rpm -qa | grep java

rpm -e --nodeps java-1.7.0-openjdk-1.7.0.171-2.6.13.2.el7.x86_64

rpm -e --nodeps java-1.8.0-openjdk-1.8.0.161-2.b14.el7.x86_64

cd /usr/local/
mkdir java

tar -zxvf jdk-8u161-linux-x64.tar.gz -C /usr/local/java/

vim /etc/profile

#set java environment
JAVA_HOME=/usr/local/java/jdk1.8.0_161
JRE_HOME=$JAVA_HOME/jre
CLASS_PATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar:$JRE_HOME/lib/rt.jar
PATH=$PATH:$JAVA_HOME/bin:$JRE_HOME/bin
export JAVA_HOME JRE_HOME CLASS_PATH PATH

source /etc/profile

java -version

[root@localhost mysoft]# java -version
java version "1.8.0_161"
Java(TM) SE Runtime Environment (build 1.8.0_161-b12)
Java HotSpot(TM) 64-Bit Server VM (build 25.161-b12, mixed mode)