【Spring】17、spring cache 与redis缓存整合

spring cache,基本能够满足一般应用对缓存的需求,但现实总是很复杂,当你的用户量上去或者性能跟不上,总需要进行扩展,这个时候你或许对其提供的内存缓存不满意了,因为其不支持高可用性,也不具备持久化数据能力,这个时候,你就需要自定义你的缓存方案了,还好,spring 也想到了这一点。

本篇文章采用spring cache与Redis进行整合,实现自己想要的缓存。

我们先配置redis:

第一步,要安装redis,这个自行百度,我们主要是配置redis。

增加一个redis配置文件,可以放在跟目录下

redis.host=192.168.0.43
redis.port=6379
redis.pass=2015
redis.maxIdle=50
redis.maxActive=50
redis.maxWait=50
redis.testOnBorrow=true
redis.timeout=1000

还需要在spring的配置文件中去配置redis

<context:property-placeholder location="classpath:conf/redis.properties" />

    <bean id="poolConfig" class="redis.clients.jedis.JedisPoolConfig">
        <property name="maxIdle" value="${redis.maxIdle}" />
        <property name="maxTotal" value="${redis.maxActive}" />
        <property name="maxWaitMillis" value="${redis.maxWait}" />
        <property name="testOnBorrow" value="${redis.testOnBorrow}" />
    </bean>

    <bean id="connectionFactory"
        class="org.springframework.data.redis.connection.jedis.JedisConnectionFactory">
        <property name="poolConfig" ref="poolConfig" />
        <property name="port" value="${redis.port}" />
        <property name="hostName" value="${redis.host}" />
        <property name="password" value="${redis.pass}" />
        <property name="timeout" value="${redis.timeout}" />
    </bean>

    <bean id="redisTemplate" class="org.springframework.data.redis.core.RedisTemplate">
        <property name="connectionFactory" ref="connectionFactory" />
    </bean>

好了,配置redis完成了。

现在我们来配置spring的cache:

<?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:cache="http://www.springframework.org/schema/cache"
    xmlns:p="http://www.springframework.org/schema/p"
    xsi:schemaLocation="http://www.springframework.org/schema/beans 
   http://www.springframework.org/schema/beans/spring-beans.xsd 
     http://www.springframework.org/schema/cache 
     http://www.springframework.org/schema/cache/spring-cache.xsd">

    <cache:annotation-driven />

    <!-- 缓存管理器 -->
    <bean id="cacheManager" class="org.springframework.cache.support.SimpleCacheManager">
        <property name="caches">
            <set>
                <bean class="com.config.SystemRedisCache">
                    <property name="redisTemplate" ref="redisTemplate" />
                    <property name="name" value="default" />
                    <property name="timeout" value="${redis.timeout}" />
                </bean>
                <bean class="com.config.SystemRedisCache">
                    <property name="redisTemplate" ref="redisTemplate" />
                    <property name="name" value="commonService.queryCityListByParentCode" />
                    <property name="timeout" value="${redis.timeout}" />
                </bean>
                <bean class="com.config.SystemRedisCache">
                    <property name="redisTemplate" ref="redisTemplate" />
                    <property name="name"
                        value="commonService.queryIndustryListByParentCode" />
                    <property name="timeout" value="${redis.timeout}" />
                </bean>
                <bean class="com.config.SystemRedisCache">
                    <property name="redisTemplate" ref="redisTemplate" />
                    <property name="name" value="commonService.queryIndustryInfoById" />
                    <property name="timeout" value="${redis.timeout}" />
                </bean>
                <bean class="com.config.SystemRedisCache">
                    <property name="redisTemplate" ref="redisTemplate" />
                    <property name="name" value="commonService.queryIndustryNameByIds" />
                    <property name="timeout" value="${redis.timeout}" />
                </bean>
                <bean class="com.config.SystemRedisCache">
                    <property name="redisTemplate" ref="redisTemplate" />
                    <property name="name" value="commonService.queryCityNameByIds" />
                    <property name="timeout" value="${redis.timeout}" />
                </bean>
                <bean class="com.config.SystemRedisCache">
                    <property name="redisTemplate" ref="redisTemplate" />
                    <property name="name" value="commonService.isSpecialSchool" />
                    <property name="timeout" value="${redis.timeout}" />
                </bean>
                <bean class="com.config.SystemRedisCache">
                    <property name="redisTemplate" ref="redisTemplate" />
                    <property name="name" value="commonService.getProvinceByCity" />
                    <property name="timeout" value="${redis.timeout}" />
                </bean>
                <bean class="com.config.SystemRedisCache">
                    <property name="redisTemplate" ref="redisTemplate" />
                    <property name="name" value="permissionService.queryMenuList" />
                    <property name="timeout" value="${redis.timeout}" />
                </bean>
                <bean class="com.config.SystemRedisCache">
                    <property name="redisTemplate" ref="redisTemplate" />
                    <property name="name" value="permissionService.queryOperationOfMenu" />
                    <property name="timeout" value="${redis.timeout}" />
                </bean>
                <bean class="com.config.SystemRedisCache">
                    <property name="redisTemplate" ref="redisTemplate" />
                    <property name="name" value="roleService.queryAllRole" />
                    <property name="timeout" value="${redis.timeout}" />
                </bean>
                <bean class="com.config.SystemRedisCache">
                    <property name="redisTemplate" ref="redisTemplate" />
                    <property name="name" value="permissionService.queryPermissionTree" />
                    <property name="timeout" value="${redis.timeout}" />
                </bean>
                <bean class="com.config.SystemRedisCache">
                    <property name="redisTemplate" ref="redisTemplate" />
                    <property name="name"
                        value="permissionService.queryPermissaionMenuByRoleCode" />
                    <property name="timeout" value="${redis.timeout}" />
                </bean>
                <bean class="com.config.SystemRedisCache">
                    <property name="redisTemplate" ref="redisTemplate" />
                    <property name="name"
                        value="permissionService.queryAllPermissionByRoleCode" />
                    <property name="timeout" value="${redis.timeout}" />
                </bean>
            </set>
        </property>
        <!-- <property name="fallbackToNoOpCache" value="false"/> -->
    </bean>
</beans>

其实上面的配置文件,已经把redis与spring注解缓存的关系配置到了spring的xml文件中了。

对应的SystemRedisCache类是一个实现cache接口的自定义的缓存实现类。

import org.springframework.cache.Cache;
import org.springframework.cache.support.SimpleValueWrapper;
import org.springframework.dao.DataAccessException;
import org.springframework.data.redis.connection.RedisConnection;
import org.springframework.data.redis.core.RedisCallback;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.util.StringUtils;

/**
 * 〈一句话功能简述〉<br>
 * 〈功能详细描述〉
 * 
 * @author Administrator
 * @see [相关类/方法](可选)
 * @since [产品/模块版本] (可选)
 */
public class SystemRedisCache implements Cache {

    /**
     * Redis
     */
    private RedisTemplate<String, Object> redisTemplate;

    /**
     * 缓存名称
     */
    private String name;

    /**
     * 超时时间
     */
    private long timeout;

    /*
     * (non-Javadoc)
     * @see org.springframework.cache.Cache#getName()
     */
    @Override
    public String getName() {
        return this.name;
    }

    /*
     * (non-Javadoc)
     * @see org.springframework.cache.Cache#getNativeCache()
     */
    @Override
    public Object getNativeCache() {
        // TODO Auto-generated method stub
        return this.redisTemplate;
    }

    /*
     * (non-Javadoc)
     * @see org.springframework.cache.Cache#get(java.lang.Object)
     */
    @Override
    public ValueWrapper get(Object key) {
        if (StringUtils.isEmpty(key)) {
            return null;
        } else {
            final String finalKey;
            if (key instanceof String) {
                finalKey = (String) key;
            } else {
                finalKey = key.toString();
            }
            Object object = null;
            object = redisTemplate.execute(new RedisCallback<Object>() {
                public Object doInRedis(RedisConnection connection) throws DataAccessException {
                    byte[] key = finalKey.getBytes();
                    byte[] value = connection.get(key);
                    if (value == null) {
                        return null;
                    }
                    return SerializableObjectUtil.unserialize(value);
                }
            });
            return (object != null ? new SimpleValueWrapper(object) : null);
        }
    }

    /*
     * (non-Javadoc)
     * @see org.springframework.cache.Cache#get(java.lang.Object, java.lang.Class)
     */
    @SuppressWarnings("unchecked")
    @Override
    public <T> T get(Object key, Class<T> type) {
        if (StringUtils.isEmpty(key) || null == type) {
            return null;
        } else {
            final String finalKey;
            final Class<T> finalType = type;
            if (key instanceof String) {
                finalKey = (String) key;
            } else {
                finalKey = key.toString();
            }
            final Object object = redisTemplate.execute(new RedisCallback<Object>() {
                public Object doInRedis(RedisConnection connection) throws DataAccessException {
                    byte[] key = finalKey.getBytes();
                    byte[] value = connection.get(key);
                    if (value == null) {
                        return null;
                    }
                    return SerializableObjectUtil.unserialize(value);
                }
            });
            if (finalType != null && finalType.isInstance(object) && null != object) {
                return (T) object;
            } else {
                return null;
            }
        }
    }

    /*
     * (non-Javadoc)
     * @see org.springframework.cache.Cache#put(java.lang.Object, java.lang.Object)
     */
    @Override
    public void put(final Object key, final Object value) {
        if (StringUtils.isEmpty(key) || StringUtils.isEmpty(value)) {
            return;
        } else {
            final String finalKey;
            if (key instanceof String) {
                finalKey = (String) key;
            } else {
                finalKey = key.toString();
            }
            if (!StringUtils.isEmpty(finalKey)) {
                final Object finalValue = value;
                redisTemplate.execute(new RedisCallback<Boolean>() {
                    @Override
                    public Boolean doInRedis(RedisConnection connection) {
                        connection.set(finalKey.getBytes(), SerializableObjectUtil.serialize(finalValue));
                        // 设置超时间
                        connection.expire(finalKey.getBytes(), timeout);
                        return true;
                    }
                });
            }
        }
    }

    /*
     * 根据Key 删除缓存
     */
    @Override
    public void evict(Object key) {
        if (null != key) {
            final String finalKey;
            if (key instanceof String) {
                finalKey = (String) key;
            } else {
                finalKey = key.toString();
            }
            if (!StringUtils.isEmpty(finalKey)) {
                redisTemplate.execute(new RedisCallback<Long>() {
                    public Long doInRedis(RedisConnection connection) throws DataAccessException {
                        return connection.del(finalKey.getBytes());
                    }
                });
            }
        }
    }

    /*
     * 清楚系统缓存
     */
    @Override
    public void clear() {
        // TODO Auto-generated method stub
        // redisTemplate.execute(new RedisCallback<String>() {
        // public String doInRedis(RedisConnection connection) throws DataAccessException {
        // connection.flushDb();
        // return "ok";
        // }
        // });
    }

    public RedisTemplate<String, Object> getRedisTemplate() {
        return redisTemplate;
    }

    public void setRedisTemplate(RedisTemplate<String, Object> redisTemplate) {
        this.redisTemplate = redisTemplate;
    }

    public void setName(String name) {
        this.name = name;
    }

    public long getTimeout() {
        return timeout;
    }

    public void setTimeout(long timeout) {
        this.timeout = timeout;
    }
}

主要的方法就是get和put方法,里面的逻辑都是根据我们自己的需求去实现的。


现在有个问题,我们发现,在spring配置自己的注解缓存的配置文件中配置了多个cache,那spring是怎么去找到对应的cacheManager呢?

我们直接以代码给大家呈现出来:

/**
 * 
 * 公共接口
 * 
 * @author Administrator
 * @see [相关类/方法](可选)
 * @since [产品/模块版本] (可选)
 */
@Service("commonService")
public class CommonServiceImpl implements CommonService {

    /**
     * 日志记录器
     */
    private static final Logger LOGGER = LoggerFactory.getLogger(CommonServiceImpl.class);

    @Autowired
    private DalClient dalClient;

    /*
     * @Autowired RedisTemplate<?, ?> redisTemplate;
     */

    /**
     * 根据名称获取自增序列squence的当前值
     * 
     * @param SequenceName 自增序列名称
     * @return 自增序列当前值
     * @see [相关类/方法](可选)
     * @since [产品/模块版本](可选)
     */
    @Override
    public String getSequenceByName(String SequenceName) {
        if (StringUtils.isEmpty(SequenceName)) {
            LOGGER.error("自增序列名称为空,无法返回正常的自增序列值");
            return null;
        } else {
            Map<String, String> paramMap = new HashMap<String, String>();
            paramMap.put("sequenceName", SequenceName);
            // 查询sequence当前值
            Map<String, Object> resultMap = dalClient.queryForMap("common.GET_SEQUENCE_BY_NAME", paramMap);
            if (null != resultMap && !resultMap.isEmpty()) {
                return String.valueOf(resultMap.get("sequenceValue"));
            } else {
                return null;
            }
        }
    }

    /**
     * 根据上一级的城市编码 查询 所有下属城市 列表
     * 
     * @param parentCityCode
     * @return
     * @see [相关类/方法](可选)
     * @since [产品/模块版本](可选)
     */
    @Override
    @Cacheable(value = "commonService.queryCityListByParentCode", key = "new String('commonService.queryCityListByParentCode')+#parentCityCode.toString()", condition = "null != #parentCityCode")
    public List<CityBean> queryCityListByParentCode(final Integer parentCityCode) {
        Map<String, Object> paramMap = new HashMap<String, Object>();
        if (null != parentCityCode) {
            // 根据所选省份  城市 查询所属城市列表
            paramMap.put("parentCityCode", parentCityCode);

            final List<CityBean> cityListResult = dalClient.queryForList("T_CITY.SELECT_BY_PARENTCODE", paramMap,
                    CityBean.class);
            return cityListResult;
        } else {
            final List<CityBean> provinceListResult = dalClient.queryForList("T_CITY.SELECT_ALL_FIRST_STEP_CITY",
                    paramMap, CityBean.class);
            return provinceListResult;
        }
    }

    /**
     * 根据上一级的行业编码 查询 所有下属所有行业
     * 
     * @param parentCityCode
     * @return
     * @see [相关类/方法](可选)
     * @since [产品/模块版本](可选)
     */
    @Override
    @Cacheable(value = "commonService.queryIndustryListByParentCode", key = "new String('commonService.queryIndustryListByParentCode')+#parentIndustryCode.toString", condition = "null != #parentIndustryCode")
    public List<IndustryBean> queryIndustryListByParentCode(final Integer parentIndustryCode) {
        Map<String, Object> paramMap = new HashMap<String, Object>();
        if (null != parentIndustryCode) {
            paramMap.put("parentIndustryCode", parentIndustryCode);
            final List<IndustryBean> industryListResult = dalClient.queryForList("T_INDUSTRY.SELECT_BY_PARENTCODE",
                    paramMap, IndustryBean.class);
            return industryListResult;
        } else {
            final List<IndustryBean> industryListResult = dalClient.queryForList(
                    "T_INDUSTRY.SELECT_ALL_FIRST_STEP_INDUSTRY", paramMap, IndustryBean.class);
            return industryListResult;
        }
    }

    /**
     * 根据行业编码查询 行业信息
     * 
     * @param industryCode
     * @return
     * @see [相关类/方法](可选)
     * @since [产品/模块版本](可选)
     */
    @Override
    @Cacheable(value = "commonService.queryIndustryInfoById", key = "new String('commonService.queryIndustryInfoById')+#industryCode", condition = "(null != #industryCode) and (#industryCode.length() > 0)")
    public IndustryBean queryIndustryInfoById(final String industryCode) {
        if (StringUtils.isEmpty(industryCode)) {
            return null;
        } else {
            Map<String, Object> paramMap = new HashMap<String, Object>();
            paramMap.put("industryCode", industryCode);
            final IndustryBean industryInfoResult = dalClient.queryForObject("T_INDUSTRY.SELECT_BY_ID", paramMap,
                    IndustryBean.class);
            return industryInfoResult;
        }
    }

    /**
     * 递归删除 元素 因为可能存在重复的
     * 
     * @param list 列表
     * @param item 要删除的元素
     * @see [相关类/方法](可选)
     * @since [产品/模块版本](可选)
     */
    private void deleteListElement(ArrayList<String> list, String item) {
        if (null != list && !list.isEmpty() && StringUtils.isNotBlank(item)) {
            if (list.contains(item)) {
                list.remove(item);
                if (list.contains(item)) {
                    deleteListElement(list, item);
                }
            }
        }
    }

    /**
     * 根据行业id查询 行业名称
     * 
     * @param industryIds 行业Id可能有多个 以分号分隔
     * @return 行业名称列表
     * @see [相关类/方法](可选)
     * @since [产品/模块版本](可选)
     */
    @Override
    @Cacheable(value = "commonService.queryIndustryNameByIds", key = "new String('commonService.queryIndustryNameByIds')+#industryIds", condition = "null != #industryIds and #industryIds.length() > 0")
    public List<String> queryIndustryNameByIds(final String industryIds) {
        if (StringUtils.isBlank(industryIds)) {
            return null;
        } else {
            String[] industryIdArr = industryIds.split(";");
            if (null != industryIdArr && industryIdArr.length > 0) {
                ArrayList<String> paramList = new ArrayList<String>();
                paramList.addAll(Arrays.asList(industryIdArr));
                if (null != paramList && !paramList.isEmpty()) {
                    Map<String, Object> paramMap = new HashMap<String, Object>();
                    paramMap.put("industryIdList", paramList);
                    // 查询行业列表
                    List<IndustryBean> queryResultList = dalClient.queryForList("T_INDUSTRY.SELECT_BY_ID_LIST",
                            paramMap, IndustryBean.class);
                    // 封装查询结果
                    List<String> industryNameList = new ArrayList<String>();
                    if (null != queryResultList && !queryResultList.isEmpty()) {
                        // 遍历查询列表 将已经存在的编码去掉 剩下的 就是 根據编码查询不出行业的 直接将行业的名字返回
                        String tempId;
                        for (IndustryBean industryInfo : queryResultList) {
                            if (null != industryInfo) {
                                if (null == industryInfo.getIndustryCode()) {
                                    continue;
                                } else {
                                    tempId = industryInfo.getIndustryCode().toString();
                                    if (paramList.contains(tempId)) {
                                        deleteListElement(paramList, tempId);
                                    }
                                    if (StringUtils.isNotBlank(industryInfo.getIndustryName())) {
                                        industryNameList.add(industryInfo.getIndustryName());
                                    }
                                }
                            }
                        }
                    }
                    // 将根据编码查询不出来 的 行业编码 直接返回
                    industryNameList.addAll(paramList);
                    return industryNameList;
                }
            }
            return null;
        }
    }

    /**
     * 根据城市id查询 城市名称
     * 
     * @param industryIds 行业Id可能有多个 以分号分隔
     * @return 行业名称列表
     * @see [相关类/方法](可选)
     * @since [产品/模块版本](可选)
     */
    @Override
    @Cacheable(value = "commonService.queryCityNameByIds", key = "new String('commonService.queryCityNameByIds')+#cityIds", condition = "null != #cityIds and #cityIds.length() > 0")
    public List<String> queryCityNameByIds(String cityIds) {
        if (StringUtils.isBlank(cityIds)) {
            return null;
        } else {
            String replacyedCityIds = cityIds.replace(";", ",");
            String[] industryIdArr = replacyedCityIds.split(",");
            if (null != industryIdArr && industryIdArr.length > 0) {
                ArrayList<String> paramList = new ArrayList<String>();
                paramList.addAll(Arrays.asList(industryIdArr));
                if (null != paramList && !paramList.isEmpty()) {
                    Map<String, Object> paramMap = new HashMap<String, Object>();
                    paramMap.put("cityIdList", paramList);
                    // 查询行业列表
                    List<CityBean> queryResultList = dalClient.queryForList("T_CITY.SELECT_BY_ID_LIST", paramMap,
                            CityBean.class);
                    List<String> industryNameList = new ArrayList<String>();
                    if (null != queryResultList && !queryResultList.isEmpty()) {
                        // 遍历查询列表 将已经存在的编码去掉 剩下的 就是 根據编码查询不出行业的 直接将行业的名字返回
                        // 封装查询结果
                        String tempId;
                        for (CityBean industryInfo : queryResultList) {
                            if (null != industryInfo) {
                                if (null == industryInfo.getCityCode()) {
                                    continue;
                                } else {
                                    tempId = industryInfo.getCityCode().toString();
                                    if (paramList.contains(tempId)) {
                                        deleteListElement(paramList, tempId);
                                    }
                                    if (StringUtils.isNotBlank(industryInfo.getCityName())) {
                                        industryNameList.add(industryInfo.getCityName());
                                    }
                                }
                            }
                        }
                    }
                    // 将根据编码查询不出来 的 行业编码 直接返回
                    industryNameList.addAll(paramList);
                    return industryNameList;
                }
            }
            return null;
        }
    }

    /**
     * 查询第一级所有职位
     * 
     * @return
     */
    @Override
    public List<JobTypeVo> queryFirstJobList() {
        /*
         * List<JobTypeVo> redisIndustryListResult = redisTemplate.execute(new RedisCallback<List<JobTypeVo>>() {
         * @Override public List<JobTypeVo> doInRedis(RedisConnection connection) { byte[] industryListList =
         * connection.get((RedisConstants.JOB_FIRST_LIST).getBytes()); if (null != industryListList &&
         * industryListList.length > 0) { return (List<JobTypeVo>) SerializableObjectUtil.unserialize(industryListList);
         * } else { return null; } } }); if (null != redisIndustryListResult && !redisIndustryListResult.isEmpty()) {
         * return redisIndustryListResult; } else {
         */
        final List<JobTypeVo> queryIndustryListResult = dalClient.queryForList("T_JOB_TYPE.SELECT_FIRST_JOB_CODE",
                null, JobTypeVo.class);
        /*
         * if (null != queryIndustryListResult && !queryIndustryListResult.isEmpty()) { redisTemplate.execute(new
         * RedisCallback<Boolean>() {
         * @Override public Boolean doInRedis(RedisConnection connection) {
         * connection.set((RedisConstants.JOB_FIRST_LIST).getBytes(),
         * SerializableObjectUtil.serialize(queryIndustryListResult)); return true; } }); }
         */
        return queryIndustryListResult;
        /* } */
    }

    /**
     * 查询 对应级别的职位信息
     * 
     * @param typeValue
     * @param jobCode
     * @return
     */
    @Override
    public List<JobTypeBean> queryJobTypeList(final int typeValue, final int jobCode) {
        /*
         * List<JobTypeBean> redisIndustryListResult = redisTemplate.execute(new RedisCallback<List<JobTypeBean>>() {
         * @Override public List<JobTypeBean> doInRedis(RedisConnection connection) { byte[] industryListList =
         * connection.get((RedisConstants.JOB_FIRST_LIST + typeValue + jobCode) .getBytes()); if (null !=
         * industryListList && industryListList.length > 0) { return (List<JobTypeBean>)
         * SerializableObjectUtil.unserialize(industryListList); } else { return null; } } }); if (null !=
         * redisIndustryListResult && !redisIndustryListResult.isEmpty()) { return redisIndustryListResult; } else {
         */
        Map<String, Object> paramMap = new HashMap<String, Object>();
        paramMap.put("typeValue", typeValue);
        paramMap.put("jobFirstCode", jobCode);
        final List<JobTypeBean> queryResult = dalClient.queryForList("T_JOB_TYPE.SELECT_BY_JOB_CODE", paramMap,
                JobTypeBean.class);
        /*
         * if (null != queryResult && !queryResult.isEmpty()) { redisTemplate.execute(new RedisCallback<Boolean>() {
         * @Override public Boolean doInRedis(RedisConnection connection) {
         * connection.set((RedisConstants.JOB_FIRST_LIST + typeValue + jobCode).getBytes(),
         * SerializableObjectUtil.serialize(queryResult)); return true; } }); }
         */
        return queryResult;
        /* } */
    }

    /**
     * 判断学校是否 特殊学校
     * 
     * @param schoolName 学校名称
     * @param schoolType 学校分类(1:211 暂无其他)
     * @return true:是, false:否
     * @see [相关类/方法](可选)
     * @since [产品/模块版本](可选)
     */
    @Override
    @Cacheable(value = "commonService.isSpecialSchool", key = "new String('commonService.isSpecialSchool')+#schoolName + #schoolType", condition = "null != #schoolName and null !=#schoolType and #schoolName.length() > 0")
    public boolean isSpecialSchool(String schoolName, int schoolType) {
        if (StringUtils.isEmpty(schoolName)) {
            return false;
        } else {
            Map<String, Object> paramMap = new HashMap<String, Object>();
            paramMap.put("schoolName", schoolName);
            paramMap.put("schoolType", schoolType);
            Map<String, Object> resultMap = dalClient.queryForMap("T_MY_SPECIAL_SCHOOL.SELECT_BY_NAME_TYPE", paramMap);
            if (null != resultMap && !resultMap.isEmpty() && resultMap.containsKey("NUM")) {
                return (long) resultMap.get("NUM") > 0;
            } else {
                return false;
            }
        }
    }

    /**
     * 根据城市名称获取 城市所在 省份名称
     * 
     * @param cityNames
     * @return
     * @see [相关类/方法](可选)
     * @since [产品/模块版本](可选)
     */
    @Override
    @Cacheable(value = "commonService.getProvinceByCity", key = "new String('commonService.getProvinceByCity')+#cityNames", condition = "null != #cityNames and #cityNames.length() > 0")
    public String getProvinceByCity(final String cityNames) {
        if (StringUtils.isBlank(cityNames)) {
            return null;
        } else {
            String[] cityArr = cityNames.split("、");
            Map<String, Object> paramMap = new HashMap<String, Object>();
            Map<String, Object> resultMap;
            String provinceName;
            List<String> provinceLait = new ArrayList<String>();
            for (String cityName : cityArr) {
                if (StringUtils.isNotBlank(cityName)) {
                    paramMap.put("cityName", cityName);
                    resultMap = dalClient.queryForMap("T_CITY.SELECT_PROVINCE_NAMEBY_CITY_NAME", paramMap);
                    if (null != resultMap && !resultMap.isEmpty() && resultMap.containsKey("provinceName")) {
                        provinceName = String.valueOf(resultMap.get("provinceName"));
                        if (!provinceLait.contains(provinceName)) {
                            provinceLait.add(provinceName);
                        }
                    }
                }
            }
            StringBuffer sb = new StringBuffer(100);
            if (!provinceLait.isEmpty()) {
                for (int i = 0; i < provinceLait.size(); i++) {
                    if (i < provinceLait.size() - 1) {
                        sb.append(provinceLait.get(i)).append(",");
                    } else {
                        sb.append(provinceLait.get(i));
                    }
                }
            }
            return sb.toString();
        }
    }

已queryCityListByParentCode方法为例:

在这个方法上面有@Cacheable这个注解,这个是spring3.1以后增加的注解缓存标签,它会根据value = "commonService.queryCityListByParentCode"中value的属性值去查找我们配置在spring的xml文件中的name属性去查找,找到对应的配置文件后,该方法会通过我们自定义的缓存实现类去实现对应的逻辑,如果对spring注解的意义不清楚的可以先去了解下spring cache注解的含义。

友情链接:【Spring】22、Spring缓存注解@Cache使用

原文地址:https://www.cnblogs.com/wangzhongqiu/p/6958655.html