[JENKINS-55048] Add support for plugin Java requirement metadata

core/src/main/java/hudson/PluginManager.java

@@ -1824,6 +1824,9 @@ public List<Future<UpdateCenter.UpdateCenterJob>> prevalidateConfig(InputStream
                 if (toInstall.isForNewerHudson()) {
                     LOGGER.log(WARNING, "{0}@{1} was built for a newer Jenkins", new Object[] {toInstall.name, toInstall.version});
                 }
+                if (toInstall.isForNewerJava()) {
+                    LOGGER.log(WARNING, "{0}@{1} was built for a newer Java", new Object[] {toInstall.name, toInstall.version});
+                }
                 jobs.add(toInstall.deploy(true));
             } else if (pw.isOlderThan(requestedPlugin.getValue())) { // upgrade
                 UpdateSite.Plugin toInstall = uc.getPlugin(requestedPlugin.getKey(), requestedPlugin.getValue());
@@ -1841,6 +1844,9 @@ public List<Future<UpdateCenter.UpdateCenterJob>> prevalidateConfig(InputStream
                 if (toInstall.isForNewerHudson()) {
                     LOGGER.log(WARNING, "{0}@{1} was built for a newer Jenkins", new Object[] {toInstall.name, toInstall.version});
                 }
+                if (toInstall.isForNewerJava()) {
+                    LOGGER.log(WARNING, "{0}@{1} was built for a newer Java", new Object[] {toInstall.name, toInstall.version});
+                }
                 if (!toInstall.isCompatibleWithInstalledVersion()) {
                     LOGGER.log(WARNING, "{0}@{1} is incompatible with the installed @{2}", new Object[] {toInstall.name, toInstall.version, pw.getVersion()});
                 }

core/src/main/java/hudson/PluginWrapper.java

@@ -35,6 +35,7 @@
 import hudson.util.VersionNumber;
 import jenkins.YesNoMaybe;
 import jenkins.model.Jenkins;
+import jenkins.util.java.JavaUtils;
 import org.apache.commons.lang.StringUtils;
 import org.apache.commons.logging.LogFactory;
 import org.kohsuke.accmod.Restricted;
@@ -495,6 +496,20 @@ private String getVersionOf(Manifest manifest) {
         return null;
     }
 
+    /**
+     * Returns the minimum Java version of this plugin, as specified in the plugin metadata.
+     * Generally coming from the <code>java.level</code> extracted as MANIFEST's metadata with
+     * <a href="https://github.com/jenkinsci/plugin-pom/pull/134">this addition on the plugins' parent pom</a>.
+     *
+     * @see <a href="https://github.com/jenkinsci/maven-hpi-plugin/pull/75">maven-hpi-plugin#PR-75</a>.
+     *
+     * @since TODO
+     */
+    @Exported
+    public @CheckForNull String getMinimumJavaVersion() {
+        return manifest.getMainAttributes().getValue("Minimum-Java-Version");
+    }
+
     /**
      * Returns the version number of this plugin
      */
@@ -745,6 +760,14 @@ public boolean hasLicensesXml() {
                     versionDependencyError(Messages.PluginWrapper_obsoleteCore(Jenkins.getVersion().toString(), requiredCoreVersion), Jenkins.getVersion().toString(), requiredCoreVersion);
                 }
             }
+
+            String minimumJavaVersion = getMinimumJavaVersion();
+            if (minimumJavaVersion != null) {
+                VersionNumber actualVersion = JavaUtils.getCurrentJavaRuntimeVersionNumber();
+                if (actualVersion.isOlderThan(new VersionNumber(minimumJavaVersion))) {
+                    versionDependencyError(Messages.PluginWrapper_obsoleteJava(actualVersion.toString(), minimumJavaVersion), actualVersion.toString(), minimumJavaVersion);
+                }
+            }
         }
         // make sure dependencies exist
         for (Dependency d : dependencies) {

core/src/main/java/hudson/model/UpdateSite.java

@@ -70,6 +70,7 @@
 import jenkins.security.UpdateSiteWarningsConfiguration;
 import jenkins.util.JSONSignatureValidator;
 import jenkins.util.SystemProperties;
+import jenkins.util.java.JavaUtils;
 import net.sf.json.JSONArray;
 import net.sf.json.JSONException;
 import net.sf.json.JSONObject;
@@ -967,6 +968,13 @@ public final class Plugin extends Entry {
          */
         @Exported
         public final String requiredCore;
+        /**
+         * Version of Java this plugin requires to run.
+         *
+         * @since TODO
+         */
+        @Exported
+        public final String minimumJavaVersion;
         /**
          * Categories for grouping plugins, taken from labels assigned to wiki page.
          * Can be null.
@@ -993,6 +1001,7 @@ public Plugin(String sourceId, JSONObject o) {
             this.title = get(o,"title");
             this.excerpt = get(o,"excerpt");
             this.compatibleSinceVersion = Util.intern(get(o,"compatibleSinceVersion"));
+            this.minimumJavaVersion = Util.intern(get(o, "minimumJavaVersion"));
             this.requiredCore = Util.intern(get(o,"requiredCore"));
             this.categories = o.has("labels") ? internInPlace((String[])o.getJSONArray("labels").toArray(EMPTY_STRING_ARRAY)) : null;
             JSONArray ja = o.getJSONArray("dependencies");
@@ -1118,6 +1127,21 @@ public boolean isForNewerHudson() {
             }
         }
 
+        /**
+         * Returns true iff the plugin declares a minimum Java version and it's newer than what the Jenkins master is running on.
+         * @since TODO
+         */
+        public boolean isForNewerJava() {
+            try {
+                final VersionNumber currentRuntimeJavaVersion = JavaUtils.getCurrentJavaRuntimeVersionNumber();
+                return minimumJavaVersion != null && new VersionNumber(minimumJavaVersion).isNewerThan(
+                        currentRuntimeJavaVersion);
+            } catch (NumberFormatException nfe) {
+                logBadMinJavaVersion();
+                return false; // treat this as undeclared minimum Java version
+            }
+        }
+
         public VersionNumber getNeededDependenciesRequiredCore() {
             VersionNumber versionNumber = null;
             try {
@@ -1132,6 +1156,36 @@ public VersionNumber getNeededDependenciesRequiredCore() {
             return versionNumber;
         }
 
+        /**
+         * Returns the minimum Java version needed to use the plugin and all its dependencies.
+         * @since TODO
+         * @return the minimum Java version needed to use the plugin and all its dependencies, or null if unspecified.
+         */
+        @CheckForNull
+        public VersionNumber getNeededDependenciesMinimumJavaVersion() {
+            VersionNumber versionNumber = null;
+            try {
+                versionNumber = minimumJavaVersion == null ? null : new VersionNumber(minimumJavaVersion);
+            } catch (NumberFormatException nfe) {
+                logBadMinJavaVersion();
+            }
+            for (Plugin p: getNeededDependencies()) {
+                VersionNumber v = p.getNeededDependenciesMinimumJavaVersion();
+                if (v == null) {
+                    continue;
+                }
+                if (versionNumber == null || v.isNewerThan(versionNumber)) {
+                    versionNumber = v;
+                }
+            }
+            return versionNumber;
+        }
+
+        private void logBadMinJavaVersion() {
+            LOGGER.log(Level.WARNING, "minimumJavaVersion was specified for plugin {0} but unparseable (received {1})",
+                       new String[]{this.name, this.minimumJavaVersion});
+        }
+
         public boolean isNeededDependenciesForNewerJenkins() {
             return isNeededDependenciesForNewerJenkins(new PluginManager.MetadataCache());
         }
@@ -1148,6 +1202,20 @@ public boolean isNeededDependenciesForNewerJenkins(PluginManager.MetadataCache c
             });
         }
 
+        /**
+         * Returns true iff any of the plugin dependencies require a newer Java than Jenkins is running on.
+         *
+         * @since TODO
+         */
+        public boolean isNeededDependenciesForNewerJava() {
+            for (Plugin p: getNeededDependencies()) {
+                if (p.isForNewerJava() || p.isNeededDependenciesForNewerJava()) {
+                    return true;
+                }
+            }
+            return false;
+        }
+
         /**
          * If at least some of the plugin's needed dependencies are already installed, and the new version of the
          * needed dependencies plugin have a "compatibleSinceVersion"

core/src/main/java/jenkins/install/SetupWizard.java

@@ -500,7 +500,7 @@ public JSONArray getPlatformPluginUpdates() {
                                         for (UpdateSite site : jenkins.getUpdateCenter().getSiteList()) {
                                             UpdateSite.Plugin sitePlug = site.getPlugin(pluginName);
                                             if (sitePlug != null
-                                                    && !sitePlug.isForNewerHudson()
+                                                    && !sitePlug.isForNewerHudson() && !sitePlug.isForNewerJava()
                                                     && !sitePlug.isNeededDependenciesForNewerJenkins()) {
                                                 foundCompatibleVersion = true;
                                                 break;

core/src/main/java/jenkins/util/java/JavaUtils.java

@@ -23,6 +23,7 @@
  */
 package jenkins.util.java;
 
+import hudson.util.VersionNumber;
 import org.kohsuke.accmod.Restricted;
 import org.kohsuke.accmod.restrictions.NoExternalUse;
 
@@ -42,7 +43,7 @@ private JavaUtils() {
      * @return {@code true} if it is Java 8 or older version
      */
     public static boolean isRunningWithJava8OrBelow() {
-        String javaVersion = System.getProperty("java.specification.version");
+        String javaVersion = getCurrentRuntimeJavaVersion();
         return javaVersion.startsWith("1.");
     }
 
@@ -51,8 +52,23 @@ public static boolean isRunningWithJava8OrBelow() {
      * @return {@code true} if it is Java 9 or above
      */
     public static boolean isRunningWithPostJava8() {
-        String javaVersion = System.getProperty("java.specification.version");
+        String javaVersion = getCurrentRuntimeJavaVersion();
         return !javaVersion.startsWith("1.");
     }
 
+    /**
+     * Returns the JVM's current version as a {@link VersionNumber} instance.
+     */
+    public static VersionNumber getCurrentJavaRuntimeVersionNumber() {
+        return new VersionNumber(getCurrentRuntimeJavaVersion());
+    }
+
+    /**
+     * Returns the JVM's current version as a {@link String}.
+     * @see System#getProperty(String)
+     */
+    public static String getCurrentRuntimeJavaVersion() {
+        // TODO: leverage Runtime.version() once on Java 9+
+        return System.getProperty("java.specification.version");
+    }
 }

core/src/main/resources/hudson/Messages.properties

@@ -79,13 +79,14 @@ ProxyConfiguration.Success=Success
 
 Functions.NoExceptionDetails=No Exception details
 
-PluginWrapper.missing={0} v{1} is missing. To fix, install v{1} or later.
-PluginWrapper.failed_to_load_plugin={0} v{1} failed to load.
-PluginWrapper.failed_to_load_dependency={0} v{1} failed to load. Fix this plugin first.
-PluginWrapper.disabledAndObsolete={0} v{1} is disabled and older than required. To fix, install v{2} or later and enable it.
+PluginWrapper.missing={0} version {1} is missing. To fix, install version {1} or later.
+PluginWrapper.failed_to_load_plugin={0} version {1} failed to load.
+PluginWrapper.failed_to_load_dependency={0} version {1} failed to load. Fix this plugin first.
+PluginWrapper.disabledAndObsolete={0} version {1} is disabled and older than required. To fix, install version {2} or later and enable it.
 PluginWrapper.disabled={0} is disabled. To fix, enable it.
-PluginWrapper.obsolete={0} v{1} is older than required. To fix, install v{2} or later.
-PluginWrapper.obsoleteCore=You must update Jenkins from v{0} to v{1} or later to run this plugin.
+PluginWrapper.obsolete={0} version {1} is older than required. To fix, install version {2} or later.
+PluginWrapper.obsoleteCore=You must update Jenkins from version {0} to version {1} or later to run this plugin.
+PluginWrapper.obsoleteJava=You must update Java from version {0} to version {1} or later to run this plugin.
 PluginWrapper.PluginWrapperAdministrativeMonitor.DisplayName=Plugins Failed To Load
 PluginWrapper.Already.Disabled=The plugin ''{0}'' was already disabled
 PluginWrapper.Plugin.Has.Dependant=The plugin ''{0}'' has, at least, one dependant plugin ({1}) and the disable strategy is {2}, so it cannot be disabled

core/src/main/resources/hudson/PluginManager/_table.css

@@ -8,3 +8,6 @@
     margin: 1em;
     text-align: right;
 }
+.compatWarning, .securityWarning {
+    font-weight: bold;
+}

core/src/main/resources/hudson/PluginManager/table.jelly

@@ -107,12 +107,18 @@ THE SOFTWARE.
                       <j:if test="${p.isForNewerHudson()}">
                         <div class="compatWarning">${%coreWarning(p.requiredCore)}</div>
                       </j:if>
+                      <j:if test="${p.isForNewerJava()}">
+                        <div class="compatWarning">${%javaWarning(p.minimumJavaVersion)}</div>
+                      </j:if>
                       <j:if test="${!p.isNeededDependenciesCompatibleWithInstalledVersion(cache)}">
                         <div class="compatWarning">${%depCompatWarning}</div>
                       </j:if>
                       <j:if test="${p.isNeededDependenciesForNewerJenkins(cache)}">
                         <div class="compatWarning">${%depCoreWarning(p.getNeededDependenciesRequiredCore().toString())}</div>
                       </j:if>
+                      <j:if test="${p.isNeededDependenciesForNewerJava()}">
+                        <div class="compatWarning">${%depJavaWarning(p.getNeededDependenciesMinimumJavaVersion().toString())}</div>
+                      </j:if>
                       <j:if test="${p.hasWarnings()}">
                         <div class="securityWarning">${%securityWarning}
                           <ul>

core/src/main/resources/hudson/PluginManager/table.properties

@@ -26,6 +26,9 @@ compatWarning=\
 coreWarning=\
  Warning: This plugin is built for Jenkins {0} or newer. \
  Jenkins will refuse to load this plugin if installed.
+javaWarning=\
+ Warning: This plugin requires Java {0} or newer. \
+ Jenkins will refuse to load this plugin if installed.
 depCompatWarning=\
  Warning: This plugin requires dependent plugins be upgraded and at least one of these dependent plugins claims to use a different settings format than the installed version. \
  Jobs using that plugin may need to be reconfigured, and/or you may not be able to cleanly revert to the prior version without manually restoring old settings. \
@@ -34,6 +37,10 @@ depCoreWarning=\
  Warning: This plugin requires dependent plugins that require Jenkins {0} or newer. \
  Jenkins will refuse to load the dependent plugins requiring a newer version of Jenkins, \
  and in turn loading this plugin will fail.
+depJavaWarning=\
+ Warning: this plugin requires other plugins which in turn require Java {0} or newer. \
+ Jenkins will refuse to load the dependent plugins requiring a newer version of Jenkins, \
+ and in turn loading this plugin will fail.
 securityWarning=\
   Warning: This plugin version may not be safe to use. Please review the following security notices:
 

core/src/test/java/hudson/PluginWrapperTest.java

@@ -53,7 +53,7 @@ public void jenkinsCoreTooOld() throws Exception {
             pw.resolvePluginDependencies();
             fail();
         } catch (IOException ex) {
-            assertContains(ex, "fake v42 failed to load", "update Jenkins from v2.0 to v3.0");
+            assertContains(ex, "fake version 42 failed to load", "update Jenkins from version 2.0 to version 3.0");
         }
     }
 
@@ -64,7 +64,7 @@ public void dependencyNotInstalled() throws Exception {
             pw.resolvePluginDependencies();
             fail();
         } catch (IOException ex) {
-            assertContains(ex, "dependee v42 failed to load", "dependency v42 is missing. To fix, install v42 or later");
+            assertContains(ex, "dependee version 42 failed to load", "dependency version 42 is missing. To fix, install version 42 or later");
         }
     }
 
@@ -76,7 +76,7 @@ public void dependencyOutdated() throws Exception {
             pw.resolvePluginDependencies();
             fail();
         } catch (IOException ex) {
-            assertContains(ex, "dependee v42 failed to load", "dependency v3 is older than required. To fix, install v5 or later");
+            assertContains(ex, "dependee version 42 failed to load", "dependency version 3 is older than required. To fix, install version 5 or later");
         }
     }
 
@@ -88,7 +88,7 @@ public void dependencyFailedToLoad() throws Exception {
             pw.resolvePluginDependencies();
             fail();
         } catch (IOException ex) {
-            assertContains(ex, "dependee v42 failed to load", "dependency v5 failed to load. Fix this plugin first");
+            assertContains(ex, "dependee version 42 failed to load", "dependency version 5 failed to load. Fix this plugin first");
         }
     }
 

test/src/test/java/hudson/model/UpdateSiteTest.java

@@ -153,6 +153,32 @@ public void shutdownWebserver() throws Exception {
         assertNotEquals("plugin data is present", Collections.emptyMap(), site.getData().plugins);
     }
 
+    @Issue("JENKINS-55048")
+    @Test public void minimumJavaVersion() throws Exception {
+        // TODO: factor out the sites init
+        PersistedList<UpdateSite> sites = j.jenkins.getUpdateCenter().getSites();
+        sites.clear();
+        URL url = new URL(baseUrl, "/plugins/minJavaVersion-update-center.json");
+        UpdateSite site = new UpdateSite(UpdateCenter.ID_DEFAULT, url.toString());
+        sites.add(site);
+        assertEquals(FormValidation.ok(), site.updateDirectly(false).get());
+        // END TODO
+
+        final UpdateSite.Plugin tasksPlugin = site.getPlugin("tasks");
+        assertNotNull(tasksPlugin);
+        assertFalse(tasksPlugin.isNeededDependenciesForNewerJava());
+        assertFalse(tasksPlugin.isForNewerJava());
+
+        final UpdateSite.Plugin pluginCompiledForTooRecentJava = site.getPlugin("java-too-recent");
+        assertFalse(pluginCompiledForTooRecentJava.isNeededDependenciesForNewerJava());
+        assertTrue(pluginCompiledForTooRecentJava.isForNewerJava());
+
+        final UpdateSite.Plugin pluginDependingOnPluginCompiledForTooRecentJava = site.getPlugin("depending-on-too-recent-java");
+        assertTrue(pluginDependingOnPluginCompiledForTooRecentJava.isNeededDependenciesForNewerJava());
+        assertFalse(pluginDependingOnPluginCompiledForTooRecentJava.isForNewerJava());
+
+    }
+
     @Issue("JENKINS-31448")
     @Test public void isLegacyDefault() throws Exception {
         assertFalse("isLegacyDefault should be false with null id",new UpdateSite(null,"url").isLegacyDefault());