一个已有的Struts+Spring+Hibernate项目,以前使用MySQL数据库,现在想把Redis也整合进去。
1. 相关Jar文件
下载并导入以下3个Jar文件:
commons-pool2-2.4.2.jar、jedis-2.3.1.jar、spring-data-redis-1.3.4.RELEASE.jar。
2. Redis配置文件
在src文件夹下面新建一个redis.properties文件,设置连接Redis的一些属性。
redis.host=127.0.0.1 redis.port=6379 redis.default.db=1 redis.timeout=100000 redis.maxActive=300 redis.maxIdle=100 redis.maxWait=1000 redis.testOnBorrow=true
再新建一个redis.xml文件。
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p" xmlns:context="http://www.springframework.org/schema/context" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd"> <context:property-placeholder location="classpath:redis.properties"/> <bean id="propertyConfigurerRedis" class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"> <property name="order" value="1" /> <property name="ignoreUnresolvablePlaceholders" value="true" /> <property name="systemPropertiesMode" value="1" /> <property name="searchSystemEnvironment" value="true" /> <property name="locations"> <list> <value>classpath:redis.properties</value> </list> </property> </bean> <bean id="jedisPoolConfig" class="redis.clients.jedis.JedisPoolConfig"> <property name="maxIdle" value="${
redis.maxIdle}
" /> <property name="testOnBorrow" value="${
redis.testOnBorrow}
" /> </bean> <bean id="jedisConnectionFactory" class="org.springframework.data.redis.connection.jedis.JedisConnectionFactory"> <property name="usePool" value="true"></property> <property name="hostName" value="${
redis.host}
" /> <property name="port" value="${
redis.port}
" /> <property name="timeout" value="${
redis.timeout}
" /> <property name="database" value="${
redis.default.db}
"></property> <constructor-arg index="0" ref="jedisPoolConfig" /> </bean> <bean id="redisTemplate" class="org.springframework.data.redis.core.StringRedisTemplate" p:connectionFactory-ref="jedisConnectionFactory" > </bean> <bean id="redisBase" abstract="true"> <property name="template" ref="redisTemplate"/> </bean> <context:component-scan base-package="com.school.redisclient" /> </beans>
3. Redis类
新建一个com.school.redisclient包,结构如下:
接口IRedisService:
public interface IRedisService<K, V> {
public void set(K key, V value, long expiredTime);
public V get(K key);
public Object getHash(K key, String name);
public void del(K key);
}
抽象类AbstractRedisService,主要是对RedisTemplate进行操作:
public abstract class AbstractRedisService<K, V> implements IRedisService<K, V> {
@Autowired private RedisTemplate<K, V> redisTemplate;
public RedisTemplate<K, V> getRedisTemplate() {
return redisTemplate;
}
public void setRedisTemplate(RedisTemplate<K, V> redisTemplate) {
this.redisTemplate = redisTemplate;
}
@Override public void set(final K key, final V value, final long expiredTime) {
BoundValueOperations<K, V> valueOper = redisTemplate.boundValueOps(key);
if (expiredTime <= 0) {
valueOper.set(value);
}
else {
valueOper.set(value, expiredTime, TimeUnit.MILLISECONDS);
}
}
@Override public V get(final K key) {
BoundValueOperations<K, V> valueOper = redisTemplate.boundValueOps(key);
return valueOper.get();
}
@Override public Object getHash(K key, String name){
Object res = redisTemplate.boundHashOps(key).get(name);
return res;
}
@Override public void del(K key) {
if (redisTemplate.hasKey(key)) {
redisTemplate.delete(key);
}
}
}
实现类RedisService:
@Service("redisService") public class RedisService extends AbstractRedisService<String, String> {
}
工具类RedisTool:
public class RedisTool {
private static ApplicationContext factory;
private static RedisService redisService;
public static ApplicationContext getFactory(){
if (factory == null){
factory = new ClassPathXmlApplicationContext("classpath:redis.xml");
}
return factory;
}
public static RedisService getRedisService(){
if (redisService == null){
redisService = (RedisService) getFactory().getBean("redisService");
}
return redisService;
}
}
4. 查询功能的实现
新建一个Action:RClasQueryAction,返回Redis里面所有的课程数据。
@SuppressWarnings("serial")public class RClasQueryAction extends ActionSupport {
RedisService rs = RedisTool.getRedisService();
List<Clas> claslist = new ArrayList<Clas>();
Clas c;
public String execute(){
if (rs != null){
System.out.println("RedisService : " + rs);
getAllClas();
}
ServletActionContext.getRequest().setAttribute("claslist", claslist);
return SUCCESS;
}
private void getAllClas(){
claslist = new ArrayList<Clas>();
int num = Integer.parseInt(rs.get("clas:count"));
for (int i=0;
i<num;
i++){
String cid = "clas:" + (i+1);
c = new Clas();
int id = Integer.parseInt(String.valueOf(rs.getHash(cid, "ID")));
c.setId(id);
System.out.println("ID:" + id);
String name = (String) rs.getHash(cid, "NAME");
c.setName(name);
System.out.println("NAME:" + name);
String comment = (String) rs.getHash(cid, "COMMENT");
c.setComment(comment);
System.out.println("COMMENT:" + comment);
claslist.add(c);
}
}
}
Struts的设置和jsp文件就不详细讲了。
5. Redis数据库
Redis数据库里面的内容(使用的是Redis Desktop Manager):
最后是运行结果:
当然,这只是实现了从Redis查询数据,还没有实现将Redis作为MySQL的缓存。
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。
以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持脚本之家。