正文
自定义注解 怎么玩的 ：
①标记哪个接口需要进行幂等性拦截
②每个接口可以要求幂等性范围时间不一样，举例：可以2秒内，可以3秒内，时间自己传
③ 一旦触发了，提示语可以不同 ，举例：VIP的接口，普通用户的接口，提示语不一样（开玩笑）
效果：
实战开始
核心三件套
注解、拦截器、拦截器配置
① RepeatDaMie.java
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
/**
* @Author: JCccc
* @Date: 2022-6-13 9:04
* @Description: 自定义注解,防止重复提交
*/
@Target({ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
public @interface RepeatDaMie {
/**
* 时间ms限制
*/
public int second() default 1;
/**
* 提示消息
*/
public String describe() default "重复提交了,兄弟";
}②ApiRepeatInterceptor.java
import com.example.repeatdemo.annotation.RepeatDaMie;
import com.example.repeatdemo.util.ContextUtil;
import com.example.repeatdemo.util.Md5Encrypt;
import com.example.repeatdemo.util.RedisUtils;
import com.example.repeatdemo.wrapper.CustomHttpServletRequestWrapper;
import com.fasterxml.jackson.databind.ObjectMapper;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.HandlerInterceptor;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.Objects;
/**
* @Author: JCccc
* @Date: 2022-6-15 9:11
* @Description: 接口幂等性校验拦截器
*/
@Component
public class ApiRepeatInterceptor implements HandlerInterceptor {
private final Logger log = LoggerFactory.getLogger(this.getClass());
private static final String POST="POST";
private static final String GET="GET";
@Override
public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
try {
if (handler instanceof HandlerMethod) {
HandlerMethod handlerMethod = (HandlerMethod) handler;
// 获取RepeatDaMie注解
RepeatDaMie repeatDaMie = handlerMethod.getMethodAnnotation(RepeatDaMie.class);
if (null==repeatDaMie) {
return true;
}
//限制的时间范围
int seconds = repeatDaMie.second();
//这个用户唯一标识，可以自己细微调整，是userId还是token还是sessionId还是不需要
String userUniqueKey = request.getHeader("userUniqueKey");
String method = request.getMethod();
String apiParams = "";
if (GET.equals(method)){
log.info("GET请求来了");
apiParams = new ObjectMapper().writeValueAsString(request.getParameterMap());
}else if (POST.equals(method)){
log.info("POST请求来了");
CustomHttpServletRequestWrapper wrapper = (CustomHttpServletRequestWrapper) request;
apiParams = wrapper.getBody();
}
log.info("当前参数是：{}",apiParams);
// 存储key
String keyRepeatDaMie = Md5Encrypt.md5(userUniqueKey+request.getServletPath()+apiParams) ;
RedisUtils redisUtils = ContextUtil.getBean(RedisUtils.class);
if (Objects.nonNull(redisUtils.get(keyRepeatDaMie))){
log.info("重复请求了，重复请求了，拦截了");
returnData(response,repeatDaMie.describe());
return false;
}else {
redisUtils.setWithTime(keyRepeatDaMie, true,seconds);
}
}
return true;
} catch (Exception e) {
log.warn("请求过于频繁请稍后再试");
e.printStackTrace();
}
return true;
}
public void returnData(HttpServletResponse response,String msg) throws IOException {
response.setCharacterEncoding("UTF-8");
response.setContentType("application/json; charset=utf-8");
ObjectMapper objectMapper = new ObjectMapper();
//这里传提示语可以改成自己项目的返回数据封装的类
response.getWriter().println(objectMapper.writeValueAsString(msg));
return;
}
}③ WebConfig.java
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
/**
* @Author: JCccc
* @Date: 2022-6-15 9:24
* @Description:
*/
@Configuration
public class WebConfig implements WebMvcConfigurer {
@Override
public void addInterceptors(InterceptorRegistry registry) {
registry.addInterceptor(new ApiRepeatInterceptor()).addPathPatterns("/**");
}
}工具类三件套
①ContextUtil.java
import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.stereotype.Component;
/**
* @Author: JCccc
* @Date: 2022-6-15 9:24
* @Description:
*/
@Component
public final class ContextUtil implements ApplicationContextAware {
protected static ApplicationContext applicationContext ;
@Override
public void setApplicationContext(ApplicationContext arg0) throws BeansException {
if (applicationContext == null) {
applicationContext = arg0;
}
}
public static Object getBean(String name) {
//name表示其他要注入的注解name名
return applicationContext.getBean(name);
}
/**
* 拿到ApplicationContext对象实例后就可以手动获取Bean的注入实例对象
*/
public static <T> T getBean(Class<T> clazz) {
return applicationContext.getBean(clazz);
}
}②Md5Encrypt.java
import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
/**
* @Author: JCccc
* @CreateTime: 2018-10-30
* @Description:
*/
public class Md5Encrypt {
private static final char[] DIGITS = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a',
'b', 'c', 'd', 'e', 'f'};
/**
* 对字符串进行MD5加密
*
* @param text 明文
* @return 密文
*/
public static String md5(String text) {
MessageDigest msgDigest = null;
try {
msgDigest = MessageDigest.getInstance("MD5");
} catch (NoSuchAlgorithmException e) {
throw new IllegalStateException("System doesn't support MD5 algorithm.");
}
try {
// 注意该接口是按照指定编码形式签名
msgDigest.update(text.getBytes("UTF-8"));
} catch (UnsupportedEncodingException e) {
throw new IllegalStateException("System doesn't support your EncodingException.");
}
byte[] bytes = msgDigest.digest();
String md5Str = new String(encodeHex(bytes));
return md5Str;
}
private static char[] encodeHex(byte[] data) {
int l = data.length;
char[] out = new char[l << 1];
// two characters form the hex value.
for (int i = 0, j = 0; i < l; i++) {
out[j++] = DIGITS[(0xF0 & data[i]) >>> 4];
out[j++] = DIGITS[0x0F & data[i]];
}
return out;
}
}③RedisUtils.java
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.*;
import org.springframework.stereotype.Component;
import java.io.Serializable;
import java.util.List;
import java.util.Set;
import java.util.concurrent.TimeUnit;
@Component
public class RedisUtils {
@Autowired
private RedisTemplate redisTemplate;
/**
* 写入String型 [ 键，值]
*
* @param key
* @param value
* @return
*/
public boolean set(final String key, Object value) {
boolean result = false;
try {
ValueOperations<Serializable, Object> operations = redisTemplate.opsForValue();
operations.set(key, value);
result = true;
} catch (Exception e) {
e.printStackTrace();
}
return result;
}
/**
* 写入String型,顺便带有过期时间 [ 键，值]
*
* @param key
* @param value
* @return
*/
public boolean setWithTime(final String key, Object value,int seconds) {
boolean result = false;
try {
ValueOperations<Serializable, Object> operations = redisTemplate.opsForValue();
operations.set(key, value,seconds, TimeUnit.SECONDS);
result = true;
} catch (Exception e) {
e.printStackTrace();
}
return result;
}
/**
* 批量删除对应的value
*
* @param keys
*/
public void remove(final String... keys) {
for (String key : keys) {
remove(key);
}
}
/**
* 批量删除key
*
* @param pattern
*/
public void removePattern(final String pattern) {
Set<Serializable> keys = redisTemplate.keys(pattern);
if (keys.size() > 0)
redisTemplate.delete(keys);
}
/**
* 删除对应的value
*
* @param key
*/
public void remove(final String key) {
if (exists(key)) {
redisTemplate.delete(key);
}
}
/**
* 判断缓存中是否有对应的value
*
* @param key
* @return
*/
public boolean exists(final String key) {
return redisTemplate.hasKey(key);
}
/**
* 读取缓存
*
* @param key
* @return
*/
public Object get(final String key) {
Object result = null;
ValueOperations<Serializable, Object> operations = redisTemplate.opsForValue();
result = operations.get(key);
return result;
}
/**
* 哈希 添加
* hash 一个键值(key->value)对集合
*
* @param key
* @param hashKey
* @param value
*/
public void hmSet(String key, Object hashKey, Object value) {
HashOperations<String, Object, Object> hash = redisTemplate.opsForHash();
hash.put(key, hashKey, value);
}
/**
* Hash获取数据
*
* @param key
* @param hashKey
* @return
*/
public Object hmGet(String key, Object hashKey) {
HashOperations<String, Object, Object> hash = redisTemplate.opsForHash();
return hash.get(key, hashKey);
}
/**
* 列表添加
* list:lpush key value1
*
* @param k
* @param v
*/
public void lPush(String k, Object v) {
ListOperations<String, Object> list = redisTemplate.opsForList();
list.rightPush(k, v);
}
/**
* 列表List获取
* lrange： key 0 10 (读取的个数 从0开始 读取到下标为10 的数据)
*
* @param k
* @param l
* @param l1
* @return
*/
public List<Object> lRange(String k, long l, long l1) {
ListOperations<String, Object> list = redisTemplate.opsForList();
return list.range(k, l, l1);
}
/**
* Set集合添加
*
* @param key
* @param value
*/
public void add(String key, Object value) {
SetOperations<String, Object> set = redisTemplate.opsForSet();
set.add(key, value);
}
/**
* Set 集合获取
*
* @param key
* @return
*/
public Set<Object> setMembers(String key) {
SetOperations<String, Object> set = redisTemplate.opsForSet();
return set.members(key);
}
/**
* Sorted set :有序集合添加
*
* @param key
* @param value
* @param scoure
*/
public void zAdd(String key, Object value, double scoure) {
ZSetOperations<String, Object> zset = redisTemplate.opsForZSet();
zset.add(key, value, scoure);
}
/**
* Sorted set:有序集合获取
*
* @param key
* @param scoure
* @param scoure1
* @return
*/
public Set<Object> rangeByScore(String key, double scoure, double scoure1) {
ZSetOperations<String, Object> zset = redisTemplate.opsForZSet();
return zset.rangeByScore(key, scoure, scoure1);
}
/**
* 根据key获取Set中的所有值
*
* @param key 键
* @return
*/
public Set<Integer> sGet(String key) {
try {
return redisTemplate.opsForSet().members(key);
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
/**
* 根据value从一个set中查询,是否存在
*
* @param key 键
* @param value 值
* @return true 存在 false不存在
*/
public boolean sHasKey(String key, Object value) {
try {
return redisTemplate.opsForSet().isMember(key, value);
} catch (Exception e) {
e.printStackTrace();
return false;
}
}
}REDIS配置类
RedisConfig.java
import com.fasterxml.jackson.annotation.JsonAutoDetect;
import com.fasterxml.jackson.annotation.PropertyAccessor;
import com.fasterxml.jackson.databind.ObjectMapper;
import org.springframework.cache.CacheManager;
import org.springframework.cache.annotation.EnableCaching;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.cache.RedisCacheConfiguration;
import org.springframework.data.redis.cache.RedisCacheManager;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.data.redis.serializer.Jackson2JsonRedisSerializer;
import org.springframework.data.redis.serializer.RedisSerializationContext;
import org.springframework.data.redis.serializer.StringRedisSerializer;
import static org.springframework.data.redis.cache.RedisCacheConfiguration.defaultCacheConfig;
/**
* @Author: JCccc
* @CreateTime: 2018-09-11
* @Description:
*/
@Configuration
@EnableCaching
public class RedisConfig {
@Bean
public CacheManager cacheManager(RedisConnectionFactory connectionFactory) {
RedisCacheConfiguration cacheConfiguration =
defaultCacheConfig()
.disableCachingNullValues()
.serializeValuesWith(RedisSerializationContext.SerializationPair.fromSerializer(new Jackson2JsonRedisSerializer(Object.class)));
return RedisCacheManager.builder(connectionFactory).cacheDefaults(cacheConfiguration).build();
}
@Bean
public RedisTemplate<String, Object> redisTemplate(RedisConnectionFactory factory) {
RedisTemplate<String, Object> redisTemplate = new RedisTemplate<>();
redisTemplate.setConnectionFactory(factory);
Jackson2JsonRedisSerializer jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer(Object.class);
ObjectMapper om = new ObjectMapper();
om.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);
om.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL);
jackson2JsonRedisSerializer.setObjectMapper(om);
//序列化设置 ，这样为了存储操作对象时正常显示的数据，也能正常存储和获取
redisTemplate.setKeySerializer(new StringRedisSerializer());
redisTemplate.setValueSerializer(jackson2JsonRedisSerializer);
redisTemplate.setHashKeySerializer(new StringRedisSerializer());
redisTemplate.setHashValueSerializer(jackson2JsonRedisSerializer);
return redisTemplate;
}
@Bean
public StringRedisTemplate stringRedisTemplate(RedisConnectionFactory factory) {
StringRedisTemplate stringRedisTemplate = new StringRedisTemplate();
stringRedisTemplate.setConnectionFactory(factory);
return stringRedisTemplate;
}
}最后写测试接口，看看效果（一个POST，一个GET）：
故意把时间放大，1000秒内重复调用，符合我们拦截规则的都会被拦截。
TestController.java
import com.example.repeatdemo.dto.PayOrderApply;
import com.example.repeatdemo.annotation.RepeatDaMie;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.web.bind.annotation.*;
/**
* @Author: JCccc
* @Date: 2022-6-05 9:44
* @Description:
*/
@RestController
public class TestController {
private final Logger log = LoggerFactory.getLogger(this.getClass());
@RepeatDaMie(second = 1000,describe = "尊敬的客户,您慢点")
@PostMapping(value = "/doPost")
@ResponseBody
public void test(@RequestBody PayOrderApply payOrderApply) {
log.info("Controller POST请求:"+payOrderApply.toString());
}
@RepeatDaMie(second = 1000,describe = "大哥,你冷静点")
@GetMapping(value = "/doGet")
@ResponseBody
public void doGet( PayOrderApply payOrderApply) {
log.info("Controller GET请求:"+payOrderApply.toString());
}
}PayOrderApply.java
/**
* @Author: JCccc
* @Date: 2022-6-12 9:46
* @Description:
*/
public class PayOrderApply {
private String sn;
private Long amount;
private String proCode;
public String getSn() {
return sn;
}
public void setSn(String sn) {
this.sn = sn;
}
public Long getAmount() {
return amount;
}
public void setAmount(Long amount) {
this.amount = amount;
}
public String getProCode() {
return proCode;
}
public void setProCode(String proCode) {
this.proCode = proCode;
}
@Override
public String toString() {
return "PayOrderApply{" +
"sn='" + sn + '\'' +
", amount=" + amount +
", proCode='" + proCode + '\'' +
'}';
}
}
redis生成了值：
