SSH框架和Redis的整合(2)

5. 添加功能的实现

新建一个Action：RClasAction，实现向Redis添加课程数据，并同步到MySQL。

package com.school.action;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;

import com.opensymphony.xwork2.ActionSupport;
import com.school.entity.Clas;
import com.school.redisclient.RedisService;
import com.school.redisclient.RedisTool;
import com.school.service.ClasService;

@SuppressWarnings("serial")
public class RClasAction extends ActionSupport {
    
    @Autowired
    private ClasService clasService;
    
    RedisService rs = RedisTool.getRedisService();
    List<Clas> claslist = new ArrayList<Clas>();
    
    private Clas clas;
    public Clas getClas() {
        return clas;
    }    
    public void setClas(Clas Clas) {
        this.clas = Clas;
    }
    
    public String execute(){
        saveClas(clas);
        return SUCCESS;
    }
    
    @SuppressWarnings({ "rawtypes", "unchecked" })
    private void saveClas(Clas c){
        List<String> ids = rs.getList("clas:id");
        // clas:id
        int num = ids.size();
        int id = Integer.parseInt(ids.get(num-1)) + 1;
        rs.rightPushList("clas:id", String.valueOf(id));
        // clas:count
        int count = Integer.parseInt(rs.get("clas:count"));
        rs.set("clas:count", String.valueOf(count+1), -1);
        // 增加
        HashMap hashmap = new HashMap();
        hashmap.put("ID", String.valueOf(id));
        hashmap.put("NAME", clas.getName());
        hashmap.put("COMMENT", clas.getComment());
        rs.addHash("clas:" + id, hashmap);
        // 同步到MySQL
        clasService.saveClas(clas);
    }

}

clas:id是一个List类型的Key-Value，记录了所有的课程ID，取出最后一个ID，再+1，作为增加的课程的ID，同时clas:count的值也要+1。使用addHash()方法向Redis添加了一个Hash类型的Key-Value(也就是一门课程)：

        @SuppressWarnings({ "unchecked", "rawtypes" })
        public synchronized void addHash(K key, HashMap map){
            redisTemplate.opsForHash().putAll(key, map);
        }

同时将该门课程增加到MySQL。

6. 删除功能的实现

新建一个Action：RClasDeleteAction，实现删除Redis的课程数据，并同步到MySQL。

package com.school.action;

import org.springframework.beans.factory.annotation.Autowired;

import com.opensymphony.xwork2.ActionSupport;
import com.school.redisclient.RedisService;
import com.school.redisclient.RedisTool;
import com.school.service.ClasService;

@SuppressWarnings("serial")
public class RClasDeleteAction extends ActionSupport {
    
    @Autowired
    private ClasService clasService;
    
    RedisService rs = RedisTool.getRedisService();
    
    private int id;
    public int getId(){
        return id;
    }
    public void setId(int id){
        this.id=id;
    }
    
    public String execute(){    
        deleteClas(id);
        // 同步到MySQL
        clasService.deleteClas(id);
        return SUCCESS;
    }
    
    private void deleteClas(int id){
        // 删除
        rs.del("clas:" + id);
        // clas:count
        int count = Integer.parseInt(rs.get("clas:count"));
        rs.set("clas:count", String.valueOf(count-1), -1);
        // clas:id
        rs.delListItem("clas:id", String.valueOf(id));
    }

}

直接删除clas:id，再将clas:count的值-1，这两步比较简单，复杂的是从clas:id中删除该课程的ID，使用了delListItem()方法来实现：

        @Override
        public synchronized void delListItem(K key, V value){
            redisTemplate.opsForList().remove(key, 1, value);
        }

redisTemplate.opsForList().remove()方法类似于LREM命令。最后在MySQL中也删除相同的课程。

7. 修改功能的实现

新建一个Action：RClasUpdateAction，实现删除Redis的课程数据，并同步到MySQL。

package com.school.action;

import java.util.HashMap;

import org.springframework.beans.factory.annotation.Autowired;

import com.opensymphony.xwork2.ActionSupport;
import com.school.entity.Clas;
import com.school.redisclient.RedisService;
import com.school.redisclient.RedisTool;
import com.school.service.ClasService;

@SuppressWarnings("serial")
public class RClasUpdateAction extends ActionSupport{
    
    @Autowired
    private ClasService clasService;
    
    RedisService rs = RedisTool.getRedisService();
    
    private Clas clas;
    public Clas getClas() {
        return clas;
    }
    public void setClas(Clas clas) {
        this.clas = clas;
    }
    
    @SuppressWarnings({ "unchecked", "rawtypes" })
    public String execute(){
        HashMap hashmap = new HashMap();
        hashmap.put("ID", String.valueOf(clas.getId()));
        hashmap.put("NAME", clas.getName());
        hashmap.put("COMMENT", clas.getComment());
        rs.putHash("clas:" + clas.getId(), hashmap);
        // 同步到MySQL
        clasService.updateClas(clas);
        return SUCCESS;
    }

}

使用了putHash()方法来更新：

        @SuppressWarnings({ "rawtypes", "unchecked" })
        @Override
        public synchronized void putHash(K key, HashMap map){
            redisTemplate.boundHashOps(key).putAll(map);
        }

同时在MySQL做相同的更新操作。