java -version In Bash Script. Giving integer error

Question

I am trying to make this if..fi case work for the Java Version from wrapper.conf configuration file./ and from the system, If the output from wrapper.conf is java

I would have two options;
1. wrapper.java.command=/apps/jdk1.8.0_191/bin/java
2. wrapper.java.command=java

If it's long one with Java Version it should just print it.

If it's just java, which means it's using default java, and should check the java -version.

With Below script, I am failing to get it. I am getting below error.

integer expression expected Usage: java [-options] class [args...] (to execute a class) or java [-options] -jar jarfile [args...] (to execute a jar file) 

Script Snippet:

for file in $(echo $folder/conf/wrapper.conf) do JavaVersion=$(grep "command" $file | awk -F "=" '{print $NF}') if [ "$JavaVersion" -eq "java" ]; then java -version 2>&1 >/dev/null | grep 'java version' else $JavaVersion fi 

Answer 1

Besides the missing done for your loop that fra-san commented on and the -eqinteger comparison complaining about the strings you asked it to compare, there's also the error where you called some particular java binary with no parameters, generating the second half of the error you saw.

Since you're likely wanting the java version in either case, simply execute $JavaVersion regardless.

JavaVersion=$(grep wrapper.java.command= "$file" | awk -F "=" '{print $NF}') "$JavaVersion" -version 

Appears I misunderstood the end goal of printing the wrapper.java.command value if it's not exactly java, otherwise executing java -version.

if grep -Fxq wrapper.java.command=java "$file" then java -version 2>&1 | grep 'java version' else grep ^wrapper.java.command= "$file" | cut -d= -f2- fi 

Answer 2

The -eq operator is for integer comparison. Since you are trying to compare strings you will need to use =, specifically:

if [ "$JavaVersion" = "java" ]; then 

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Additionally, the following line seems flawed:

java -version 2>&1 >/dev/null | grep 'java version' 

You are redirecting both stdout and stderr to /dev/null (all output) so there will be nothing left to grep.