手动解压JDK压缩包，然后设置环境变量1.在/usr/目录下创建java目录[root@localhost~]#mkdir/usr/java[root@localhost~]#光盘/usr/java2.上传jdk，然后解压[root@localhostjava]#tar-zxvfjdk-8u221-linux-x64.tar.gz3。设置环境变量[root@localhostjava]#vi/etc/profile在profile中添加以下内容：#setjavaenvironmentexportJAVA_HOME=/usr/java/jdk1.8.0_221exportJRE_HOME=/usr/java/jdk1.8.0_221/jreexportPATH=$JAVA_HOME/bin:$PATHexportCLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar让修改生效：[root@localhostjava]#source/etc/profile4.验证JDK合法性[root@localhostjava]#java-version
