTest(1);
StaticTest s2=new StaticTest(2);
System.out.println("s1.x="+s1.x);
System.out.println("s2.x=”+s2.x");
System.out.println("s1.y=”+s1.y");
System.out.println("s2.y=”+s2.y");
s1.x++;
System.out.println( "改变x 的 值");
System.out.println("s1.x="+s1.x);
System.out.println("s2.x="+s2.x);
s1.y++;
System.out.println(" 通过s1 改变y的 值为："+s1.y);
System.out.println("s2 的y的 值为："+s2.y);
}

}

第四题：

public class Student {
int id=0;
static int studentNum=0;
Student(int x) {
id=x;
studentNum++;
}
public static void main(String args[ ]) {
Student s1=new Student(1000);
Student s2=new Student(1001);
Student s3=new Student(1002);
Student s4=new Student(1003);
System.out.println("s1 的学号："+s1.id);
System.out.println("s2 的学号："+s2.id);
System.out.println("s3 的学号："+s3.id);
System.out.println("s4 的学号："+s4.id);
System.out.println("学生的数目："+ Student.studentNum);
}
}