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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

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 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

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 *

 * 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,

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 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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package com.sun.tools.jdeps;

import com.sun.tools.classfile.Dependencies;

import com.sun.tools.classfile.Dependency;

import com.sun.tools.classfile.Dependency.Location;

import java.util.HashSet;

import java.util.Set;

import java.util.regex.Pattern;

/*

 * Filter configured based on the input jdeps option

 * 1. -p and -regex to match target dependencies

 * 2. -filter:package to filter out same-package dependencies

 *    This filter is applied when jdeps parses the class files

 *    and filtered dependencies are not stored in the Analyzer.

 * 3. --require specifies to match target dependence from the given module

 *    This gets expanded into package lists to be filtered.

 * 4. -filter:archive to filter out same-archive dependencies

 *    This filter is applied later in the Analyzer as the

 *    containing archive of a target class may not be known until

 *    the entire archive

 */

public class JdepsFilter implements Dependency.Filter, Analyzer.Filter {

    public static final JdepsFilter DEFAULT_FILTER =

        new JdepsFilter.Builder().filter(true, true).build();

    private final Dependency.Filter filter;

    private final Pattern filterPattern;

    private final boolean filterSamePackage;

    private final boolean filterSameArchive;

    private final boolean findJDKInternals;

    private final Pattern includePattern;

    private final Set<String> requires;

    private JdepsFilter(Dependency.Filter filter,

                        Pattern filterPattern,

                        boolean filterSamePackage,

                        boolean filterSameArchive,

                        boolean findJDKInternals,

                        Pattern includePattern,

                        Set<String> requires) {

        this.filter = filter;

        this.filterPattern = filterPattern;

        this.filterSamePackage = filterSamePackage;

        this.filterSameArchive = filterSameArchive;

        this.findJDKInternals = findJDKInternals;

        this.includePattern = includePattern;

        this.requires = requires;

    }

    /**

     * Tests if the given class matches the pattern given in the -include option

     *

     * @param cn fully-qualified name

     */

    public boolean matches(String cn) {

        if (includePattern == null)

            return true;

        if (includePattern != null)

            return includePattern.matcher(cn).matches();

        return false;

    }

    /**

     * Tests if the given source includes classes specified in -include option

     *

     * This method can be used to determine if the given source should eagerly

     * be processed.

     */

    public boolean matches(Archive source) {

        if (includePattern != null) {

            return source.reader().entries().stream()

                    .map(name -> name.replace('/', '.'))

                    .filter(name -> !name.equals("module-info.class"))

                    .anyMatch(this::matches);

        }

        return hasTargetFilter();

    }

    public boolean hasIncludePattern() {

    }

    public boolean hasTargetFilter() {

        return filter != null;

    }

    public Set<String> requiresFilter() {

        return requires;

    }

    // ----- Dependency.Filter -----

    @Override

    public boolean accepts(Dependency d) {

        if (d.getOrigin().equals(d.getTarget()))

            return false;

        // filter same package dependency

        String pn = d.getTarget().getPackageName();

        if (filterSamePackage && d.getOrigin().getPackageName().equals(pn)) {

            return false;

        }

        // filter if the target package matches the given filter

        if (filterPattern != null && filterPattern.matcher(pn).matches()) {

            return false;

        }

        // filter if the target matches the given filtered package name or regex

        return filter != null ? filter.accepts(d) : true;

    }

    // ----- Analyzer.Filter ------

    /**

     * Filter depending on the containing archive or module

     */

    @Override

    public boolean accepts(Location origin, Archive originArchive,

                           Location target, Archive targetArchive) {

        if (findJDKInternals) {

            // accepts target that is JDK class but not exported

            Module module = targetArchive.getModule();

            return originArchive != targetArchive &&

                    isJDKInternalPackage(module, target.getPackageName());

        } else if (filterSameArchive) {

            // accepts origin and target that from different archive

            return originArchive != targetArchive;

        }

        return true;

    }

    /**

     * Tests if the package is an internal package of the given module.

     */

    public boolean isJDKInternalPackage(Module module, String pn) {

        if (module.isJDKUnsupported()) {

            // its exported APIs are unsupported

            return true;

        }

        return module.isJDK() && !module.isExported(pn);

    }

    @Override

    public String toString() {

        StringBuilder sb = new StringBuilder();

        sb.append("include pattern: ").append(includePattern).append("\n");

        sb.append("filter same archive: ").append(filterSameArchive).append("\n");

        sb.append("filter same package: ").append(filterSamePackage).append("\n");

        sb.append("requires: ").append(requires).append("\n");

        return sb.toString();

    }

    public static class Builder {

        Pattern filterPattern;

        Pattern regex;

        boolean filterSamePackage;

        boolean filterSameArchive;

        boolean findJDKInterals;

        // source filters

        Pattern includePattern;

        Set<String> requires = new HashSet<>();

        Set<String> targetPackages = new HashSet<>();

        public Builder packages(Set<String> packageNames) {

            this.targetPackages.addAll(packageNames);

            return this;

        }

        public Builder regex(Pattern regex) {

            this.regex = regex;

            return this;

        }

        public Builder filter(Pattern regex) {

            this.filterPattern = regex;

            return this;

        }

        public Builder filter(boolean samePackage, boolean sameArchive) {

            this.filterSamePackage = samePackage;

            this.filterSameArchive = sameArchive;

            return this;

        }

        public Builder requires(String name, Set<String> packageNames) {

            this.requires.add(name);

            this.targetPackages.addAll(packageNames);

            return this;

        }

        public Builder findJDKInternals(boolean value) {

            this.findJDKInterals = value;

            return this;

        }

        public Builder includePattern(Pattern regex) {

            this.includePattern = regex;

            return this;

        }

        public JdepsFilter build() {

            Dependency.Filter filter = null;

            if (regex != null)

                filter = Dependencies.getRegexFilter(regex);

            else if (!targetPackages.isEmpty()) {

                filter = Dependencies.getPackageFilter(targetPackages, false);

            }

            return new JdepsFilter(filter,

                                   filterPattern,

                                   filterSamePackage,

                                   filterSameArchive,

                                   findJDKInterals,

                                   includePattern,

                                   requires);

        }

    }

}