设计模式第一次作业

1.用户可以根据要求动态选择日志记录方式。使用Factory模式来设计；如果系统中增加一个日志记录方式—控制台日志记录（ConsoleLog），类图将如何改变？

抽象工厂

public abstract class RecordFactory {    abstract Record createRec();}

文件工厂

public class DocFactory extends RecordFactory {    @override    Record createRec() {        return new DocRecord();        }}

数据库工厂

public class DbFactory extends RecordFactory {    @override    Record createRec() {        return new DbRecord();        }}

抽象的产品

abstract class Record {    abstract void operate();}

文件产品

public class DocRecord extends Record{    @override    void operate() {        System.out.println("DocRecordOperate");    }}

数据库产品

public class DbRecord extends Record{    @override    void operate() {        System.out.println("DbRecordOperate");    }}

增加了控制台记录的类图

2.某系统为了改进数据库操作的性能，自定义数据连接对象Connection和语句对象Statement，可针对不同类型的数据库提供不同的连接对象和语句对象；用户可以通过配置文件等方式根据实际需要动态更换系统数据库；使用Abstract Factory模式来设计。

抽象工厂类

public abstract class DbFactory {    abstract Statement createStatement();    abstract Connection createConnection();}

MySql工厂类

public class MySqlFactory extends DbFactory{    @override    Statement createStatement() {        return new MySqlStatement;    }    Connection createConnection() {        return new MySqlConnection;    }}

Oracle工厂类

public class OracleFactory{    @override    Statement createStatement() {        return new OracleStatement;    }    Connection createConnection() {        return new OracleConnection;    }}

SqlServer工厂类

public class SqlServerFactory{    @override    Statement createStatement() {        return new SqlServerStatement;    }    Connection createConnection() {        return new SqlServerConnection;    }}

Statement语句对象类

public abstract class Statement {    abstract void operate();}

Connection连接对象类

public abstract class Connection {    abstract void connect();}

MySql语句对象

public class MySqlStatement extends Statement{    @override    public void operate() {        System.out.println("MySqlStatement");    }}

MySql连接对象

public class MySqlConnection extends Connection{    @override    public void connect() {        System.out.println("MySqlConnection");    }}

3.KFC套餐是一个复杂对象，一般包括主食（如汉堡、鸡肉卷等）和饮料（如果汁、可乐等）组成部分，不同套餐有不同组成部分；KFC服务员要根据顾客要求，装配这些组成部分，构造一个完整套餐，返回给顾客；使用Builder模式来设计。

抽象建造类

public abstract class CombinationBuilder {    private Combination com;    public abstract void buildFood();    public abstract void buildDrink();        public Combination() {        return com;    }}

到眼类

public class Director{    public void build(CombinationBuilder comBuilder) {        comBuilder.buildDrink();        comBuilder.buildFood();    }}

普通套餐类

public class NormalCombination extends CombinationBuilder{    @override    void buildFood() {        com.add("whateverFood");    }        void buildDrink() {        com.add("whateverDrink");    }}

套餐类

public class Combination{    private List
    
      list = new LinkedList
     
      ();    public void add(String thing) {        list.add(thing);    }    public void show() {        System.out.println("combination");    }}
     
    

4.游戏中的地图：包括天空、地面、背景；人物包括人体、服装、装备等组成部分，如采用Builder模式如何设计？

导演类

public class LevelDirector{    public void buildMap(MapBuilder mapBuilder) {        mapBuilder.buildSky();        mapBuilder.buildTerrain();        mapBuilder.buildBackground();    }    public void buildRole(RoleBuilder roleBuilder) {        roleBuilder.buildBody();        roleBuilder.buildOutfit();        roleBuilder.buildArmer();    }}

地图构建类

public abstract class MapBuilder {    private Map map;    public abstract void buildSky();    public abstract void buildTerrain();    public abstract void buildBackground();        public Map getMap() {        return map;    }}

角色构建类

public abstract class RoleBuilder {    private Player role;    public abstract void buildBody();    public abstract void buildOutfit();    public abstract void buildArmer();        public Map getRole() {        return role;    }}

菜鸟角色构建类

public class NoobRole extends RoleBuilder{    @override    void buildBody() {        Role.add("WeakBody");    }        void buildOutfit() {        Role.add("Original-Outfit");    }    void buildArmer() {        Role.add("Original-Armer");    }}

玩家类

public class Player{    List
    
      list = new LinkedList
     
      ();    public void add(String thing) {        list.add(thing);    }    public void show() {        System.out.println("Player");    }}
     
    

5.某系统需要提供一个加密模块，将用户信息（如密码等）加密之后再存储在数据库中，系统已经定义好数据库操作类。为了提高开发效率，现要重用已有的加密算法，这些算法由第三方提供，没有源码。如采用Adapter模式如何设计？

原有接口

public interface NoEncryption {    void encrypt();}

数据库类

public class DataBase{    private NoEncryption noEncryption;        public DataBase() {}        public DataBase(NoEncryption noEncryption) {        this.noEncryption=noEncryption;    }    public void setEncryption(NoEncryption noEncryption) {        this.noEncryption=noEncryption;    }        public void encrypt() {        System.out.println("noEncryption");    }}

适配体类

public class Adaptee{    public void encrypt() {        System.out.println("Encryption");    }}

适配器类

public class EncryptionAdapter implements NoEncryption{    private Adaptee adaptee;        public EncryptionAdapter(Adaptee adaptee) {        this.adaptee=adaptee;    }        public void encrypt() {        System.out.println("Encryption");    }}