SystemModules.java

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
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package jdk.internal.module;

import java.lang.module.ModuleDescriptor;
import java.util.Map;
import java.util.Set;

/**
 * A SystemModules object reconstitutes module descriptors and other modules attributes in an efficient way to avoid parsing module-info.class files at startup.
 * Implementations of this class are generated by the "system modules" jlink plugin.
 *
 * @see SystemModuleFinders
 * @see jdk.tools.jlink.internal.plugins.SystemModulesPlugin
 */
/*
 * 系统模块(集)信息，在链接时生成静态信息，以避免解析"module-info.class"，进而提高相关查找效率
 *
 * 参见：
 * jdk.internal.module.SystemModules$all
 * jdk.internal.module.SystemModules$default
 */
interface SystemModules {
    
    /**
     * Returns false if the module reconstituted by this SystemModules object have no overlapping packages.
     * Returns true if there are overlapping packages or unknown.
     */
    boolean hasSplitPackages();
    
    /**
     * Return false if the modules reconstituted by this SystemModules object do not include any incubator modules.
     * Returns true if there are incubating modules or unknown.
     */
    boolean hasIncubatorModules();
    
    /**
     * Returns the non-empty array of ModuleDescriptor objects.
     */
    // 返回当前系统模块内所有模块描述符
    ModuleDescriptor[] moduleDescriptors();
    
    /**
     * Returns the array of ModuleTarget objects.
     * The array elements correspond to the array of ModuleDescriptor objects.
     */
    ModuleTarget[] moduleTargets();
    
    /**
     * Returns the array of ModuleHashes objects.
     * The array elements correspond to the array of ModuleDescriptor objects.
     */
    ModuleHashes[] moduleHashes();
    
    /**
     * Returns the array of ModuleResolution objects.
     * The array elements correspond to the array of ModuleDescriptor objects.
     */
    ModuleResolution[] moduleResolutions();
    
    /**
     * Returns the map representing readability graph for the modules reconstituted by this SystemModules object.
     */
    // 返回系统模块依赖(requires)映射
    Map<String, Set<String>> moduleReads();
    
    /**
     * Returns the map of module exported packages to open.
     * The map key is the module name, the value is the set of exported packages to open.
     */
    // 返回系统模块导出(exports)映射
    Map<String, Set<String>> exportedPackagesToOpen();
    
    /**
     * Returns the map of module concealed packages to open.
     * The map key is the module name, the value is the set of concealed packages to open.
     */
    // 返回系统模块开放(opens)映射
    Map<String, Set<String>> concealedPackagesToOpen();
    
}