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20 package org.apache.mina.util;
21
22 import java.io.IOException;
23 import java.net.DatagramSocket;
24 import java.net.ServerSocket;
25 import java.util.NoSuchElementException;
26 import java.util.Set;
27 import java.util.TreeSet;
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34
35 public class AvailablePortFinder {
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37
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39 public static final int MIN_PORT_NUMBER = 1;
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44 public static final int MAX_PORT_NUMBER = 49151;
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46
47
48
49 private AvailablePortFinder() {
50
51 }
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60 public static Set<Integer> getAvailablePorts() {
61 return getAvailablePorts(MIN_PORT_NUMBER, MAX_PORT_NUMBER);
62 }
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67
68
69 public static int getNextAvailable() {
70 try {
71
72 return new ServerSocket( 0 ).getLocalPort();
73 } catch (IOException ioe) {
74 throw new NoSuchElementException(ioe.getMessage());
75 }
76 }
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83
84 public static int getNextAvailable(int fromPort) {
85 if (fromPort < MIN_PORT_NUMBER || fromPort > MAX_PORT_NUMBER) {
86 throw new IllegalArgumentException("Invalid start port: "
87 + fromPort);
88 }
89
90 for (int i = fromPort; i <= MAX_PORT_NUMBER; i++) {
91 if (available(i)) {
92 return i;
93 }
94 }
95
96 throw new NoSuchElementException("Could not find an available port "
97 + "above " + fromPort);
98 }
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105 public static boolean available(int port) {
106 if (port < MIN_PORT_NUMBER || port > MAX_PORT_NUMBER) {
107 throw new IllegalArgumentException("Invalid start port: " + port);
108 }
109
110 ServerSocket ss = null;
111 DatagramSocket ds = null;
112 try {
113 ss = new ServerSocket(port);
114 ss.setReuseAddress(true);
115 ds = new DatagramSocket(port);
116 ds.setReuseAddress(true);
117 return true;
118 } catch (IOException e) {
119
120 } finally {
121 if (ds != null) {
122 ds.close();
123 }
124
125 if (ss != null) {
126 try {
127 ss.close();
128 } catch (IOException e) {
129
130 }
131 }
132 }
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134 return false;
135 }
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145 public static Set<Integer> getAvailablePorts(int fromPort, int toPort) {
146 if (fromPort < MIN_PORT_NUMBER || toPort > MAX_PORT_NUMBER
147 || fromPort > toPort) {
148 throw new IllegalArgumentException("Invalid port range: "
149 + fromPort + " ~ " + toPort);
150 }
151
152 Set<Integer> result = new TreeSet<Integer>();
153
154 for (int i = fromPort; i <= toPort; i++) {
155 ServerSocket s = null;
156
157 try {
158 s = new ServerSocket(i);
159 result.add(new Integer(i));
160 } catch (IOException e) {
161
162 } finally {
163 if (s != null) {
164 try {
165 s.close();
166 } catch (IOException e) {
167
168 }
169 }
170 }
171 }
172
173 return result;
174 }
175 }