content: package org.jeecg.common.modules.redis.writer;
  
  import java.nio.charset.StandardCharsets;
  import java.time.Duration;
  import java.util.Collections;
  import java.util.Optional;
  import java.util.Set;
  import java.util.concurrent.TimeUnit;
  import java.util.function.Consumer;
  import java.util.function.Function;
  
  import lombok.extern.slf4j.Slf4j;
  import org.springframework.dao.PessimisticLockingFailureException;
  import org.springframework.data.redis.cache.RedisCacheWriter;
  import org.springframework.data.redis.connection.RedisConnection;
  import org.springframework.data.redis.connection.RedisConnectionFactory;
  import org.springframework.data.redis.connection.RedisStringCommands.SetOption;
  import org.springframework.data.redis.core.types.Expiration;
  import org.springframework.lang.Nullable;
  import org.springframework.util.Assert;
  
  /**
   * 该类参照 DefaultRedisCacheWriter 重写了 remove 方法实现通配符*删除
   */
  @Slf4j
  public class JeecgRedisCacheWriter implements RedisCacheWriter {
  
      private final RedisConnectionFactory connectionFactory;
      private final Duration sleepTime;
  
      public JeecgRedisCacheWriter(RedisConnectionFactory connectionFactory) {
          this(connectionFactory, Duration.ZERO);
      }
  
      public JeecgRedisCacheWriter(RedisConnectionFactory connectionFactory, Duration sleepTime) {
          Assert.notNull(connectionFactory, "ConnectionFactory must not be null!");
          Assert.notNull(sleepTime, "SleepTime must not be null!");
          this.connectionFactory = connectionFactory;
          this.sleepTime = sleepTime;
      }
  
      public void put(String name, byte[] key, byte[] value, @Nullable Duration ttl) {
          Assert.notNull(name, "Name must not be null!");
          Assert.notNull(key, "Key must not be null!");
          Assert.notNull(value, "Value must not be null!");
          this.execute(name, (connection) -> {
              if (shouldExpireWithin(ttl)) {
                  connection.set(key, value, Expiration.from(ttl.toMillis(), TimeUnit.MILLISECONDS), SetOption.upsert());
              } else {
                  connection.set(key, value);
              }
  
              return "OK";
          });
      }
  
      public byte[] get(String name, byte[] key) {
          Assert.notNull(name, "Name must not be null!");
          Assert.notNull(key, "Key must not be null!");
          return (byte[])this.execute(name, (connection) -> {
              return connection.get(key);
          });
      }
  
      public byte[] putIfAbsent(String name, byte[] key, byte[] value, @Nullable Duration ttl) {
          Assert.notNull(name, "Name must not be null!");
          Assert.notNull(key, "Key must not be null!");
          Assert.notNull(value, "Value must not be null!");
          return (byte[])this.execute(name, (connection) -> {
              if (this.isLockingCacheWriter()) {
                  this.doLock(name, connection);
              }
  
              Object var7;
              try {
                  boolean put;
                  if (shouldExpireWithin(ttl)) {
                      put = connection.set(key, value, Expiration.from(ttl), SetOption.ifAbsent());
                  } else {
                      put = connection.setNX(key, value);
                  }
  
                  if (!put) {
                      byte[] var11 = connection.get(key);
                      return var11;
                  }
  
                  var7 = null;
              } finally {
                  if (this.isLockingCacheWriter()) {
                      this.doUnlock(name, connection);
                  }
  
              }
  
              return (byte[])var7;
          });
      }
  
      public void remove(String name, byte[] key) {
          Assert.notNull(name, "Name must not be null!");
          Assert.notNull(key, "Key must not be null!");
          String keyString = new String(key);
          log.info("redis remove key:" + keyString);
          if(keyString!=null && keyString.endsWith("*")){
              execute(name, connection -> {
                  // 获取某个前缀所拥有的所有的键，某个前缀开头，后面肯定是*
                  Set<byte[]> keys = connection.keys(key);
                  int delNum = 0;
                  for (byte[] keyByte : keys) {
                      delNum += connection.del(keyByte);
                  }
                  return delNum;
              });
          }else{
              this.execute(name, (connection) -> {
                  return connection.del(new byte[][]{key});
              });
          }
      }
  
      public void clean(String name, byte[] pattern) {
          Assert.notNull(name, "Name must not be null!");
          Assert.notNull(pattern, "Pattern must not be null!");
          this.execute(name, (connection) -> {
              boolean wasLocked = false;
  
              try {
                  if (this.isLockingCacheWriter()) {
                      this.doLock(name, connection);
                      wasLocked = true;
                  }
  
                  byte[][] keys = (byte[][])((Set)Optional.ofNullable(connection.keys(pattern)).orElse(Collections.emptySet())).toArray(new byte[0][]);
                  if (keys.length > 0) {
                      connection.del(keys);
                  }
              } finally {
                  if (wasLocked && this.isLockingCacheWriter()) {
                      this.doUnlock(name, connection);
                  }
  
              }
  
              return "OK";
          });
      }
  
      void lock(String name) {
          this.execute(name, (connection) -> {
              return this.doLock(name, connection);
          });
      }
  
      void unlock(String name) {
          this.executeLockFree((connection) -> {
              this.doUnlock(name, connection);
          });
      }
  
      private Boolean doLock(String name, RedisConnection connection) {
          return connection.setNX(createCacheLockKey(name), new byte[0]);
      }
  
      private Long doUnlock(String name, RedisConnection connection) {
          return connection.del(new byte[][]{createCacheLockKey(name)});
      }
  
      boolean doCheckLock(String name, RedisConnection connection) {
          return connection.exists(createCacheLockKey(name));
      }
  
      private boolean isLockingCacheWriter() {
          return !this.sleepTime.isZero() && !this.sleepTime.isNegative();
      }
  
      private <T> T execute(String name, Function<RedisConnection, T> callback) {
          RedisConnection connection = this.connectionFactory.getConnection();
  
          try {
              this.checkAndPotentiallyWaitUntilUnlocked(name, connection);
              return callback.apply(connection);
          } finally {
              connection.close();
          }
  
      }
  
      private void executeLockFree(Consumer<RedisConnection> callback) {
          RedisConnection connection = this.connectionFactory.getConnection();
  
          try {
              callback.accept(connection);
          } finally {
              connection.close();
          }
  
      }
  
      private void checkAndPotentiallyWaitUntilUnlocked(String name, RedisConnection connection) {
          if (this.isLockingCacheWriter()) {
              try {
                  while(this.doCheckLock(name, connection)) {
                      Thread.sleep(this.sleepTime.toMillis());
                  }
  
              } catch (InterruptedException var4) {
                  Thread.currentThread().interrupt();
                  throw new PessimisticLockingFailureException(String.format("Interrupted while waiting to unlock cache %s", name), var4);
              }
          }
      }
  
      private static boolean shouldExpireWithin(@Nullable Duration ttl) {
          return ttl != null && !ttl.isZero() && !ttl.isNegative();
      }
  
      private static byte[] createCacheLockKey(String name) {
          return (name + "~lock").getBytes(StandardCharsets.UTF_8);
      }
  }
  