Java example source code file (Http2Settings.java)

This example Java source code file (Http2Settings.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

false, http2settings, illegalargumentexception, integer, long, max_concurrent_streams, max_frame_size, max_header_list_size, override, setting, settings_enable_push, settings_header_table_size, settings_initial_window_size, settings_max_frame_size

The Http2Settings.java Java example source code

/*
 * Copyright 2014 The Netty Project
 *
 * The Netty Project licenses this file to you 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 io.netty.handler.codec.http2;

import static io.netty.handler.codec.http2.Http2CodecUtil.MAX_CONCURRENT_STREAMS;
import static io.netty.handler.codec.http2.Http2CodecUtil.MAX_HEADER_LIST_SIZE;
import static io.netty.handler.codec.http2.Http2CodecUtil.MAX_HEADER_TABLE_SIZE;
import static io.netty.handler.codec.http2.Http2CodecUtil.MAX_INITIAL_WINDOW_SIZE;
import static io.netty.handler.codec.http2.Http2CodecUtil.MIN_CONCURRENT_STREAMS;
import static io.netty.handler.codec.http2.Http2CodecUtil.MIN_HEADER_LIST_SIZE;
import static io.netty.handler.codec.http2.Http2CodecUtil.MIN_HEADER_TABLE_SIZE;
import static io.netty.handler.codec.http2.Http2CodecUtil.MIN_INITIAL_WINDOW_SIZE;
import static io.netty.handler.codec.http2.Http2CodecUtil.NUM_STANDARD_SETTINGS;
import static io.netty.handler.codec.http2.Http2CodecUtil.SETTINGS_ENABLE_PUSH;
import static io.netty.handler.codec.http2.Http2CodecUtil.SETTINGS_HEADER_TABLE_SIZE;
import static io.netty.handler.codec.http2.Http2CodecUtil.SETTINGS_INITIAL_WINDOW_SIZE;
import static io.netty.handler.codec.http2.Http2CodecUtil.SETTINGS_MAX_CONCURRENT_STREAMS;
import static io.netty.handler.codec.http2.Http2CodecUtil.SETTINGS_MAX_FRAME_SIZE;
import static io.netty.handler.codec.http2.Http2CodecUtil.SETTINGS_MAX_HEADER_LIST_SIZE;
import static io.netty.handler.codec.http2.Http2CodecUtil.isMaxFrameSizeValid;
import static io.netty.util.internal.ObjectUtil.checkNotNull;

import io.netty.util.collection.CharObjectHashMap;
import io.netty.util.internal.UnstableApi;

/**
 * Settings for one endpoint in an HTTP/2 connection. Each of the values are optional as defined in
 * the spec for the SETTINGS frame. Permits storage of arbitrary key/value pairs but provides helper
 * methods for standard settings.
 */
@UnstableApi
public final class Http2Settings extends CharObjectHashMap<Long> {
    /**
     * Default capacity based on the number of standard settings from the HTTP/2 spec, adjusted so that adding all of
     * the standard settings will not cause the map capacity to change.
     */
    private static final int DEFAULT_CAPACITY = (int) (NUM_STANDARD_SETTINGS / DEFAULT_LOAD_FACTOR) + 1;
    private static final Long FALSE = 0L;
    private static final Long TRUE = 1L;

    public Http2Settings() {
        this(DEFAULT_CAPACITY);
    }

    public Http2Settings(int initialCapacity, float loadFactor) {
        super(initialCapacity, loadFactor);
    }

    public Http2Settings(int initialCapacity) {
        super(initialCapacity);
    }

    /**
     * Adds the given setting key/value pair. For standard settings defined by the HTTP/2 spec, performs
     * validation on the values.
     *
     * @throws IllegalArgumentException if verification for a standard HTTP/2 setting fails.
     */
    @Override
    public Long put(char key, Long value) {
        verifyStandardSetting(key, value);
        return super.put(key, value);
    }

    /**
     * Gets the {@code SETTINGS_HEADER_TABLE_SIZE} value. If unavailable, returns {@code null}.
     */
    public Long headerTableSize() {
        return get(SETTINGS_HEADER_TABLE_SIZE);
    }

    /**
     * Sets the {@code SETTINGS_HEADER_TABLE_SIZE} value.
     *
     * @throws IllegalArgumentException if verification of the setting fails.
     */
    public Http2Settings headerTableSize(int value) {
        put(SETTINGS_HEADER_TABLE_SIZE, Long.valueOf(value));
        return this;
    }

    /**
     * Gets the {@code SETTINGS_ENABLE_PUSH} value. If unavailable, returns {@code null}.
     */
    public Boolean pushEnabled() {
        Long value = get(SETTINGS_ENABLE_PUSH);
        if (value == null) {
            return null;
        }
        return TRUE.equals(value);
    }

    /**
     * Sets the {@code SETTINGS_ENABLE_PUSH} value.
     */
    public Http2Settings pushEnabled(boolean enabled) {
        put(SETTINGS_ENABLE_PUSH, enabled ? TRUE : FALSE);
        return this;
    }

    /**
     * Gets the {@code SETTINGS_MAX_CONCURRENT_STREAMS} value. If unavailable, returns {@code null}.
     */
    public Long maxConcurrentStreams() {
        return get(SETTINGS_MAX_CONCURRENT_STREAMS);
    }

    /**
     * Sets the {@code SETTINGS_MAX_CONCURRENT_STREAMS} value.
     *
     * @throws IllegalArgumentException if verification of the setting fails.
     */
    public Http2Settings maxConcurrentStreams(long value) {
        put(SETTINGS_MAX_CONCURRENT_STREAMS, Long.valueOf(value));
        return this;
    }

    /**
     * Gets the {@code SETTINGS_INITIAL_WINDOW_SIZE} value. If unavailable, returns {@code null}.
     */
    public Integer initialWindowSize() {
        return getIntValue(SETTINGS_INITIAL_WINDOW_SIZE);
    }

    /**
     * Sets the {@code SETTINGS_INITIAL_WINDOW_SIZE} value.
     *
     * @throws IllegalArgumentException if verification of the setting fails.
     */
    public Http2Settings initialWindowSize(int value) {
        put(SETTINGS_INITIAL_WINDOW_SIZE, Long.valueOf(value));
        return this;
    }

    /**
     * Gets the {@code SETTINGS_MAX_FRAME_SIZE} value. If unavailable, returns {@code null}.
     */
    public Integer maxFrameSize() {
        return getIntValue(SETTINGS_MAX_FRAME_SIZE);
    }

    /**
     * Sets the {@code SETTINGS_MAX_FRAME_SIZE} value.
     *
     * @throws IllegalArgumentException if verification of the setting fails.
     */
    public Http2Settings maxFrameSize(int value) {
        put(SETTINGS_MAX_FRAME_SIZE, Long.valueOf(value));
        return this;
    }

    /**
     * Gets the {@code SETTINGS_MAX_HEADER_LIST_SIZE} value. If unavailable, returns {@code null}.
     */
    public Integer maxHeaderListSize() {
        Integer value = getIntValue(SETTINGS_MAX_HEADER_LIST_SIZE);

        // Over 2^31 - 1 (minus in integer) size is set to the maximun value
        if (value != null && value < 0) {
            value = Integer.MAX_VALUE;
        }

        return value;
    }

    /**
     * Sets the {@code SETTINGS_MAX_HEADER_LIST_SIZE} value.
     *
     * @throws IllegalArgumentException if verification of the setting fails.
     */
    public Http2Settings maxHeaderListSize(int value) {
        // Over 2^31 - 1 (minus in integer) size is set to the maximun value
        if (value < 0) {
            value = Integer.MAX_VALUE;
        }

        put(SETTINGS_MAX_HEADER_LIST_SIZE, Long.valueOf(value));
        return this;
    }

    /**
     * Clears and then copies the given settings into this object.
     */
    public Http2Settings copyFrom(Http2Settings settings) {
        clear();
        putAll(settings);
        return this;
    }

    /**
     * A helper method that returns {@link Long#intValue()} on the return of {@link #get(char)}, if present. Note that
     * if the range of the value exceeds {@link Integer#MAX_VALUE}, the {@link #get(char)} method should
     * be used instead to avoid truncation of the value.
     */
    public Integer getIntValue(char key) {
        Long value = get(key);
        if (value == null) {
            return null;
        }
        return value.intValue();
    }

    private static void verifyStandardSetting(int key, Long value) {
        checkNotNull(value, "value");
        switch (key) {
            case SETTINGS_HEADER_TABLE_SIZE:
                if (value < MIN_HEADER_TABLE_SIZE || value > MAX_HEADER_TABLE_SIZE) {
                    throw new IllegalArgumentException("Setting HEADER_TABLE_SIZE is invalid: " + value);
                }
                break;
            case SETTINGS_ENABLE_PUSH:
                if (value != 0L && value != 1L) {
                    throw new IllegalArgumentException("Setting ENABLE_PUSH is invalid: " + value);
                }
                break;
            case SETTINGS_MAX_CONCURRENT_STREAMS:
                if (value < MIN_CONCURRENT_STREAMS || value > MAX_CONCURRENT_STREAMS) {
                    throw new IllegalArgumentException(
                            "Setting MAX_CONCURRENT_STREAMS is invalid: " + value);
                }
                break;
            case SETTINGS_INITIAL_WINDOW_SIZE:
                if (value < MIN_INITIAL_WINDOW_SIZE || value > MAX_INITIAL_WINDOW_SIZE) {
                    throw new IllegalArgumentException("Setting INITIAL_WINDOW_SIZE is invalid: "
                            + value);
                }
                break;
            case SETTINGS_MAX_FRAME_SIZE:
                if (!isMaxFrameSizeValid(value.intValue())) {
                    throw new IllegalArgumentException("Setting MAX_FRAME_SIZE is invalid: " + value);
                }
                break;
            case SETTINGS_MAX_HEADER_LIST_SIZE:
                if (value < MIN_HEADER_LIST_SIZE || value > MAX_HEADER_LIST_SIZE) {
                    throw new IllegalArgumentException("Setting MAX_HEADER_LIST_SIZE is invalid: " + value);
                }
                break;
            default:
                // Non-standard HTTP/2 setting - don't do validation.
                break;
        }
    }

    @Override
    protected String keyToString(char key) {
        switch (key) {
            case SETTINGS_HEADER_TABLE_SIZE:
                return "HEADER_TABLE_SIZE";
            case SETTINGS_ENABLE_PUSH:
                return "ENABLE_PUSH";
            case SETTINGS_MAX_CONCURRENT_STREAMS:
                return "MAX_CONCURRENT_STREAMS";
            case SETTINGS_INITIAL_WINDOW_SIZE:
                return "INITIAL_WINDOW_SIZE";
            case SETTINGS_MAX_FRAME_SIZE:
                return "MAX_FRAME_SIZE";
            case SETTINGS_MAX_HEADER_LIST_SIZE:
                return "MAX_HEADER_LIST_SIZE";
            default:
                // Unknown keys.
                return super.keyToString(key);
        }
    }
}