DefaultPreparedStatement启动Tomcat时不可序列化
问题描述：
我使用Cassandra 3.10，Datastax驱动程序3.1.4和Apache Lucerne索引生成器和Spring 4.3.2构建一个webapp以在Tomcat 7.0.57中运行。 我准备所有我用预处理的成弹簧的Singleton StatementFactory像：DefaultPreparedStatement启动Tomcat时不可序列化
selectLikeShortnameStmt = cassandraDatasource.getSession().prepare(" select id, parent_id, ultimate_parent_id, internal_ref, short_name, long_name, controlling_team, " +
" country_incorp, country_operate, company_reg, relationship_manager, credit_rating, rating_source, pd, lgd, review_date, sector, defaulted, own_bank_entity " +
" from counterparty where short_name like ?");
和
selectByReviewDateAndRmQuery = " select id, parent_id, ultimate_parent_id, internal_ref, short_name, long_name, controlling_team, " +
" country_incorp, country_operate, company_reg, relationship_manager, credit_rating, rating_source, pd, lgd, review_date, sector, defaulted, own_bank_entity " +
" from counterparty where filter_column = '{ "
+ " filter : {type:\"range\", field:\"review_date\", lower:\"01-01-2000\", upper: \"%s\" },"
+ " query : {type:\"contains\", field:\"relationship_manager\", values:[ \"%s\" ]},"
+ " refresh:true"
+ " }'";
在第一示例中，可以使用简单的BIND方法，但对于第二实施例中，绑定方法的状态没有定义绑定变量，所以我使用String.format方法，但是当我启动Tomcat时，出现错误，指出DefaultPreparedStatement不可序列化：
Caused by: java.io.NotSerializableException: com.datastax.driver.core.DefaultPreparedStatement
at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1184)
at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1548)
at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1509)
at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:348)
at java.util.HashMap.internalWriteEntries(HashMap.java:1785)
at java.util.HashMap.writeObject(HashMap.java:1362)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:1028)
at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1496)
at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1548)
at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1509)
at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1548)
at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1509)
at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1548)
at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1509)
at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1548)
at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1509)
at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1548)
at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1509)
at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:348)
at java.util.HashMap.internalWriteEntries(HashMap.java:1785)
at java.util.HashMap.writeObject(HashMap.java:1362)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:1028)
at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1496)
at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:348)
at java.util.LinkedHashMap.internalWriteEntries(LinkedHashMap.java:333)
at java.util.HashMap.writeObject(HashMap.java:1362)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:1028)
at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1496)
at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1548)
at java.io.ObjectOutputStream.defaultWriteObject(ObjectOutputStream.java:441)
at java.util.Collections$SynchronizedMap.writeObject(Collections.java:2691)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:1028)
at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1496)
at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:348)
at org.apache.catalina.session.StandardSession.writeObject(StandardSession.java:1695)
at org.apache.catalina.session.StandardSession.writeObjectData(StandardSession.java:1101)
at org.apache.catalina.session.StandardManager.doUnload(StandardManager.java:430)
at org.apache.catalina.session.StandardManager.unload(StandardManager.java:351)
at org.apache.catalina.session.StandardManager.stopInternal(StandardManager.java:516)
at org.apache.catalina.util.LifecycleBase.stop(LifecycleBase.java:232)
at org.apache.catalina.core.StandardContext.stopInternal(StandardContext.java:5683)
at org.apache.catalina.util.LifecycleBase.stop(LifecycleBase.java:232)
at org.apache.catalina.core.ContainerBase$StopChild.call(ContainerBase.java:1591)
at org.apache.catalina.core.ContainerBase$StopChild.call(ContainerBase.java:1580)
... 4 more
虽然代码根本不使用DefaultPreparedStatement。
在DAO对象，这些都是例子：
PreparedStatement pStmt = statementFactory.getSelectLikeShortnameStmt();
BoundStatement bStmt = pStmt.bind("%" + name + "%");
ResultSet rs = cassandraDatasource.getSession().execute(bStmt);
和
String query = statementFactory.getSelectByReviewDateAndTeamQuery();
query = String.format(query, upperDate, controllingTeamCode);
ResultSet rs = cassandraDatasource.getSession().execute(query);
答
由于DefaultPreparedStatement是实现该接口的PreparedStatement唯一的类，它没有实现Serializable接口似乎有除了在Tomcat中禁用会话持久性之外没有别的选择，这可以通过编辑tomcat conf目录中的context.xml来实现
为了缩小字段，我重写了代码，以便所有DAO对象都像第一个示例中那样使用PreparedStatement结构，而不像第二个示例中那样使用查询字符串，但它没有区别。查看javadoc，DefaultPreparedStatement是实现PreparedStatement接口的唯一类，但没有提到它是可序列化的。 – simteq