When I try to compile commons-dbcp-1.2.2 with JDK6/7 I get this error:
org.apache.commons.dbcp.BasicDataSource is not abstract and does not override abstract method isWrapperFor(java.lang.Class) in java.sql.Wrapper
This is because commons-dbcp-1.2.2 was written before JDK6, at a time where java.sql.Wrapper
did not have an isWrapperFor
method.
So I installed JDK5, but I get such messages (probably because of all the Java7-compiled JARs):
java.lang.UnsupportedClassVersionError: Bad version number in .class file
How to solve this problem?