fixes(#5439): Build should enforce a required jdk version

cmd/util/check_jdk_version/main.go

@@ -0,0 +1,49 @@
+package main
+
+import (
+	"fmt"
+	"os/exec"
+	"regexp"
+	"strconv"
+	"strings"
+)
+
+func main() {
+
+	cmd := exec.Command("mvn", "-version")
+	output, err := cmd.CombinedOutput()
+	if err != nil {
+		_ = fmt.Sprintf("Error: %v\n", err)
+		return
+	}
+
+	for _, ln := range strings.Split(string(output), "\n") {
+		switch {
+		case strings.Contains(ln, "Apache Maven"):
+			fmt.Printf("%v\n", ln)
+			versionRegex := regexp.MustCompile(`Apache Maven ([1-9]+)(\.([0-9]+)){2,3}`)
+			matches := versionRegex.FindStringSubmatch(ln)
+			if len(matches) < 2 {
+				_ = fmt.Sprintf("Unable to determine Apache Maven version: %s\n", ln)
+				return
+			}
+		case strings.Contains(ln, "Java version"):
+			fmt.Printf("%v\n", ln)
+			versionRegex := regexp.MustCompile(`version: ([1-9]+)(\.([0-9]+)){2,3}`)
+			matches := versionRegex.FindStringSubmatch(ln)
+			if len(matches) < 2 {
+				_ = fmt.Sprintf("Unable to determine Java version: %s\n", ln)
+				return
+			}
+			majorVersion, err := strconv.Atoi(matches[1])
+			if err != nil {
+				_ = fmt.Sprintf("Error parsing Java version: %s - %v\n", ln, err)
+				return
+			}
+			if majorVersion < 17 {
+				_ = fmt.Sprintf("JDK version is below 17: %s\n", ln)
+				return
+			}
+		}
+	}
+}

docs/modules/ROOT/pages/contributing/developers.adoc

@@ -24,6 +24,8 @@ In order to build the project, you need to comply with the following requirement
 
 * **Go version 1.16+**: needed to compile and test the project. Refer to the https://golang.org/[Go website] for the installation.
 * **GNU Make**: used to define composite build actions. This should be already installed or available as a package if you have a good OS (https://www.gnu.org/software/make/).
+* **JDK version 17+**: the build requires JDK version 17 or above. This corresponds to the JDK version of the integration base image.
+* **Maven version 3.8+**: the build requires Maven 3.8 or above. This corresponds to the version defined in the `build/Dockerfile`.
 * **MinGW**: needed to compile the project on Windows. Refer to the https://www.mingw-w64.org/[MinGW website] for the installation.
 * **Windows Subsystem for Linux (WSL)**: for running Linux binary executables natively on Windows. Refer to https://docs.microsoft.com/en-us/windows/wsl/install[WSL Website] for installation. Alternatively, you can use https://www.cygwin.com/[Cygwin] or https://www.educative.io/edpresso/how-to-install-git-bash-in-windows[Git Bash].
 

script/Makefile

@@ -230,7 +230,10 @@ build-platform: build build-kamel-platform
 
 ci-build: clean codegen set-version check-licenses dir-licenses build-kamel cross-compile
 
-do-build: gotestfmt-install
+check_jdk_version:
+	@go run ./cmd/util/check_jdk_version
+
+do-build: gotestfmt-install check_jdk_version
 ifeq ($(DO_TEST_PREBUILD),true)
 TEST_PREBUILD = build
 else