Question

Is it supposedly possible for java.sql.Statement.execute to throw java.io.EOFException?

In http://docs.oracle.com/javase/7/docs/api/java/sql/Statement.html#execute%28java.lang.String,%20int%29 it is said that it may throw only java.sql.SQLException. However, I got this exception message logged:

** BEGIN NESTED EXCEPTION **

java.io.EOFException

STACKTRACE:

java.io.EOFException
        at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:1394)
        at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:1538)
        at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:1929)
        at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1167)
        at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:1278)
        at com.mysql.jdbc.MysqlIO.sqlQuery(MysqlIO.java:1224)
        at com.mysql.jdbc.Connection.execSQL(Connection.java:2244)
        at com.mysql.jdbc.Connection.execSQL(Connection.java:2192)
        at com.mysql.jdbc.Statement.execute(Statement.java:906)
        at com.mysql.jdbc.Statement.execute(Statement.java:947)
        at sun.reflect.GeneratedMethodAccessor8.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:597)
        at org.logicalcobwebs.proxool.ProxyStatement.invoke(ProxyStatement.java:100)
        at org.logicalcobwebs.proxool.ProxyStatement.intercept(ProxyStatement.java:57)
        at $java.sql.Statement$$EnhancerByCGLIB$$4e952ca0.execute()
        at handler.do_insert(handler.java:734)

On line 733 of “handler.java” there is the “execute” call, and on 734 there is a call to getGeneratedKeys (which also may throw only SQLException).

Answer 1

Look for the words ** BEGIN NESTED EXCEPTION **. This exception is not thrown by execute(), it’s a nested exception. That means that is was passed as the cause when creating the SQLException. Something like this:

try {

    ...

} catch (EOFException e) {
    throw new SQLException(e);
}