工厂模式主要是为创建对象提供接口,工厂模式有可以分为三类:
1,简单工厂模式
①,抽象角色
②,具体角色
③工厂角色
2,工厂方法模式(每个具体角色由其具体工厂产生),
①,抽象角色
②,具体角色
③,抽象工厂
④,具体工厂
3,抽象工厂模式(与工厂模式区别在于创建对象的复杂程度上)
一,简单工厂模式也称静态工厂方法
抽象类角色:一般是接口或者抽象类,由具体类角色继承或实现。
具体类角色:实现或继承抽象类,工厂角色创建具体类角色的实例
工厂角色:一般为一个具体类实现,创建具体类角色。
抽象类角色,定义为一个Nosql接口:
package com.myjava.factory;
public interface NosqlInterface {
public void read();
public void write();
}
具体类角色:
包含Nosql的几种实现类,Hadoop.java,Memcache.java.Redis.java,Mongodb.java
package com.myjava.factory;
public class Hadoop implements NosqlInterface {
public void read() {
System.out.println("hadoop read");
}
public void write() {
System.out.println("hadoop write");
}
}
-------------------------
package com.myjava.factory;
public class Memcache implements NosqlInterface {
public void read() {
System.out.println("memcache read");
}
public void write() {
System.out.println("memcache write");
}
}
----------------------------------
package com.myjava.factory;
public class Mongodb implements NosqlInterface {
public void read() {
System.out.println("mongodb read");
}
public void write() {
System.out.println("mongodb write");
}
}
-----------------------------------
package com.myjava.factory;
public class Redis implements NosqlInterface {
public void read() {
System.out.println("Redis read");
}
public void write() {
System.out.println("Redis write");
}
}
------------------------------------------------------------
工厂类角色
package com.myjava.factory;
public class NosqlFactory {
public static NosqlInterface nosqlCreateFactory(String nosqlName) throws Exception{
if(nosqlName.equals("hadoop")){
return new Hadoop();
}
if(nosqlName.equals("redis")){
return new Redis();
}
if(nosqlName.equals("memcache")){
return new Memcache();
}
if(nosqlName.equals("mongodb")){
return new Mongodb();
}else{
throw new Exception();
}
}
}
再来个简单的测试例子:
package com.myjava.factory;
public class NosqlDriverClient {
public static void main(String[] args){
try {
Hadoop hadoop =NosqlFactory.nosqlCreateFactory("hadoop");
hadoop.read();
hadoop.write();
Memcache memcache = (Memcache) nosqlFactory.nosqlCreateFactory("memcache");
memcache.read();
memcache.write();
Redis redis = (Redis) nosqlFactory.nosqlCreateFactory("redis");
redis.read();
redis.write();
Mongodb mongodb = (Mongodb) nosqlFactory.nosqlCreateFactory("mongodb");
mongodb.write();
mongodb.read();
} catch (Exception e) {
e.printStackTrace();
}
}
}
---------------------
运行结果:
hadoop read
hadoop write
memcache read
memcache write
Redis read
Redis write
mongodb write
mongodb read