代理模式-动态代理

ゝ一纸荒年。 2022-07-16 16:15 271阅读 0赞

package M_Proxy.dynamic;
    
    import java.lang.reflect.Proxy;
    
    /**
     *使用动态代理完成保护代理
     *
     */
    public class MatchMakingTestDrive {
        
    	
    	public static void main(String[] args) {
        
    		MatchMakingTestDrive test = new MatchMakingTestDrive();
    		test.drive();
    	}
    
    	private void drive() {
        
    		// 创建对象
    		PersonBean personBean = new PersonBeanImpl("张三", "女", "兴趣是上网", 10);
    		// 创建拥有者对象
    		PersonBean ownerProxy = getOwnerProxy(personBean);
    		System.out.println(ownerProxy.getName());
    		// 行得通
    		ownerProxy.setInterests("bowling go");
    		System.out.println(ownerProxy.getInterests());
    		// 改变评分，行不通
    		try {
        
    			ownerProxy.setHotOrNotRating(10);
    		} catch (Exception e) {
        
    			System.out.println("修改评分失败");
    		}
    
    		System.out.println("============");
    		// 创建非拥有者对象
    		PersonBean nonOwnerProxy = getNonOwnerProxy(personBean);
    		// 失败
    		try {
        
    			nonOwnerProxy.setInterests("哈哈");
    		} catch (Exception e) {
        
    			System.out.println("设置兴趣爱好失败");
    		}
    		// 成功
    		nonOwnerProxy.setHotOrNotRating(8);
    		System.out.println(nonOwnerProxy.getHotOrNotRating());
    
    	}
    
    	private PersonBean getNonOwnerProxy(PersonBean person) {
        
    		return (PersonBean) Proxy.newProxyInstance(person.getClass()
    				.getClassLoader(), person.getClass().getInterfaces(),
    				new NonOwnerInvocationHandler(person));
    	}
    
    	public PersonBean getOwnerProxy(PersonBean person) {
        
    		return (PersonBean) Proxy.newProxyInstance(person.getClass()
    				.getClassLoader(), person.getClass().getInterfaces(),
    				new OwnerInvocationHandler(person));
    	}
    }

package M_Proxy.dynamic;
    
    import java.lang.reflect.InvocationHandler;
    import java.lang.reflect.InvocationTargetException;
    import java.lang.reflect.Method;
    
    /**
     * 非拥有者对象
     */
    public class NonOwnerInvocationHandler implements InvocationHandler {
        
    
    	PersonBean person;
    
    	public NonOwnerInvocationHandler(PersonBean person) {
        
    		this.person = person;
    	}
    
    	public Object invoke(Object proxy, Method method, Object[] args)
    			throws IllegalAccessException {
        
    		try {
        
    			if (method.getName().startsWith("get")) {
        
    				return method.invoke(person, args);
    			} else if (method.getName().startsWith("setHotOrNotRating")) {
        
    				return method.invoke(person, args);
    			} else if (method.getName().startsWith("set")) {
        
    				throw new IllegalAccessException();
    			}
    		} catch (InvocationTargetException e) {
        
    			e.printStackTrace();
    		}
    		return null;
    	}
    
    }

package M_Proxy.dynamic;
    
    import java.lang.reflect.InvocationHandler;
    import java.lang.reflect.InvocationTargetException;
    import java.lang.reflect.Method;
    
    /**
     * 真正拥有者对象
     */
    public class OwnerInvocationHandler implements InvocationHandler {
        
    
    	PersonBean person;
    
    	public OwnerInvocationHandler(PersonBean person) {
        
    		this.person = person;
    	}
    
    	public Object invoke(Object proxy, Method method, Object[] args)
    			throws IllegalAccessException {
        
    		try {
        
    			if (method.getName().startsWith("get")) {
        
    				return method.invoke(person, args);
    			} else if (method.getName().startsWith("setHotOrNotRating")) {
        
    				throw new IllegalAccessException();
    			} else if (method.getName().startsWith("set")) {
        
    				return method.invoke(person, args);
    			}
    		} catch (InvocationTargetException e) {
        
    			e.printStackTrace();
    		}
    
    		return null;
    	}
    
    }

package M_Proxy.dynamic;
    
    public class PersonBeanImpl implements PersonBean {
        
    	String name;
    	String gender;
    	String interests;
    	int rating;
    	int ratingCount = 0;
    
    	public PersonBeanImpl(String name, String gender, String interests,
    			int rating) {
        
    		this.name = name;
    		this.gender = gender;
    		this.interests = interests;
    		this.rating = rating;
    		ratingCount++;
    	}
    
    	public String getName() {
        
    		return name;
    	}
    
    	public String getGender() {
        
    
    		return gender;
    	}
    
    	public String getInterests() {
        
    
    		return interests;
    	}
    
    	public int getHotOrNotRating() {
        
    		return ratingCount == 0 ? 0 : rating / ratingCount;
    	}
    
    	public void setName(String name) {
        
    		this.name = name;
    	}
    
    	public void setGender(String gender) {
        
    		this.gender = gender;
    	}
    
    	public void setInterests(String interests) {
        
    		this.interests = interests;
    	}
    
    	public void setHotOrNotRating(int rating) {
        
    		this.rating += rating;
    		ratingCount++;
    	}
    
    }

package M_Proxy.dynamic;
    
    public interface PersonBean {
        
    	String getName();
    
    	String getGender();
    
    	String getInterests();
    
    	int getHotOrNotRating();
    
    	void setName(String name);
    
    	void setGender(String gender);
    
    	void setInterests(String interests);
    
    	void setHotOrNotRating(int rating);
    }