service to detect java version;

highlight access to private class members according to java version used (IDEA-83045)

java/java-psi-api/src/com/intellij/openapi/projectRoots/JavaSdkVersion.java

@@ -0,0 +1,74 @@
+/*
+ * Copyright 2000-2011 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.openapi.projectRoots;
+
+import com.intellij.pom.java.LanguageLevel;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.Arrays;
+
+/**
+ * Represents version of Java SDK. Use {@link JavaSdk#getVersion(Sdk)} method to obtain version of an {@link Sdk}
+ *
+ * @author nik
+ */
+public enum JavaSdkVersion {
+  JDK_1_0(LanguageLevel.JDK_1_3, "1.0"), JDK_1_1(LanguageLevel.JDK_1_3, "1.1"), JDK_1_2(LanguageLevel.JDK_1_3, "1.2"), JDK_1_3(LanguageLevel.JDK_1_3, "1.3"),
+  JDK_1_4(LanguageLevel.JDK_1_4, "1.4"),
+  JDK_1_5(LanguageLevel.JDK_1_5, "1.5"),
+  JDK_1_6(LanguageLevel.JDK_1_6, "1.6"),
+  JDK_1_7(LanguageLevel.JDK_1_7, "1.7"),
+  JDK_1_8(LanguageLevel.JDK_1_8, "1.8");
+  private final LanguageLevel myMaxLanguageLevel;
+  private final String myDescription;
+
+  JavaSdkVersion(@NotNull LanguageLevel maxLanguageLevel, @NotNull String description) {
+    myMaxLanguageLevel = maxLanguageLevel;
+    myDescription = description;
+  }
+
+  @NotNull
+  public LanguageLevel getMaxLanguageLevel() {
+    return myMaxLanguageLevel;
+  }
+
+  @NotNull
+  public String getDescription() {
+    return myDescription;
+  }
+
+  public boolean isAtLeast(@NotNull JavaSdkVersion version) {
+    return compareTo(version) >= 0;
+  }
+
+  @Override
+  public String toString() {
+    return super.toString() + ", description: " + myDescription;
+  }
+
+  @NotNull
+  public static JavaSdkVersion byDescription(@NotNull String description) throws IllegalArgumentException {
+    for (JavaSdkVersion version : values()) {
+      if (version.getDescription().equals(description)) {
+        return version;
+      }
+    }
+    throw new IllegalArgumentException(
+      String.format("Can't map Java SDK by description (%s). Available values: %s", description, Arrays.toString(values()))
+    );
+  }
+
+}

java/java-psi-api/src/com/intellij/openapi/projectRoots/JavaVersionService.java

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+/*
+ * Copyright 2000-2012 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * @author max
+ */
+package com.intellij.openapi.projectRoots;
+
+import com.intellij.openapi.components.ServiceManager;
+import com.intellij.psi.PsiElement;
+import com.intellij.psi.util.PsiUtil;
+
+public class JavaVersionService {
+  public static JavaVersionService getInstance() {
+    return ServiceManager.getService(JavaVersionService.class);
+  }
+
+  public boolean isAtLeast(PsiElement element, JavaSdkVersion version) {
+    return PsiUtil.getLanguageLevel(element).isAtLeast(version.getMaxLanguageLevel());
+  }
+}