使用postgres-xc报错Unsupported binary encoding of timestamp

项目中使用了Postgres-XC作为关系型数据库，而应用则是部署在IBM WAS中，在WAS控制台的配置了基于postgresql-9.3-1103.jdbc4.jar的数据源，但发现一个问题，某个读取包含timestamp类型字段的查询在创建连接后前几次执行不会报错，但后续的执行就会报错。

Caused by: org.postgresql.util.PSQLException: Unsupported binary encoding of timestamp.
        at org.postgresql.jdbc2.TimestampUtils.toTimestampBin(TimestampUtils.java:727)
        at org.postgresql.jdbc2.AbstractJdbc2ResultSet.getTimestamp(AbstractJdbc2ResultSet.java:517)
        at org.postgresql.jdbc2.AbstractJdbc2ResultSet.getTimestamp(AbstractJdbc2ResultSet.java:2629)
        at com.ibm.ws.rsadapter.jdbc.WSJdbcResultSet.getTimestamp(WSJdbcResultSet.java:2672)
        at org.hibernate.type.descriptor.sql.TimestampTypeDescriptor$2.doExtract(TimestampTypeDescriptor.java:62)
        at org.hibernate.type.descriptor.sql.BasicExtractor.extract(BasicExtractor.java:64)
        at org.hibernate.type.AbstractStandardBasicType.nullSafeGet(AbstractStandardBasicType.java:254)
        at org.hibernate.type.AbstractStandardBasicType.nullSafeGet(AbstractStandardBasicType.java:250)
        at org.hibernate.type.AbstractStandardBasicType.nullSafeGet(AbstractStandardBasicType.java:230)
        at org.hibernate.type.AbstractStandardBasicType.hydrate(AbstractStandardBasicType.java:331)
        at org.hibernate.persister.entity.AbstractEntityPersister.hydrate(AbstractEntityPersister.java:2283)
        at org.hibernate.loader.Loader.loadFromResultSet(Loader.java:1527)
        at org.hibernate.loader.Loader.instanceNotYetLoaded(Loader.java:1455)
        at org.hibernate.loader.Loader.getRow(Loader.java:1355)
        at org.hibernate.loader.Loader.getRowFromResultSet(Loader.java:611)
        at org.hibernate.loader.Loader.doQuery(Loader.java:829)
        at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:274)
        at org.hibernate.loader.Loader.doList(Loader.java:2542)
        ... 82 more

查看postgresql jdbc源码可以看到报错的那段代码。

    /**
     * Returns the SQL Timestamp object matching the given bytes with
     * {@link Oid#TIMESTAMP} or {@link Oid#TIMESTAMPTZ}.
     * 
     * @param tz The timezone used when received data is {@link Oid#TIMESTAMP},
     * ignored if data already contains {@link Oid#TIMESTAMPTZ}.
     * @param bytes The binary encoded timestamp value.
     * @param timestamptz True if the binary is in GMT.
     * @return The parsed timestamp object.
     * @throws PSQLException If binary format could not be parsed.
     */
    public Timestamp toTimestampBin(TimeZone tz, byte[] bytes, boolean timestamptz)
        throws PSQLException {
        
        if (bytes.length != 8) {
            throw new PSQLException(GT.tr("Unsupported binary encoding of {0}.",
                    "timestamp"), PSQLState.BAD_DATETIME_FORMAT);
        } 

可以看到得到的是以二进制编码的时间值，在jdbc代码中将其转化为Java中的Timestamp类型，而报错的原因是二进制编码的时间值存在问题。是WAS的问题？还是hibernate的问题？还是postgresql-jdbc的问题？还是postgres-xc的问题？

查看网络资料，发现postgresql-jdbc有两种传输数据的方式，一种是字符串，一种是二进制。使用二进制传输可以减少网络传输所需的字节数，进而提高效率。同时，在postgresql-jdbc中有相对应的配置，所以，如果二进制传输出错，是否可以尝试一下传统的字符串传输呢？