platform/lang-impl/src/com/intellij/openapi/projectRoots/ex/PathUtilEx.java

/*
 * 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.
 */

package com.intellij.openapi.projectRoots.ex;

import com.intellij.openapi.module.Module;
import com.intellij.openapi.module.ModuleManager;
import com.intellij.openapi.project.Project;
import com.intellij.openapi.projectRoots.Sdk;
import com.intellij.openapi.roots.ModuleRootManager;
import com.intellij.openapi.roots.ProjectRootManager;
import com.intellij.openapi.util.text.StringUtil;
import com.intellij.util.Function;
import com.intellij.util.containers.ComparatorUtil;
import com.intellij.util.containers.Convertor;
import org.jetbrains.annotations.Nullable;

import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.List;

import static com.intellij.util.containers.ContainerUtil.map;
import static com.intellij.util.containers.ContainerUtil.skipNulls;

/**
 * @author Eugene Zhuravlev
 *         Date: Apr 14, 2004
 */
public class PathUtilEx {

  private static final Function<Module, Sdk> MODULE_JDK = new Function<Module, Sdk>() {
    @Override
    public Sdk fun(Module module) {
      return ModuleRootManager.getInstance(module).getSdk();
    }
  };
  private static final Convertor<Sdk, String> JDK_VERSION = new Convertor<Sdk, String>() {
    @Override
    public String convert(Sdk jdk) {
      return StringUtil.notNullize(jdk.getVersionString());
    }
  };

  @Nullable
  public static Sdk getAnyJdk(Project project) {
    return chooseJdk(project, Arrays.asList(ModuleManager.getInstance(project).getModules()));
  }

  @Nullable
  public static Sdk chooseJdk(Project project, Collection<Module> modules) {
    Sdk projectJdk = ProjectRootManager.getInstance(project).getProjectSdk();
    if (projectJdk != null) {
      return projectJdk;
    }
    return chooseJdk(modules);
  }

  @Nullable
  public static Sdk chooseJdk(Collection<Module> modules) {
    List<Sdk> jdks = skipNulls(map(skipNulls(modules), MODULE_JDK));
    if (jdks.isEmpty()) {
      return null;
    }
    Collections.sort(jdks, ComparatorUtil.compareBy(JDK_VERSION, String.CASE_INSENSITIVE_ORDER));
    return jdks.get(jdks.size() - 1);
  }
}