java - Check if database is available before job in spring batch -


my question how check if database available before starting job in spring batch.

i tried create new class implements jobexecutionlistener, , call method beforejob. problem how test, because database configuration in database-context.xml?

database-context.xml:

<beans xmlns="http://www.springframework.org/schema/beans"     xmlns:batch="http://www.springframework.org/schema/batch" xmlns:xsi="http://www.w3.org/2001/xmlschema-instance"     xsi:schemalocation="http://www.springframework.org/schema/beans          http://www.springframework.org/schema/beans/spring-beans-4.0.xsd">      <bean id="datasource" class="org.springframework.jdbc.datasource.drivermanagerdatasource">         <property name="driverclassname" value="com.mysql.jdbc.driver" />         <property name="url" value="jdbc:mysql://localhost:3306/mydb_3" />         <property name="username" value="root" />         <property name="password" value="" />     </bean> </beans>

for example, when put mydb_4 (and mydb_4 doesn't exist), following error:

error while extracting database product name - falling empty error codes org.springframework.jdbc.support.metadataaccessexception: not connection extracting meta data; nested exception org.springframework.jdbc.cannotgetjdbcconnectionexception: not jdbc connection; nested exception com.mysql.jdbc.exceptions.jdbc4.mysqlsyntaxerrorexception: unknown database 'mydb_4'     @ org.springframework.jdbc.support.jdbcutils.extractdatabasemetadata(jdbcutils.java:293)

now how catch error , check if database available in method created in beforejob?


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