Bash 命令检查 Linux 上是否安装了 Oracle 或 OpenJDK java 版本

Question

I need a bash line to check if java version currently installed is Oracle's or OpenJDK.

A one-liner by parsing the output of the java -version command:

java -version

java Oracle output:

java version "1.7.0_80"
Java(TM) SE Runtime Environment (build 1.7.0_80-b15)
Java HotSpot(TM) 64-Bit Server VM (build 24.80-b11, mixed mode)

java OpenJDK Output:

java version "1.7.0_91"
OpenJDK Runtime Environment (amzn-2.6.2.2.63.amzn1-x86_64 u91-b00)
OpenJDK 64-Bit Server VM (build 24.91-b01, mixed mode)

Answer 1

if [[ $(java -version 2>&1) == *"OpenJDK"* ]]; then echo ok; else echo 'not ok'; fi

Answer 2

java -version 2>&1 | grep "OpenJDK Runtime" | wc -l

returns 0 if using Oracle JDK, 1 if using OpenJDK

Bash condition:

if [[ $(java -version 2>&1 | grep "OpenJDK Runtime") ]]

Answer 3

You can use below shell script for you work:

#!/bin/bash

declare -a JAVA=($(sudo find / -name java | grep -v grep | grep "/bin/java"))

for javapath in "${JAVA[@]}"
do 
 if [[ $(sudo  ${javapath} -version 2>&1) != *"OpenJDK"* ]]; then 
    export JAVAVER=$(${javapath} -version 2>&1);
    echo "Java Location -- ${javapath}"
    echo "${JAVAVER}"

 fi
done

NOTE: This will cover all java executable files running on you hosts.