Caused by: com.mysql.jdbc.exceptions.MySQLIntegrityConstraintViolationException

[Suraj Savaratkar]

I am Implementing a ModelDriven interface with its getModel() mehtod in Action class and passing an object of an bean(POJO) class
to save the bean object into DAO class with passing this object to method but it thrown an Exception like that



Caused by: com.mysql.jdbc.exceptions.MySQLIntegrityConstraintViolationException: Cannot add or update a child row:
a foreign key constraint fails (`changedftts/capabilitybuilding`, CONSTRAINT `FK_capabilitybuilding_2` FOREIGN KEY (`mentorID`)
REFERENCES `mentor` (`mentorID`) ON DELETE CASCADE ON UPDATE CASCADE)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1011)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:956)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3515)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3447)
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1951)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2101)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2554)
at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:1761)
at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:2046)
at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:1964)
at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:1949)
at org.hibernate.persister.entity.BasicEntityPersister.insert(BasicEntityPersister.java:1729)

what is reason for thrown an 'MySQLIntegrityConstraintViolationException'.