/usr/bin/java -> /etc/alternatives/java

[root@localhost eclipse]# which java 

 /usr/bin/java 

 [root@localhost eclipse]# ls -l /usr/bin/java 

 lrwxrwxrwx 1 root root 22 Aug  1  2012 /usr/bin/java -> /etc/alternatives/java 

 [root@localhost eclipse]# ls /etc/alternatives/ 

 antlr                   jre_1.4.2_exports  print-cancelman 

 etags                   jre_exports        print-lp 

 jar                     jre_gcj            print-lpc 

 jarsigner               jre_gcj_exports    print-lpcman 

 java                    jsp                print-lpman 

 javac                   keytool            print-lpq 

 javadoc                 mta                print-lpqman 

 javah                   mta-aliasesman     print-lprm 

 java_sdk                mta-mailq          print-lprman 

 java_sdk_1.4.2          mta-mailqman       print-lprmman 

 java_sdk_1.4.2_exports  mta-newaliases     print-lpstat 

 java_sdk_exports        mta-newaliasesman  print-lpstatman 

 java_sdk_gcj            mta-pam            rmic 

 java_sdk_gcj_exports    mta-rmail          rmiregistry 

 jaxp_parser_impl        mta-sendmail       servlet 

 jaxp_transform_impl     mta-sendmailman    xinputrc 

 jre                     print 

 jre_1.4.2               print-cancel