/*
* Copyright 1999-2010 University of Chicago
*
* 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 org.globus.net;
import java.io.IOException;
import org.globus.common.CoGProperties;
/**
* This class manages the port ranges. It keeps track of which
* ports are used and which ones are open.
*/
public class PortRange {
protected static final byte UNUSED = 0;
protected static final byte USED = 1;
private boolean portRange = false;
private int minPort, maxPort;
private byte [] ports;
private static PortRange tcpPortRange = null;
private static PortRange tcpSourcePortRange = null;
private static PortRange udpSourcePortRange = null;
protected PortRange() {
}
/**
* Returns PortRange instance for TCP listening sockets.
*
* @see #getTcpInstance()
*/
public static PortRange getInstance() {
return getTcpInstance();
}
/**
* Returns PortRange instance for TCP listening sockets.
* If the tcp.port.range property is set, the class
* will be initialized with the specified port ranges.
*
* @return PortRange the default instace of this class.
*/
public static synchronized PortRange getTcpInstance() {
if (tcpPortRange == null) {
tcpPortRange = new PortRange();
tcpPortRange.init(CoGProperties.getDefault().getTcpPortRange());
}
return tcpPortRange;
}
/**
* Returns PortRange instance for TCP source sockets.
* If the tcp.source.port.range property is set, the class
* will be initialized with the specified port ranges.
*
* @return PortRange the default instace of this class.
*/
public static synchronized PortRange getTcpSourceInstance() {
if (tcpSourcePortRange == null) {
tcpSourcePortRange = new PortRange();
tcpSourcePortRange.init(
CoGProperties.getDefault().getTcpSourcePortRange());
}
return tcpSourcePortRange;
}
/**
* Returns PortRange instance for UDP source sockets.
* If the udp.source.port.range property is set, the class
* will be initialized with the specified port ranges.
*
* @return PortRange the default instace of this class.
*/
public static synchronized PortRange getUdpSourceInstance() {
if (udpSourcePortRange == null) {
udpSourcePortRange = new PortRange();
udpSourcePortRange.init(
CoGProperties.getDefault().getUdpSourcePortRange());
}
return udpSourcePortRange;
}
/**
* Checks if the port range is set.
*
* @return true if the port range is set, false otherwise.
*/
public boolean isEnabled() {
return portRange;
}
/**
* Returns first available port.
*
* @param lastPortNumber port number to start finding the next
* available port from. Set it to 0 if
* called initialy.
* @return the next available port number from the lastPortNumber.
* @exception IOException if there is no more free ports available or
* if the lastPortNumber is incorrect.
*/
public synchronized int getFreePort(int lastPortNumber)
throws IOException {
int id = 0;
if (lastPortNumber != 0) {
id = lastPortNumber - minPort;
if (id < 0) {
throw new IOException("Port number out of range.");
}
}
for(int i=id;i<ports.length;i++) {
if (ports[i] == USED) continue;
return minPort+i;
}
throw new IOException("No free ports available.");
}
/**
* Sets the port number as used.
*
* @param portNumber port number
*/
public void setUsed(int portNumber) {
setPort(portNumber, USED);
}
/**
* Releases or frees the port number.
* (Mark it as unused)
*
* @param portNumber port number
*/
public void free(int portNumber) {
setPort(portNumber, UNUSED);
}
/**
* Checks if the port number if within port range. Does <b>not</b>
* check if it is a free, but only checks if it is within said range.
*/
public boolean isInRange(int portNumber) {
if ((minPort <= portNumber) && (maxPort >= portNumber)) {
return true;
}
return false;
}
private synchronized void setPort(int portNumber, byte type) {
int id = portNumber - minPort;
if (id < 0) {
throw new IllegalArgumentException("Port number out of range: " + portNumber);
}
ports[id] = type;
}
private void init(String portRangeStr) {
portRange = false;
if (portRangeStr == null) return ;
int pos = portRangeStr.indexOf(",");
if (pos == -1) {
throw new IllegalArgumentException("Missing comma in the port range property: " +
portRangeStr);
}
int min, max;
try {
min = Integer.parseInt(portRangeStr.substring(0, pos).trim());
} catch(Exception e) {
throw new IllegalArgumentException("The minimum port range value is invalid: " +
e.getMessage());
}
try {
max = Integer.parseInt(portRangeStr.substring(pos+1).trim());
} catch(Exception e) {
throw new IllegalArgumentException("The maximum port range value is invalid: " +
e.getMessage());
}
if (min >= max) {
throw new IllegalArgumentException("The minimum port range value is greater then " +
"the maximum port range value.");
}
minPort = min;
maxPort = max;
ports = new byte[ maxPort-minPort ];
portRange = true;
}
}