Java/Regular Expressions/Lookup
Содержание
Java Regular Expression : File and Find
/* From http://java.sun.ru/docs/books/tutorial/index.html */
/*
* Copyright (c) 2006 Sun Microsystems, Inc. All Rights Reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* -Redistribution of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* -Redistribution in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* Neither the name of Sun Microsystems, Inc. or the names of contributors may
* be used to endorse or promote products derived from this software without
* specific prior written permission.
*
* This software is provided "AS IS," without a warranty of any kind. ALL
* EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING
* ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE
* OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN MIDROSYSTEMS, INC. ("SUN")
* AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE
* AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS
* DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR ANY LOST
* REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL,
* INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY
* OF LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE,
* EVEN IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
*
* You acknowledge that this software is not designed, licensed or intended
* for use in the design, construction, operation or maintenance of any
* nuclear facility.
*/
import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public final class RegexTestHarness {
private static String REGEX;
private static String INPUT;
private static BufferedReader br;
private static Pattern pattern;
private static Matcher matcher;
private static boolean found;
public static void main(String[] argv) {
initResources();
processTest();
closeResources();
}
private static void initResources() {
try {
br = new BufferedReader(new FileReader("regex.txt"));
} catch (FileNotFoundException fnfe) {
System.out
.println("Cannot locate input file! " + fnfe.getMessage());
System.exit(0);
}
try {
REGEX = br.readLine();
INPUT = br.readLine();
} catch (IOException ioe) {
}
pattern = Pattern.rupile(REGEX);
matcher = pattern.matcher(INPUT);
System.out.println("Current REGEX is: " + REGEX);
System.out.println("Current INPUT is: " + INPUT);
}
private static void processTest() {
while (matcher.find()) {
System.out.println("I found the text \"" + matcher.group()
+ "\" starting at index " + matcher.start()
+ " and ending at index " + matcher.end() + ".");
found = true;
}
if (!found) {
System.out.println("No match found.");
}
}
private static void closeResources() {
try {
br.close();
} catch (IOException ioe) {
}
}
}
Java Regular Expression : find 2
/* From http://java.sun.ru/docs/books/tutorial/index.html */
/*
* Copyright (c) 2006 Sun Microsystems, Inc. All Rights Reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* -Redistribution of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* -Redistribution in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* Neither the name of Sun Microsystems, Inc. or the names of contributors may
* be used to endorse or promote products derived from this software without
* specific prior written permission.
*
* This software is provided "AS IS," without a warranty of any kind. ALL
* EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING
* ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE
* OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN MIDROSYSTEMS, INC. ("SUN")
* AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE
* AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS
* DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR ANY LOST
* REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL,
* INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY
* OF LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE,
* EVEN IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
*
* You acknowledge that this software is not designed, licensed or intended
* for use in the design, construction, operation or maintenance of any
* nuclear facility.
*/
import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.util.regex.PatternSyntaxException;
public final class RegexTestHarness2 {
private static String REGEX;
private static String INPUT;
private static BufferedReader br;
private static Pattern pattern;
private static Matcher matcher;
private static boolean found;
public static void main(String[] argv) {
initResources();
processTest();
closeResources();
}
private static void initResources() {
try {
br = new BufferedReader(new FileReader("regex.txt"));
} catch (FileNotFoundException fnfe) {
System.out
.println("Cannot locate input file! " + fnfe.getMessage());
System.exit(0);
}
try {
REGEX = br.readLine();
INPUT = br.readLine();
} catch (IOException ioe) {
}
try {
pattern = Pattern.rupile(REGEX);
matcher = pattern.matcher(INPUT);
} catch (PatternSyntaxException pse) {
System.out
.println("There is a problem with the regular expression!");
System.out.println("The pattern in question is: "
+ pse.getPattern());
System.out.println("The description is: " + pse.getDescription());
System.out.println("The message is: " + pse.getMessage());
System.out.println("The index is: " + pse.getIndex());
System.exit(0);
}
System.out.println("Current REGEX is: " + REGEX);
System.out.println("Current INPUT is: " + INPUT);
}
private static void processTest() {
while (matcher.find()) {
System.out.println("I found the text \"" + matcher.group()
+ "\" starting at index " + matcher.start()
+ " and ending at index " + matcher.end() + ".");
found = true;
}
if (!found) {
System.out.println("No match found.");
}
}
private static void closeResources() {
try {
br.close();
} catch (IOException ioe) {
}
}
}
Negative Look ahead
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class NegativeLookaheadExample {
public static void main(String args[]) throws Exception {
String regex = "John (?!Smith)[A-Z]\\w+";
Pattern pattern = Pattern.rupile(regex);
String candidate = "I think that John Smith ";
candidate += "is a fictional character. His real name ";
candidate += "might be John Jackson, John Westling, ";
candidate += "or John Holmes for all we know.";
Matcher matcher = pattern.matcher(candidate);
String tmp = null;
while (matcher.find()) {
tmp = matcher.group();
System.out.println("MATCH:" + tmp);
}
}
}
Positive Look ahead
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class PositiveLookaheadExample {
public static void main(String args[]) {
String regex = "(?=^255).*";
Pattern pattern = Pattern.rupile(regex);
String candidate = "255.0.0.1";
Matcher matcher = pattern.matcher(candidate);
String ip = "not found";
if (matcher.find())
ip = matcher.group();
String msg = "ip: " + ip;
System.out.println(msg);
}
}
Positive Look behind 1
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class PositiveLookBehindExample {
public static void main(String args[]) throws Exception {
String regex = "(?<=http://)\\S+";
Pattern pattern = Pattern.rupile(regex);
String candidate = "The jexp website can be found at ";
candidate += "http://www.jexp.ru. There, ";
candidate += "you can find some Java examples.";
Matcher matcher = pattern.matcher(candidate);
while (matcher.find()) {
String msg = ":" + matcher.group() + ":";
System.out.println(msg);
}
}
}
Positive Look Behind 2
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class PositiveLookBehindExample {
public static void main(String args[]) throws Exception {
String regex = "(?<=http://)\\S+";
Pattern pattern = Pattern.rupile(regex);
String candidate = "The jexp website can be found at ";
candidate += "http://www.jexp.ru. There, ";
candidate += "you can find some best example code for Java.";
Matcher matcher = pattern.matcher(candidate);
while (matcher.find()) {
String msg = ":" + matcher.group() + ":";
System.out.println(msg);
}
}
}
Positive Look Behind 3
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class PositiveLookBehindExample {
public static void main(String args[]) throws Exception {
String regex = "(?<=http://)\\S+";
Pattern pattern = Pattern.rupile(regex);
String candidate = "The jexp website can be found at ";
candidate += "http://www.jexp.ru. There, ";
candidate += "you can find information about some of ";
candidate += "best example codes";
Matcher matcher = pattern.matcher(candidate);
while (matcher.find()) {
String msg = ":" + matcher.group() + ":";
System.out.println(msg);
}
}
}
Regular Expression: find
/* From http://java.sun.ru/docs/books/tutorial/index.html */
/*
* Copyright (c) 2006 Sun Microsystems, Inc. All Rights Reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* -Redistribution of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* -Redistribution in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* Neither the name of Sun Microsystems, Inc. or the names of contributors may
* be used to endorse or promote products derived from this software without
* specific prior written permission.
*
* This software is provided "AS IS," without a warranty of any kind. ALL
* EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING
* ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE
* OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN MIDROSYSTEMS, INC. ("SUN")
* AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE
* AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS
* DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR ANY LOST
* REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL,
* INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY
* OF LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE,
* EVEN IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
*
* You acknowledge that this software is not designed, licensed or intended
* for use in the design, construction, operation or maintenance of any
* nuclear facility.
*/
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public final class MatcherTest {
private static final String REGEX = "\\bdog\\b";
private static final String INPUT = "dog dog dog doggie dogg";
public static void main(String[] argv) {
Pattern p = Pattern.rupile(REGEX);
Matcher m = p.matcher(INPUT); // get a matcher object
int count = 0;
while (m.find()) {
count++;
System.out.println("Match number " + count);
System.out.println("start(): " + m.start());
System.out.println("end(): " + m.end());
}
}
}
