net.adamjak.thomas.graph.library.utils.ClassFinder.java Source code

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Here is the source code for net.adamjak.thomas.graph.library.utils.ClassFinder.java

Source

package net.adamjak.thomas.graph.library.utils;

import com.google.common.reflect.ClassPath;

import java.io.IOException;
import java.lang.annotation.Annotation;
import java.util.LinkedHashSet;
import java.util.Set;

/**
 * Created by Tomas Adamjak on 17.7.2016.
 * Copyright 2016, Tomas Adamjak
 * License: The BSD 3-Clause License
 */
public class ClassFinder {
    private final ClassLoader classLoader;

    public ClassFinder() {
        this.classLoader = getClass().getClassLoader();
    }

    /**
     * @param classes {@link Set} of classes for search
     * @param extendedClass Class whitch found class must extends
     * @return Return only classes whitch extends class from param {@code extendedClass}.
     */
    public Set<Class<?>> findClassesWhitchExtends(Set<Class<?>> classes, Class<?> extendedClass) {
        if (classes == null || extendedClass == null)
            throw new IllegalArgumentException("Params can not be null.");

        Set<Class<?>> classesWhitchExtends = new LinkedHashSet<Class<?>>();

        for (Class<?> c : classes) {
            if (c.getSuperclass().equals(extendedClass)) {
                classesWhitchExtends.add(c);
            }
        }

        return classesWhitchExtends;
    }

    /**
     * Find all annoted classes from package and subpackages.
     *
     * @param packageNames {@link Set} of package name with annoted classes
     * @param annotation find annotation
     * @return {@link Set}&lt;{@link Class}&lt;?&gt;&gt; of annoted classes.
     */
    public Set<Class<?>> findAnnotatedClasses(Set<String> packageNames, Class<? extends Annotation>... annotation) {
        Set<Class<?>> classes = this.findClasses(packageNames);
        Set<Class<?>> annotatedClasses = new LinkedHashSet<Class<?>>();

        if (classes == null || classes.isEmpty() || (annotation == null || annotation.length == 0)) {
            return annotatedClasses;
        }

        for (Class<?> c : classes) {
            for (Annotation a : c.getAnnotations()) {
                for (Class<? extends Annotation> ac : annotation) {
                    if (ac.equals(a.annotationType())) {
                        annotatedClasses.add(c);
                        break;
                    }
                }
            }
        }

        return annotatedClasses;
    }

    /**
     * Find all classes in package and subpackages.
     *
     * @param packageNames {@link Set} of package name with annoted classes
     * @return {@link Set}&lt;{@link Class}&lt;?&gt;&gt; found classes.
     */
    public Set<Class<?>> findClasses(Set<String> packageNames) {
        Set<Class<?>> classes = new LinkedHashSet<Class<?>>();

        try {
            for (String packageName : packageNames) {
                Set<ClassPath.ClassInfo> classesInPackage = ClassPath.from(this.classLoader)
                        .getTopLevelClassesRecursive(packageName);
                for (ClassPath.ClassInfo ci : classesInPackage) {
                    classes.add(ci.load());
                }
            }
        } catch (IOException e) {
            e.printStackTrace();
        }

        return classes;
    }
}