onl.area51.httpd.util.ContentTypeResolver.java Source code

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Here is the source code for onl.area51.httpd.util.ContentTypeResolver.java

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/*
 * Copyright 2016 peter.
 *
 * 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 onl.area51.httpd.util;

import java.io.File;
import java.nio.file.Path;
import java.util.Map;
import java.util.Objects;
import java.util.concurrent.ConcurrentHashMap;
import org.apache.http.entity.ContentType;
import static org.apache.http.entity.ContentType.*;

/**
 * Utility class to handle the resolution of {@link ContentType} based on a file name.
 *
 * @author peter
 */
public class ContentTypeResolver {

    public static final ContentType PNG = create("image/png");
    public static final ContentType JPG = create("image/jpg");
    private static final Map<String, ContentType> CONTENT_TYPES;

    static {
        CONTENT_TYPES = new ConcurrentHashMap<>();
        CONTENT_TYPES.put(".htm", TEXT_HTML);
        CONTENT_TYPES.put(".html", TEXT_HTML);
        CONTENT_TYPES.put(".jpg", JPG);
        CONTENT_TYPES.put(".jpeg", JPG);
        CONTENT_TYPES.put(".json", APPLICATION_JSON);
        CONTENT_TYPES.put(".log", TEXT_PLAIN);
        CONTENT_TYPES.put(".png", PNG);
        CONTENT_TYPES.put(".text", TEXT_PLAIN);
        CONTENT_TYPES.put(".txt", TEXT_PLAIN);
        CONTENT_TYPES.put(".xml", TEXT_XML);
    }

    public static void register(String suffix, ContentType ct) {
        Objects.requireNonNull(suffix);
        Objects.requireNonNull(ct);
        String s = suffix.trim().toLowerCase();
        int i = suffix.lastIndexOf('.');
        if (i > 0) {
            throw new IllegalArgumentException("Invalid suffix " + suffix);
        }
        CONTENT_TYPES.putIfAbsent(i == 0 ? s : ("." + s), ct);
    }

    public static ContentType resolve(String path) {
        if (path != null && !path.isEmpty()) {
            int i = path.lastIndexOf('.');
            int j = path.lastIndexOf('/');
            if (i > -1 && i > j) {
                return CONTENT_TYPES.getOrDefault(path.substring(i).toLowerCase(), APPLICATION_OCTET_STREAM);
            }
        }
        return ContentType.APPLICATION_OCTET_STREAM;
    }

    public static ContentType resolve(File f) {
        return resolve(f == null ? null : f.getName());
    }

    public static ContentType resolve(Path p) {
        return resolve(p == null ? null : p.getName(p.getNameCount() - 1).toString());
    }
}