You can use Crystal Reports for Eclipse libraries to build custom java solutions to interact with your crystal reports if you do not have an BusinessObjects Enterprise system.
Refer to the below links
SAP Crystal Reports, version for Eclipse - Downloads
http://scn.sap.com/docs/DOC-29757
SAP Crystal Reports for Java runtime components - Java Reporting Component
http://downloads.businessobjects.com/akdlm/crystalreportsforeclipse/2_0/crjava-runtime_12.2.219.zip
Sample Codes:
http://wiki.scn.sap.com/wiki/display/BOBJ/Crystal+Reports+Java++SDK+Samples
Thanks,
Prithvi