Fix #6992 Add SPDX checking for copyright/license (java)

Signed-off-by: Nigel Jones <nigel.l.jones+git@gmail.com>

build.gradle

@@ -16,6 +16,7 @@ plugins {
     id 'dev.jacomet.logging-capabilities' version "0.11.0"
     // This plugin helps resolve jakarta/javax dev.jacomet.logging-capabilities
     id 'org.gradlex.java-ecosystem-capabilities' version "1.1"
+    id 'checkstyle'
 }
 
 
@@ -29,6 +30,7 @@ allprojects {
     version = '4.0-SNAPSHOT'
 
     // Mostly java, so default to this for now
+    apply plugin: 'checkstyle'
     apply plugin: 'java'
     apply plugin: 'jacoco'
     apply plugin: 'org.gradlex.java-ecosystem-capabilities'
@@ -423,6 +425,14 @@ allprojects {
     task printSubDependencies(type: DependencyReportTask) {}
     task findDependency(type: DependencyInsightReportTask) {}
 
+    // Checking of headers etc
+    checkstyle {
+        toolVersion = '10.7.0'
+        // Whilst initially adding, soft warnings only, as there are fixes needed
+        ignoreFailures = true
+        showViolations = true
+    }
+
 } // end of allProjects
 
 // Whilst all modules have their own javadoc, we only build
@@ -524,5 +534,7 @@ dependencyAnalysis {
     }
 }
 
+
+
 // Always run dependency check for every regular build
 build.dependsOn("buildHealth")

config/checkstyle/checkstyle.xml

@@ -0,0 +1,17 @@
+<?xml version="1.0"?>
+<!DOCTYPE module PUBLIC
+        "-//Checkstyle//DTD Checkstyle Configuration 1.3//EN"
+        "https://checkstyle.org/dtds/configuration_1_3.dtd">
+<module name="Checker">
+    <module name="TreeWalker">
+
+
+        <module name="Regexp">
+            <property name="format" value="/\*[ ]{1,}SPDX-License-Identifier: Apache-2\.0"/>
+        </module>
+
+        <module name="Regexp">
+            <property name="format" value="/\*[ ]{1,}Copyright Contributors to the( ODPi)? Egeria project"/>
+        </module>
+    </module>
+</module>

config/checkstyle/java.header

@@ -0,0 +1,2 @@
+ ^/* SPDX-License-Identifier: Apache-2.0 */$
+ ^/* Copyright Contributors to the ODPi Egeria project. */$