我的软件运行时为何找不到java,用何命令配置才能找到？

adsl9999

我成功地安装了J2SE v 1.4.2_04 SDK with NetBeans 3.6 Bundle
安装在/opt/j2sdk1.4.2-04
/opt/netbeans3.6
但我的软件运行时为何找不到java（redhat9.0)
[root@localhost root]# cd azureus
[root@localhost azureus]# ./azureus
Starting Azureus...
Java exec found in PATH. Verifying...
1.3.1
OOPS, your java version is too old [java = 1.3.1]
You need to upgrade to JRE 1.4.x or newer from http://java.sun.com
ls: /usr/java: 没有那个文件或目录
OOPS, unable to locate java exec in  /usr/java/  hierarchy
You need to upgrade to JRE 1.4.x or newer from http://java.sun.com
[root@localhost azureus]#
用何命令配置才能找到？请全部详细，本人不是计算机专业，谢谢！

mozilla

export PATH=/opt/j2sdk1.4.2-04/bin:$PATH