| /* |
| * Copyright (c) 1995, 2013, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * 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. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package java.net; |
| |
| /** |
| * This class represents a datagram packet. |
| * <p> |
| * Datagram packets are used to implement a connectionless packet |
| * delivery service. Each message is routed from one machine to |
| * another based solely on information contained within that packet. |
| * Multiple packets sent from one machine to another might be routed |
| * differently, and might arrive in any order. Packet delivery is |
| * not guaranteed. |
| * |
| * @author Pavani Diwanji |
| * @author Benjamin Renaud |
| * @since 1.0 |
| */ |
| public final |
| class DatagramPacket { |
| |
| /** |
| * Perform class initialization |
| */ |
| static { |
| java.security.AccessController.doPrivileged( |
| new java.security.PrivilegedAction<>() { |
| public Void run() { |
| System.loadLibrary("net"); |
| return null; |
| } |
| }); |
| init(); |
| } |
| |
| /* |
| * The fields of this class are package-private since DatagramSocketImpl |
| * classes needs to access them. |
| */ |
| byte[] buf; |
| int offset; |
| int length; |
| int bufLength; |
| InetAddress address; |
| int port; |
| |
| /** |
| * Constructs a {@code DatagramPacket} for receiving packets of |
| * length {@code length}, specifying an offset into the buffer. |
| * <p> |
| * The {@code length} argument must be less than or equal to |
| * {@code buf.length}. |
| * |
| * @param buf buffer for holding the incoming datagram. |
| * @param offset the offset for the buffer |
| * @param length the number of bytes to read. |
| * |
| * @since 1.2 |
| */ |
| public DatagramPacket(byte buf[], int offset, int length) { |
| setData(buf, offset, length); |
| this.address = null; |
| this.port = -1; |
| } |
| |
| /** |
| * Constructs a {@code DatagramPacket} for receiving packets of |
| * length {@code length}. |
| * <p> |
| * The {@code length} argument must be less than or equal to |
| * {@code buf.length}. |
| * |
| * @param buf buffer for holding the incoming datagram. |
| * @param length the number of bytes to read. |
| */ |
| public DatagramPacket(byte buf[], int length) { |
| this (buf, 0, length); |
| } |
| |
| /** |
| * Constructs a datagram packet for sending packets of length |
| * {@code length} with offset {@code ioffset}to the |
| * specified port number on the specified host. The |
| * {@code length} argument must be less than or equal to |
| * {@code buf.length}. |
| * |
| * @param buf the packet data. |
| * @param offset the packet data offset. |
| * @param length the packet data length. |
| * @param address the destination address. |
| * @param port the destination port number. |
| * @see java.net.InetAddress |
| * |
| * @since 1.2 |
| */ |
| public DatagramPacket(byte buf[], int offset, int length, |
| InetAddress address, int port) { |
| setData(buf, offset, length); |
| setAddress(address); |
| setPort(port); |
| } |
| |
| /** |
| * Constructs a datagram packet for sending packets of length |
| * {@code length} with offset {@code ioffset}to the |
| * specified port number on the specified host. The |
| * {@code length} argument must be less than or equal to |
| * {@code buf.length}. |
| * |
| * @param buf the packet data. |
| * @param offset the packet data offset. |
| * @param length the packet data length. |
| * @param address the destination socket address. |
| * @throws IllegalArgumentException if address type is not supported |
| * @see java.net.InetAddress |
| * |
| * @since 1.4 |
| */ |
| public DatagramPacket(byte buf[], int offset, int length, SocketAddress address) { |
| setData(buf, offset, length); |
| setSocketAddress(address); |
| } |
| |
| /** |
| * Constructs a datagram packet for sending packets of length |
| * {@code length} to the specified port number on the specified |
| * host. The {@code length} argument must be less than or equal |
| * to {@code buf.length}. |
| * |
| * @param buf the packet data. |
| * @param length the packet length. |
| * @param address the destination address. |
| * @param port the destination port number. |
| * @see java.net.InetAddress |
| */ |
| public DatagramPacket(byte buf[], int length, |
| InetAddress address, int port) { |
| this(buf, 0, length, address, port); |
| } |
| |
| /** |
| * Constructs a datagram packet for sending packets of length |
| * {@code length} to the specified port number on the specified |
| * host. The {@code length} argument must be less than or equal |
| * to {@code buf.length}. |
| * |
| * @param buf the packet data. |
| * @param length the packet length. |
| * @param address the destination address. |
| * @throws IllegalArgumentException if address type is not supported |
| * @since 1.4 |
| * @see java.net.InetAddress |
| */ |
| public DatagramPacket(byte buf[], int length, SocketAddress address) { |
| this(buf, 0, length, address); |
| } |
| |
| /** |
| * Returns the IP address of the machine to which this datagram is being |
| * sent or from which the datagram was received. |
| * |
| * @return the IP address of the machine to which this datagram is being |
| * sent or from which the datagram was received. |
| * @see java.net.InetAddress |
| * @see #setAddress(java.net.InetAddress) |
| */ |
| public synchronized InetAddress getAddress() { |
| return address; |
| } |
| |
| /** |
| * Returns the port number on the remote host to which this datagram is |
| * being sent or from which the datagram was received. |
| * |
| * @return the port number on the remote host to which this datagram is |
| * being sent or from which the datagram was received. |
| * @see #setPort(int) |
| */ |
| public synchronized int getPort() { |
| return port; |
| } |
| |
| /** |
| * Returns the data buffer. The data received or the data to be sent |
| * starts from the {@code offset} in the buffer, |
| * and runs for {@code length} long. |
| * |
| * @return the buffer used to receive or send data |
| * @see #setData(byte[], int, int) |
| */ |
| public synchronized byte[] getData() { |
| return buf; |
| } |
| |
| /** |
| * Returns the offset of the data to be sent or the offset of the |
| * data received. |
| * |
| * @return the offset of the data to be sent or the offset of the |
| * data received. |
| * |
| * @since 1.2 |
| */ |
| public synchronized int getOffset() { |
| return offset; |
| } |
| |
| /** |
| * Returns the length of the data to be sent or the length of the |
| * data received. |
| * |
| * @return the length of the data to be sent or the length of the |
| * data received. |
| * @see #setLength(int) |
| */ |
| public synchronized int getLength() { |
| return length; |
| } |
| |
| /** |
| * Set the data buffer for this packet. This sets the |
| * data, length and offset of the packet. |
| * |
| * @param buf the buffer to set for this packet |
| * |
| * @param offset the offset into the data |
| * |
| * @param length the length of the data |
| * and/or the length of the buffer used to receive data |
| * |
| * @exception NullPointerException if the argument is null |
| * |
| * @see #getData |
| * @see #getOffset |
| * @see #getLength |
| * |
| * @since 1.2 |
| */ |
| public synchronized void setData(byte[] buf, int offset, int length) { |
| /* this will check to see if buf is null */ |
| if (length < 0 || offset < 0 || |
| (length + offset) < 0 || |
| ((length + offset) > buf.length)) { |
| throw new IllegalArgumentException("illegal length or offset"); |
| } |
| this.buf = buf; |
| this.length = length; |
| this.bufLength = length; |
| this.offset = offset; |
| } |
| |
| /** |
| * Sets the IP address of the machine to which this datagram |
| * is being sent. |
| * @param iaddr the {@code InetAddress} |
| * @since 1.1 |
| * @see #getAddress() |
| */ |
| public synchronized void setAddress(InetAddress iaddr) { |
| address = iaddr; |
| } |
| |
| /** |
| * Sets the port number on the remote host to which this datagram |
| * is being sent. |
| * @param iport the port number |
| * @since 1.1 |
| * @see #getPort() |
| */ |
| public synchronized void setPort(int iport) { |
| if (iport < 0 || iport > 0xFFFF) { |
| throw new IllegalArgumentException("Port out of range:"+ iport); |
| } |
| port = iport; |
| } |
| |
| /** |
| * Sets the SocketAddress (usually IP address + port number) of the remote |
| * host to which this datagram is being sent. |
| * |
| * @param address the {@code SocketAddress} |
| * @throws IllegalArgumentException if address is null or is a |
| * SocketAddress subclass not supported by this socket |
| * |
| * @since 1.4 |
| * @see #getSocketAddress |
| */ |
| public synchronized void setSocketAddress(SocketAddress address) { |
| if (address == null || !(address instanceof InetSocketAddress)) |
| throw new IllegalArgumentException("unsupported address type"); |
| InetSocketAddress addr = (InetSocketAddress) address; |
| if (addr.isUnresolved()) |
| throw new IllegalArgumentException("unresolved address"); |
| setAddress(addr.getAddress()); |
| setPort(addr.getPort()); |
| } |
| |
| /** |
| * Gets the SocketAddress (usually IP address + port number) of the remote |
| * host that this packet is being sent to or is coming from. |
| * |
| * @return the {@code SocketAddress} |
| * @since 1.4 |
| * @see #setSocketAddress |
| */ |
| public synchronized SocketAddress getSocketAddress() { |
| return new InetSocketAddress(getAddress(), getPort()); |
| } |
| |
| /** |
| * Set the data buffer for this packet. With the offset of |
| * this DatagramPacket set to 0, and the length set to |
| * the length of {@code buf}. |
| * |
| * @param buf the buffer to set for this packet. |
| * |
| * @exception NullPointerException if the argument is null. |
| * |
| * @see #getLength |
| * @see #getData |
| * |
| * @since 1.1 |
| */ |
| public synchronized void setData(byte[] buf) { |
| if (buf == null) { |
| throw new NullPointerException("null packet buffer"); |
| } |
| this.buf = buf; |
| this.offset = 0; |
| this.length = buf.length; |
| this.bufLength = buf.length; |
| } |
| |
| /** |
| * Set the length for this packet. The length of the packet is |
| * the number of bytes from the packet's data buffer that will be |
| * sent, or the number of bytes of the packet's data buffer that |
| * will be used for receiving data. The length must be lesser or |
| * equal to the offset plus the length of the packet's buffer. |
| * |
| * @param length the length to set for this packet. |
| * |
| * @exception IllegalArgumentException if the length is negative |
| * of if the length is greater than the packet's data buffer |
| * length. |
| * |
| * @see #getLength |
| * @see #setData |
| * |
| * @since 1.1 |
| */ |
| public synchronized void setLength(int length) { |
| if ((length + offset) > buf.length || length < 0 || |
| (length + offset) < 0) { |
| throw new IllegalArgumentException("illegal length"); |
| } |
| this.length = length; |
| this.bufLength = this.length; |
| } |
| |
| /** |
| * Perform class load-time initializations. |
| */ |
| private static native void init(); |
| } |