1、 Anomic FTP Server : http://www.anomic.de/AnomicFTPServer : A free FTP Server implemented in Java(not an open source tool);
2、 Apache ActiveMQ : http://activemq.apache.org : An Apache open source message broker implementationwith full support for JMS 1.1;
3、 Apache Directory Server : http://directory.apache.org : An Apache open source LDAP server written in Java and fully LDAP v3-compliant;
4、 Apache Directory Studio : http://directory.apache.org : An Apache open source LDAP browser written in Java;
5、 Apache James : http://james.apache.org/ : An Apache open source SMTP,POP3, and NNTP server written in Java;
6、 Apache OpenEJB : http://openejb.apache.org/ : An Apache open source EJB implementation with support for EJB 3.0, 2.1, 2.0, and 1.1;
7、 eXist : http://exist.sourceforge.net/ : An open source native XML database;
8、 HSQLDB : http://www.hsqldb.org/ : An open source 100% Java database;
9、 Mule : http://www.mulesource.org : A Java-based ESB implementation;