第七周Java作业

–在包bzu.aa中定义一个交通工具类（Vehicle）： 
属性——载客量（capacity） 
方法 
无参构造方法（给capacity初始化值为2，并输出“执行交通工具类的无参构造方法。”） 
有参构造方法（传参给capacity初始化，并输出“执行交通工具的有参构造方法。”） 
capacity的set、get方法 
print方法：输出capacity 
–在包bzu.aa中定义一个汽车类（Car）继承交通工具类： 
属性——speed 
方法 
无参构造方法（给speed初始化值为0，并输出“执行汽车类的无参构造方法。”） 
有参构造方法（用super关键字调用父类的有参构造方法，传参给speed初始化，并输出“执行汽车类的有参构造方法。”） 
加速（speedup）：speed+10并返回speed； 
减速（speeddown）：speed-15并返回speed； 
重写print方法：输出speed和capacity。 
–在包bzu.bb中定义一个final的公交车类（Bus），继承汽车类： 
属性——载客量（capacity）<变量隐藏> 
方法 
无参构造方法（给capacity初始化值为20，并输出“执行公交车类的无参构造方法。”） 
有参构造方法（用super关键字调用父类的有参构造方法，传参给capacity初始化，并输出“执行公交车类的有参构造方法。”） 
重写print方法：输出speed、 capacity及父类的capacity。 
–在包bzu.bb中编写一个主类Test： 
主函数 
调用无参构造方法创建一个Car的对象car；调用加速方法将速度加至50，调用print方法；调用减速方法，将速度减至20，调用print方法。 
调用有参构造方法创建一个Bus的对象bus；调用print方法。

OC：Bus定义capacity覆盖父类变量的时候会提示重复定义，改为了_capacity,文件中的capacity来自父类。 
Vehicle.h文件

////  Vehicle.h////  Created by Zb_tjw on 2017/10/11.//  Copyright © 2017年 Zb_tjw. All rights reserved.//#import <Foundation/Foundation.h>@interface Vehicle : NSObject{    int capacity;}-(id) init;-(instancetype) initWithCapacity:(int)newCapacity;-(void) setCapacity:(int)newCapacity;-(int) capacity;-(void) print;@end
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Vehicle.m文件

////  Vehicle.m////  Created by Zb_tjw on 2017/10/11.//  Copyright © 2017年 Zb_tjw. All rights reserved.//#import "Vehicle.h"@implementation Vehicle-(id) init{    if(self = [super init]){        NSLog(@"执行交通工具类的无参构造方法");    }    return self;}-(instancetype) initWithCapacity:(int)newCapacity{    self = [super init];    if (self) {        capacity = newCapacity;        NSLog(@"执行交通工具的有参构造方法");    }    return self;}-(void) setCapacity:(int)newCapacity{    capacity = newCapacity;}-(int) capacity{    return capacity;}-(void) print{    NSLog(@"capacity=%d",capacity);}@end
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Car.h文件

////  Car.h////  Created by Zb_tjw on 2017/10/11.//  Copyright © 2017年 Zb_tjw. All rights reserved.//#import "Vehicle.h"@interface Car : Vehicle{    int speed;}-(id) init;-(instancetype) initWithSpeed:(int)newSpeed andCapacity:(int)newCapacity;-(NSString *) speedUp;-(NSString *) speedDown;-(int) speed;@end
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Car.m文件

////  Car.m////  Created by Zb_tjw on 2017/10/11.//  Copyright © 2017年 Zb_tjw. All rights reserved.//#import "Car.h"@implementation Car-(id) init{    if (self = [super init]) {        speed = 0;        NSLog(@"执行汽车类的无参构造方法");    }    return self;}-(instancetype) initWithSpeed:(int)newSpeed andCapacity:(int)newCapacity{    if (self = [super initWithCapacity:newCapacity]) {        speed = newSpeed;        NSLog(@"执行汽车类的有参构造方法");    }    return self;}-(NSString *) speedUp{    speed += 10;    //字符串拼接    NSString *newString = [NSString stringWithFormat:@"当前速度=%d",speed];    return newString;}-(NSString *) speedDown{    speed -= 15;    //字符串拼接    NSString *newString = [NSString stringWithFormat:@"当前速度=%d",speed];    return newString;}-(int) speed{    return speed;}-(void) print{    NSLog(@"speed=%d,capacity=%d",speed,capacity);}@end
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Bus.h文件

////  Bus.h////  Created by Zb_tjw on 2017/10/11.//  Copyright © 2017年 Zb_tjw. All rights reserved.//#import "Car.h"const @interface Bus : Car{//    int capacity;//Duplicate member 'capacity'    int _capacity;}-(id) init;-(instancetype) initWithCapacity:(int)newCapacity;-(void) print;@end
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Bus.m文件

////  Bus.m////  Created by Zb_tjw on 2017/10/11.//  Copyright © 2017年 Zb_tjw. All rights reserved.//#import "Bus.h"@implementation Bus-(id) init{    if (self = [super init]) {        _capacity = 20;        NSLog(@"执行公交车类的无参构造方法");    }    return  self;}-(instancetype) initWithCapacity:(int)newCapacity{    if (self = [super initWithSpeed:200 andCapacity:25]) {        _capacity = newCapacity;        NSLog(@"执行公交车类的有参构造方法");    }    return self;}-(void) print{    NSLog(@"speed=%d,capacity=%d,_capacity=%d",speed,capacity,_capacity);}@end
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main.m文件

////  main.m////  Created by Zb_tjw on 2017/10/11.//  Copyright © 2017年 Zb_tjw. All rights reserved.//#import <Foundation/Foundation.h>#import "Vehicle.h"#import "Car.h"#import "Bus.h"int main(int argc, const char * argv[]) {    @autoreleasepool {        // insert code here...        Car *car = [[Car alloc] init];        while([car speed]!=50){            NSLog(@"%@",[car speedUp]);        }        while ([car speed]!=20) {            NSLog(@"%@",[car speedDown]);        }        Bus *bus = [[Bus alloc] initWithCapacity:25];        [bus print];    }    return 0;}
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运行截图: 

Java：还是老本行写着简单舒服，看起来也清晰 
首先包结构： 

Vehicle.java文件

package bzu.aa;public class Vehicle {    public int capacity;    public Vehicle() {        capacity = 2;        System.out.println("执行交通工具类的无参构造方法。");    }    public Vehicle(int capacity) {        this.capacity = capacity;        System.out.println("执行交通工具类的无参构造方法。");    }    public int getCapacity() {        return capacity;    }    public void setCapacity(int capacity) {        this.capacity = capacity;    }    public void print(){        System.out.println("capacity=="+capacity);    }}
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Car.java文件

package bzu.aa;public class Car extends Vehicle {    public int speed;    public Car() {        // TODO Auto-generated constructor stub        speed = 0;        System.out.println("执行汽车类的无参构造方法。");    }    public Car(int speed,int capacity) {        super(capacity);        this.speed = speed;        // TODO Auto-generated constructor stub        System.out.println("执行汽车类的有参构造方法。");    }    public void speedUp(){        speed += 10;        System.out.println("speed=="+speed);    }    public void speedDown(){        speed -= 15;        System.out.println("speed=="+speed);    }    public void print() {        // TODO Auto-generated method stub        System.out.print("speed=="+speed+"  ");        System.out.println("capacity=="+capacity);    }}
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Bus.java文件

package bzu.bb;import bzu.aa.Car;final class Bus extends Car {    int capacity;    public Bus() {        // TODO Auto-generated constructor stub        capacity = 20;        System.out.println("执行公交车类的无参构造方法。");    }    public Bus(int speed, int capacity) {        super(speed, capacity);        this.capacity = capacity;        System.out.println("执行公交车类的有参构造方法。");        // TODO Auto-generated constructor stub    }    public void print() {        // TODO Auto-generated method stub        System.out.println("speed=="+speed);        System.out.println("父类capacity=="+super.getCapacity());        System.out.println("子类capacity=="+capacity);        System.out.println("父类capacity=="+super.capacity);    }}
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Test.java文件

package bzu.bb;import bzu.aa.Car;public class Test {    /**     * @param args     */    public static void main(String[] args) {        // TODO Auto-generated method stub        Car car = new Car();        while (car.speed!=50) {            car.speedUp();        }        while (car.speed!=20) {            car.speedDown();        }        car.print();        Bus bus = new Bus(200,25);        bus.print();    }}
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运行截图: