查看配置

		
root@netkiller ~/ops (master) [SIGINT]# alternatives --list
libnssckbi.so.x86_64  	auto  	/usr/lib64/pkcs11/p11-kit-trust.so
soelim                	auto  	/usr/bin/soelim.groff
iptables              	auto  	/usr/sbin/iptables-nft
ebtables              	auto  	/usr/sbin/ebtables-nft
arptables             	auto  	/usr/sbin/arptables-nft
cifs-idmap-plugin     	auto  	/usr/lib64/cifs-utils/cifs_idmap_sss.so
man                   	auto  	/usr/bin/man.man-db
man.7.gz              	manual	/usr/share/man/man7/man.man-pages.7.gz
nc                    	auto  	/usr/bin/ncat
ld                    	auto  	/usr/bin/ld.bfd
mvn                   	auto  	/usr/share/maven/bin/mvn
gradle                	auto  	/srv/gradle-7.5.1/bin/gradle
java                  	manual	/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.362.b09-2.el9_1.x86_64/jre/bin/java
jre_openjdk           	auto  	/usr/lib/jvm/java-11-openjdk-11.0.18.0.10-2.el9_1.x86_64
jre_11                	auto  	/usr/lib/jvm/java-11-openjdk-11.0.18.0.10-2.el9_1.x86_64
jre_11_openjdk        	auto  	/usr/lib/jvm/jre-11-openjdk-11.0.18.0.10-2.el9_1.x86_64
jre_1.8.0             	auto  	/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.362.b09-2.el9_1.x86_64/jre
jre_1.8.0_openjdk     	auto  	/usr/lib/jvm/jre-1.8.0-openjdk-1.8.0.362.b09-2.el9_1.x86_64
javac                 	manual	/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.362.b09-2.el9_1.x86_64/bin/javac
java_sdk_openjdk      	auto  	/usr/lib/jvm/java-11-openjdk-11.0.18.0.10-2.el9_1.x86_64
java_sdk_11           	auto  	/usr/lib/jvm/java-11-openjdk-11.0.18.0.10-2.el9_1.x86_64
java_sdk_11_openjdk   	auto  	/usr/lib/jvm/java-11-openjdk-11.0.18.0.10-2.el9_1.x86_64
java_sdk_1.8.0        	auto  	/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.362.b09-2.el9_1.x86_64
java_sdk_1.8.0_openjdk	auto  	/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.362.b09-2.el9_1.x86_64		
		
		

java 切换

		
root@netkiller ~/ops (master)# alternatives --config java

There are 2 programs which provide 'java'.

  Selection    Command
-----------------------------------------------
*  1           java-11-openjdk.x86_64 (/usr/lib/jvm/java-11-openjdk-11.0.18.0.10-2.el9_1.x86_64/bin/java)
 + 2           java-1.8.0-openjdk.x86_64 (/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.362.b09-2.el9_1.x86_64/jre/bin/java)

Enter to keep the current selection[+], or type selection number:		
		
		

javac 切换

		
root@netkiller ~/ops (master)# alternatives --config javac