ModelCacheSizeAutoUpdater.java

package org.netbeans.gradle.project;

import java.nio.file.Path;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import org.jtrim.concurrent.GenericUpdateTaskExecutor;
import org.jtrim.concurrent.TaskExecutor;
import org.jtrim.concurrent.UpdateTaskExecutor;
import org.jtrim.utils.ExceptionHelper;
import org.netbeans.api.project.Project;
import org.netbeans.api.project.ui.OpenProjects;
import org.netbeans.gradle.project.model.DefaultGradleModelLoader;
import org.netbeans.gradle.project.model.NbGradleModel;
import org.netbeans.gradle.project.model.NbGradleMultiProjectDef;
import org.netbeans.gradle.project.model.ProjectModelChangeListener;
import org.netbeans.gradle.project.util.NbConsumer;
import org.netbeans.gradle.project.util.NbTaskExecutors;

public final class ModelCacheSizeAutoUpdater implements ProjectModelChangeListener {
    private static final ModelCacheSizeAutoUpdater DEFAULT = new ModelCacheSizeAutoUpdater(NbTaskExecutors.newDefaultUpdateExecutor(), new NbConsumer<Integer>() {
        @Override
        public void accept(Integer requiredCacheSize) {
            DefaultGradleModelLoader.ensureCacheSize(requiredCacheSize);
        }
    });

    private final UpdateTaskExecutor cacheSizeCheckExecutor;
    private final NbConsumer<? super Integer> cacheSizeUpdater;

    public ModelCacheSizeAutoUpdater(TaskExecutor cacheSizeCheckExecutor, NbConsumer<? super Integer> cacheSizeUpdater) {
        this(new GenericUpdateTaskExecutor(cacheSizeCheckExecutor), cacheSizeUpdater);
    }

    public ModelCacheSizeAutoUpdater(UpdateTaskExecutor cacheSizeCheckExecutor, NbConsumer<? super Integer> cacheSizeUpdater) {
        ExceptionHelper.checkNotNullArgument(cacheSizeCheckExecutor, "cacheSizeCheckExecutor");
        ExceptionHelper.checkNotNullArgument(cacheSizeUpdater, "cacheSizeUpdater");

        this.cacheSizeCheckExecutor = cacheSizeCheckExecutor;
        this.cacheSizeUpdater = cacheSizeUpdater;
    }

    public static ModelCacheSizeAutoUpdater getDefault() {
        return DEFAULT;
    }

    @Override
    public void onModelChanged() {
        cacheSizeCheckExecutor.execute(new Runnable() {
            @Override
            public void run() {
                checkCacheSize();
            }
        });
    }

    private void checkCacheSize() {
        Project[] projects = OpenProjects.getDefault().getOpenProjects();
        Map<Path, Integer> projectSizes = getProjectSizes(projects);

        int requiredCacheSize = sum(projectSizes.values());
        cacheSizeUpdater.accept(requiredCacheSize);
    }

    private static int sum(Collection<Integer> values) {
        int result = 0;
        for (Integer value: values) {
            result += value;
        }
        return result;
    }

    private static Map<Path, Integer> getProjectSizes(Project[] projects) {
        Map<Path, Integer> projectSizes = null;
        for (Project project: projects) {
            NbGradleProject gradleProject = project.getLookup().lookup(NbGradleProject.class);
            if (gradleProject != null && gradleProject.wasModelEverSet()) {
                NbGradleModel projectModel = gradleProject.currentModel().getValue();
                NbGradleMultiProjectDef projectDef = projectModel.getGenericInfo().getProjectDef();
                int numberOfProjectsInThisBuild = projectDef.getNumberOfProjectsInThisBuild();

                if (projectSizes == null) {
                    projectSizes = new HashMap<>();
                }
                // +1 for a possible buildSrc
                projectSizes.put(projectModel.getSettingsDir(), numberOfProjectsInThisBuild + 1);
            }
        }

        return projectSizes != null ? projectSizes : Collections.<Path, Integer>emptyMap();
    }
}