325.15. 将正文和标头存储为文本
可从 Camel 2.11 开始
您可以配置 JdbcAggregationRepository
来存储消息正文,并在单独的列中选择(ed)标头作为 String。例如,要存储正文,以下两个标题为 companyName
和 accountName
,使用以下 SQL:
CREATE TABLE aggregationRepo3 ( id varchar(255) NOT NULL, exchange blob NOT NULL, body varchar(1000), companyName varchar(1000), accountName varchar(1000), constraint aggregationRepo3_pk PRIMARY KEY (id) ); CREATE TABLE aggregationRepo3_completed ( id varchar(255) NOT NULL, exchange blob NOT NULL, body varchar(1000), companyName varchar(1000), accountName varchar(1000), constraint aggregationRepo3_completed_pk PRIMARY KEY (id) );
CREATE TABLE aggregationRepo3 (
id varchar(255) NOT NULL,
exchange blob NOT NULL,
body varchar(1000),
companyName varchar(1000),
accountName varchar(1000),
constraint aggregationRepo3_pk PRIMARY KEY (id)
);
CREATE TABLE aggregationRepo3_completed (
id varchar(255) NOT NULL,
exchange blob NOT NULL,
body varchar(1000),
companyName varchar(1000),
accountName varchar(1000),
constraint aggregationRepo3_completed_pk PRIMARY KEY (id)
);
然后,将存储库配置为启用此行为,如下所示:
<bean id="repo3" class="org.apache.camel.processor.aggregate.jdbc.JdbcAggregationRepository"> <property name="repositoryName" value="aggregationRepo3"/> <property name="transactionManager" ref="txManager3"/> <property name="dataSource" ref="dataSource3"/> <!-- configure to store the message body and following headers as text in the repo --> <property name="storeBodyAsText" value="true"/> <property name="headersToStoreAsText"> <list> <value>companyName</value> <value>accountName</value> </list> </property> </bean>
<bean id="repo3"
class="org.apache.camel.processor.aggregate.jdbc.JdbcAggregationRepository">
<property name="repositoryName" value="aggregationRepo3"/>
<property name="transactionManager" ref="txManager3"/>
<property name="dataSource" ref="dataSource3"/>
<!-- configure to store the message body and following headers as text in the repo -->
<property name="storeBodyAsText" value="true"/>
<property name="headersToStoreAsText">
<list>
<value>companyName</value>
<value>accountName</value>
</list>
</property>
</bean>
325.15.1. codec (导航)
由于它们可以包含任何类型的有效负载,因此设计交换并不被序列化。它转换为数据库 BLOB 字段中存储的字节阵列。所有这些转换都由 JdbcCodec
类处理。代码细节需要您关注: ClassLoadingAwareObjectInputStream
。
ClassLoadingAwareObjectInputStream
已从 Apache ActiveMQ 项目中重复使用。它将打包了 ObjectInputStream
,并将其与 ContextClassLoader
而非当前Thread
一起一起使用。这样做的好处是能够加载由其他捆绑包公开的类。这允许交换正文和标头具有自定义类型对象引用。