io.netty.handler.codec.http2.Http2Flags Maven / Gradle / Ivy
/*
* 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:
*
* https://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;
/**
* Provides utility methods for accessing specific flags as defined by the HTTP/2 spec.
*/
public final class Http2Flags {
public static final short END_STREAM = 0x1;
public static final short END_HEADERS = 0x4;
public static final short ACK = 0x1;
public static final short PADDED = 0x8;
public static final short PRIORITY = 0x20;
private short value;
public Http2Flags() {
}
public Http2Flags(short value) {
this.value = value;
}
/**
* Gets the underlying flags value.
*/
public short value() {
return value;
}
/**
* Determines whether the {@link #END_STREAM} flag is set. Only applies to DATA and HEADERS
* frames.
*/
public boolean endOfStream() {
return isFlagSet(END_STREAM);
}
/**
* Determines whether the {@link #END_HEADERS} flag is set. Only applies for HEADERS,
* PUSH_PROMISE, and CONTINUATION frames.
*/
public boolean endOfHeaders() {
return isFlagSet(END_HEADERS);
}
/**
* Determines whether the flag is set indicating the presence of the exclusive, stream
* dependency, and weight fields in a HEADERS frame.
*/
public boolean priorityPresent() {
return isFlagSet(PRIORITY);
}
/**
* Determines whether the flag is set indicating that this frame is an ACK. Only applies for
* SETTINGS and PING frames.
*/
public boolean ack() {
return isFlagSet(ACK);
}
/**
* For frames that include padding, indicates if the {@link #PADDED} field is present. Only
* applies to DATA, HEADERS, PUSH_PROMISE and CONTINUATION frames.
*/
public boolean paddingPresent() {
return isFlagSet(PADDED);
}
/**
* Gets the number of bytes expected for the priority fields of the payload. This is determined
* by the {@link #priorityPresent()} flag.
*/
public int getNumPriorityBytes() {
return priorityPresent() ? 5 : 0;
}
/**
* Gets the length in bytes of the padding presence field expected in the payload. This is
* determined by the {@link #paddingPresent()} flag.
*/
public int getPaddingPresenceFieldLength() {
return paddingPresent() ? 1 : 0;
}
/**
* Sets the {@link #END_STREAM} flag.
*/
public Http2Flags endOfStream(boolean endOfStream) {
return setFlag(endOfStream, END_STREAM);
}
/**
* Sets the {@link #END_HEADERS} flag.
*/
public Http2Flags endOfHeaders(boolean endOfHeaders) {
return setFlag(endOfHeaders, END_HEADERS);
}
/**
* Sets the {@link #PRIORITY} flag.
*/
public Http2Flags priorityPresent(boolean priorityPresent) {
return setFlag(priorityPresent, PRIORITY);
}
/**
* Sets the {@link #PADDED} flag.
*/
public Http2Flags paddingPresent(boolean paddingPresent) {
return setFlag(paddingPresent, PADDED);
}
/**
* Sets the {@link #ACK} flag.
*/
public Http2Flags ack(boolean ack) {
return setFlag(ack, ACK);
}
/**
* Generic method to set any flag.
* @param on if the flag should be enabled or disabled.
* @param mask the mask that identifies the bit for the flag.
* @return this instance.
*/
public Http2Flags setFlag(boolean on, short mask) {
if (on) {
value |= mask;
} else {
value &= ~mask;
}
return this;
}
/**
* Indicates whether or not a particular flag is set.
* @param mask the mask identifying the bit for the particular flag being tested
* @return {@code true} if the flag is set
*/
public boolean isFlagSet(short mask) {
return (value & mask) != 0;
}
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result + value;
return result;
}
@Override
public boolean equals(Object obj) {
if (this == obj) {
return true;
}
if (obj == null) {
return false;
}
if (getClass() != obj.getClass()) {
return false;
}
return value == ((Http2Flags) obj).value;
}
@Override
public String toString() {
StringBuilder builder = new StringBuilder();
builder.append("value = ").append(value).append(" (");
if (ack()) {
builder.append("ACK,");
}
if (endOfHeaders()) {
builder.append("END_OF_HEADERS,");
}
if (endOfStream()) {
builder.append("END_OF_STREAM,");
}
if (priorityPresent()) {
builder.append("PRIORITY_PRESENT,");
}
if (paddingPresent()) {
builder.append("PADDING_PRESENT,");
}
builder.append(')');
return builder.toString();
}
}