open-nomad/drivers/java/utils.go
2018-11-06 12:41:39 -08:00

45 lines
1 KiB
Go

package java
import (
"bytes"
"fmt"
"os/exec"
"regexp"
"strings"
)
var javaVersionCommand = []string{"java", "-version"}
func javaVersionInfo() (version, runtime, vm string, err error) {
var out bytes.Buffer
cmd := exec.Command(javaVersionCommand[0], javaVersionCommand[1:]...)
cmd.Stdout = &out
cmd.Stderr = &out
err = cmd.Run()
if err != nil {
return
}
version, runtime, vm, err = parseJavaVersionOutput(out.String())
return
}
func parseJavaVersionOutput(infoString string) (version, runtime, vm string, err error) {
infoString = strings.TrimSpace(infoString)
lines := strings.Split(infoString, "\n")
if len(lines) != 3 {
return "", "", "", fmt.Errorf("unexpected java version info output, expected 3 lines but got: %v", infoString)
}
versionString := strings.TrimSpace(lines[0])
re := regexp.MustCompile(`version "([^"]*)"`)
if match := re.FindStringSubmatch(lines[0]); len(match) == 2 {
versionString = match[1]
}
return versionString, strings.TrimSpace(lines[1]), strings.TrimSpace(lines[2]), nil
}