java.lang.ClassCastException

There are no available Samebug tips for this exception. Do you have an idea how to solve this issue? A short tip would help users who saw this issue last week.

  • Link to Jedis issue reported- https://github.com/xetorthio/jedis/issues/918#issuecomment-78409511 I am using redis in a heavily multi-threaded java application and getting intermittent ClassCastExceptions I am using Jedis pool, and have verified that spring ensures the resources are returned to the pool, by calling returnResource() and returnBrokenResource in case of exceptions. Still facing this issue. I have a heavily multi-threaded environment I am using multiple spring RedisTemplates for serializing/deserializing different models. I have configured different spring RedisTemplates with their own JedisConnectionFactory so that the jedis pool is created per factory, but this didn't solve the issue. I was always using a pool, and added testOnBorrow as well as testOnReturn true, but didn't help Exception stack trace- stack - Thread 1: [ERROR] [03/01/2015 07:05:32.044] [events-system-akka.actor.default-dispatcher-2281] [akka://events-system/user/$YN/$b/$b/$b] java.lang.Long cannot be cast to java.util.List java.lang.ClassCastException: java.lang.Long cannot be cast to java.util.List at redis.clients.jedis.Connection.getRawObjectMultiBulkReply(Connection.java:230) at redis.clients.jedis.Connection.getObjectMultiBulkReply(Connection.java:236) at redis.clients.jedis.BinaryJedis.zscan(BinaryJedis.java:3608) at org.springframework.data.redis.connection.jedis.JedisConnection$3.doScan(JedisConnection.java:2998) at org.springframework.data.redis.core.KeyBoundCursor.doScan(KeyBoundCursor.java:39) at org.springframework.data.redis.core.ScanCursor.scan(ScanCursor.java:85) at org.springframework.data.redis.core.ScanCursor.hasNext(ScanCursor.java:168) at org.springframework.data.redis.core.ConvertingCursor.hasNext(ConvertingCursor.java:56) ... application specific stack trace ... Thread 2: [ERROR] [03/01/2015 07:03:07.295] [events-system-akka.actor.default-dispatcher-2273] [akka://events-system/user/$VN/$b/$b/$b] Unknown redis exception; nested exception is java.lang.ClassCastException: [B cannot be cast to java.lang.Long org.springframework.data.redis.RedisSystemException: Unknown redis exception; nested exception is java.lang.ClassCastException: [B cannot be cast to java.lang.Long at org.springframework.data.redis.FallbackExceptionTranslationStrategy.getFallback(FallbackExceptionTranslationStrategy.java:48) at org.springframework.data.redis.FallbackExceptionTranslationStrategy.translate(FallbackExceptionTranslationStrategy.java:38) at org.springframework.data.redis.connection.jedis.JedisConnection.convertJedisAccessException(JedisConnection.java:195) at org.springframework.data.redis.connection.jedis.JedisConnection.zRem(JedisConnection.java:2321) at org.springframework.data.redis.core.DefaultZSetOperations$19.doInRedis(DefaultZSetOperations.java:283) at org.springframework.data.redis.core.DefaultZSetOperations$19.doInRedis(DefaultZSetOperations.java:280) at org.springframework.data.redis.core.RedisTemplate.execute(RedisTemplate.java:190) at org.springframework.data.redis.core.RedisTemplate.execute(RedisTemplate.java:152) at org.springframework.data.redis.core.AbstractOperations.execute(AbstractOperations.java:85) at org.springframework.data.redis.core.DefaultZSetOperations.remove(DefaultZSetOperations.java:280) ... application specific stack trace ... Caused by: java.lang.ClassCastException: [B cannot be cast to java.lang.Long at redis.clients.jedis.Connection.getIntegerReply(Connection.java:210) at redis.clients.jedis.BinaryJedis.zrem(BinaryJedis.java:1624) at org.springframework.data.redis.connection.jedis.JedisConnection.zRem(JedisConnection.java:2319) ... 21 more Spring redis configuration - <bean id="jedisConnFactory" class="org.springframework.data.redis.connection.jedis.JedisConnectionFactory" redis:usePool="true" redis:poolConfig-ref="jedisPoolConfig" redis:hostName="${redis.datasource.hostName}" redis:database="${redis.database.index}" redis:port="${redis.datastore.port}"/> <bean id="jedisPoolConfig" class="redis.clients.jedis.JedisPoolConfig"> <property name="maxIdle" value="${redis.conn.maxIdle}"/> <property name="maxTotal" value="${redis.conn.maxTotal}"/> <property name="minIdle" value="${redis.conn.minIdle}"/> <property name="testOnBorrow" value="true"/> </bean> <bean id="redisTemplate" class="org.springframework.data.redis.core.RedisTemplate" redis:connectionFactory-ref="jedisConnFactory" redis:keySerializer-ref="redisStringSerializer" redis:valueSerializer-ref="redisStringSerializer" redis:defaultSerializer-ref="redisStringSerializer"/> <bean id="redisTemplate2" class="org.springframework.data.redis.core.RedisTemplate" redis:connectionFactory-ref="jedisConnFactory2" redis:keySerializer-ref="redisStringSerializer" redis:valueSerializer-ref="redisCustomDomainObjectSerializer" redis:defaultSerializer-ref="redisStringSerializer"/>
    via by Deepak Pol,
  • Link to Jedis issue reported- https://github.com/xetorthio/jedis/issues/918#issuecomment-78409511 I am using redis in a heavily multi-threaded java application and getting intermittent ClassCastExceptions I am using Jedis pool, and have verified that spring ensures the resources are returned to the pool, by calling returnResource() and returnBrokenResource in case of exceptions. Still facing this issue. I have a heavily multi-threaded environment I am using multiple spring RedisTemplates for serializing/deserializing different models. I have configured different spring RedisTemplates with their own JedisConnectionFactory so that the jedis pool is created per factory, but this didn't solve the issue. I was always using a pool, and added testOnBorrow as well as testOnReturn true, but didn't help Exception stack trace- stack - Thread 1: [ERROR] [03/01/2015 07:05:32.044] [events-system-akka.actor.default-dispatcher-2281] [akka://events-system/user/$YN/$b/$b/$b] java.lang.Long cannot be cast to java.util.List java.lang.ClassCastException: java.lang.Long cannot be cast to java.util.List at redis.clients.jedis.Connection.getRawObjectMultiBulkReply(Connection.java:230) at redis.clients.jedis.Connection.getObjectMultiBulkReply(Connection.java:236) at redis.clients.jedis.BinaryJedis.zscan(BinaryJedis.java:3608) at org.springframework.data.redis.connection.jedis.JedisConnection$3.doScan(JedisConnection.java:2998) at org.springframework.data.redis.core.KeyBoundCursor.doScan(KeyBoundCursor.java:39) at org.springframework.data.redis.core.ScanCursor.scan(ScanCursor.java:85) at org.springframework.data.redis.core.ScanCursor.hasNext(ScanCursor.java:168) at org.springframework.data.redis.core.ConvertingCursor.hasNext(ConvertingCursor.java:56) ... application specific stack trace ... Thread 2: [ERROR] [03/01/2015 07:03:07.295] [events-system-akka.actor.default-dispatcher-2273] [akka://events-system/user/$VN/$b/$b/$b] Unknown redis exception; nested exception is java.lang.ClassCastException: [B cannot be cast to java.lang.Long org.springframework.data.redis.RedisSystemException: Unknown redis exception; nested exception is java.lang.ClassCastException: [B cannot be cast to java.lang.Long at org.springframework.data.redis.FallbackExceptionTranslationStrategy.getFallback(FallbackExceptionTranslationStrategy.java:48) at org.springframework.data.redis.FallbackExceptionTranslationStrategy.translate(FallbackExceptionTranslationStrategy.java:38) at org.springframework.data.redis.connection.jedis.JedisConnection.convertJedisAccessException(JedisConnection.java:195) at org.springframework.data.redis.connection.jedis.JedisConnection.zRem(JedisConnection.java:2321) at org.springframework.data.redis.core.DefaultZSetOperations$19.doInRedis(DefaultZSetOperations.java:283) at org.springframework.data.redis.core.DefaultZSetOperations$19.doInRedis(DefaultZSetOperations.java:280) at org.springframework.data.redis.core.RedisTemplate.execute(RedisTemplate.java:190) at org.springframework.data.redis.core.RedisTemplate.execute(RedisTemplate.java:152) at org.springframework.data.redis.core.AbstractOperations.execute(AbstractOperations.java:85) at org.springframework.data.redis.core.DefaultZSetOperations.remove(DefaultZSetOperations.java:280) ... application specific stack trace ... Caused by: java.lang.ClassCastException: [B cannot be cast to java.lang.Long at redis.clients.jedis.Connection.getIntegerReply(Connection.java:210) at redis.clients.jedis.BinaryJedis.zrem(BinaryJedis.java:1624) at org.springframework.data.redis.connection.jedis.JedisConnection.zRem(JedisConnection.java:2319) ... 21 more Spring redis configuration - <bean id="jedisConnFactory" class="org.springframework.data.redis.connection.jedis.JedisConnectionFactory" redis:usePool="true" redis:poolConfig-ref="jedisPoolConfig" redis:hostName="${redis.datasource.hostName}" redis:database="${redis.database.index}" redis:port="${redis.datastore.port}"/> <bean id="jedisPoolConfig" class="redis.clients.jedis.JedisPoolConfig"> <property name="maxIdle" value="${redis.conn.maxIdle}"/> <property name="maxTotal" value="${redis.conn.maxTotal}"/> <property name="minIdle" value="${redis.conn.minIdle}"/> <property name="testOnBorrow" value="true"/> </bean> <bean id="redisTemplate" class="org.springframework.data.redis.core.RedisTemplate" redis:connectionFactory-ref="jedisConnFactory" redis:keySerializer-ref="redisStringSerializer" redis:valueSerializer-ref="redisStringSerializer" redis:defaultSerializer-ref="redisStringSerializer"/> <bean id="redisTemplate2" class="org.springframework.data.redis.core.RedisTemplate" redis:connectionFactory-ref="jedisConnFactory2" redis:keySerializer-ref="redisStringSerializer" redis:valueSerializer-ref="redisCustomDomainObjectSerializer" redis:defaultSerializer-ref="redisStringSerializer"/>
    via by Deepak Pol,
  • The concurrent use of {{SCAN}} and iteration over the resulting {{Cursor}} causes various Exceptions using the Jedis Driver. Test case: https://gist.github.com/mp911de/327cb876117bc1d74049aff25e5509cb {code} redis.clients.jedis.exceptions.JedisConnectionException: Unknown reply: 5 at redis.clients.jedis.Protocol.process(Protocol.java:154) at redis.clients.jedis.Protocol.processMultiBulkReply(Protocol.java:196) at redis.clients.jedis.Protocol.process(Protocol.java:147) at redis.clients.jedis.Protocol.processMultiBulkReply(Protocol.java:196) at redis.clients.jedis.Protocol.process(Protocol.java:147) at redis.clients.jedis.Protocol.read(Protocol.java:205) at redis.clients.jedis.Connection.readProtocolWithCheckingBroken(Connection.java:297) at redis.clients.jedis.Connection.getRawObjectMultiBulkReply(Connection.java:242) at redis.clients.jedis.Connection.getObjectMultiBulkReply(Connection.java:248) at redis.clients.jedis.BinaryJedis.hscan(BinaryJedis.java:3300) at org.springframework.data.redis.connection.jedis.JedisConnection$5.doScan(JedisConnection.java:3437) {code} {code} java.lang.ClassCastException: [B cannot be cast to java.util.List at redis.clients.jedis.Connection.getRawObjectMultiBulkReply(Connection.java:242) at redis.clients.jedis.Connection.getObjectMultiBulkReply(Connection.java:248) at redis.clients.jedis.BinaryJedis.hscan(BinaryJedis.java:3300) at org.springframework.data.redis.connection.jedis.JedisConnection$5.doScan(JedisConnection.java:3437) {code} This issue gets only visible if: 1. Multiple threads try to use the {{SCAN}} command and iterate over the resulting {{Cursor}} 2. There is enough data to keep the iteration busy The reason is that the resulting {{Cursor}} s hold a reference to the connection that was allocated during the {{.scan()}} invocation. {{.scan()}} allocates a connection but then it releases the connection back and so can multiple {{Cursors}} in different {{Thread}} s share the same Jedis connection.
    via by Mark Paluch,
    • java.lang.ClassCastException: java.lang.Long cannot be cast to java.util.List at redis.clients.jedis.Connection.getRawObjectMultiBulkReply(Connection.java:230) at redis.clients.jedis.Connection.getObjectMultiBulkReply(Connection.java:236) at redis.clients.jedis.BinaryJedis.zscan(BinaryJedis.java:3608) at org.springframework.data.redis.connection.jedis.JedisConnection$3.doScan(JedisConnection.java:2998) at org.springframework.data.redis.core.KeyBoundCursor.doScan(KeyBoundCursor.java:39) at org.springframework.data.redis.core.ScanCursor.scan(ScanCursor.java:85) at org.springframework.data.redis.core.ScanCursor.hasNext(ScanCursor.java:168) at org.springframework.data.redis.core.ConvertingCursor.hasNext(ConvertingCursor.java:56)

    Users with the same issue

    Unknown visitor
    Unknown visitor1 times, last one,
    Unknown visitor
    Unknown visitor1 times, last one,
    sriharshakiransriharshakiran
    3 times, last one,