Java tutorial
package hudson; import hudson.model.TaskListener; import hudson.model.Hudson; import static hudson.model.Hudson.isWindows; import hudson.util.IOException2; import hudson.util.QuotedStringTokenizer; import hudson.util.VariableResolver; import hudson.Proc.LocalProc; import org.apache.tools.ant.BuildException; import org.apache.tools.ant.Project; import org.apache.tools.ant.types.FileSet; import org.apache.tools.ant.taskdefs.Chmod; import org.apache.tools.ant.taskdefs.Copy; import org.apache.commons.lang.time.FastDateFormat; import org.kohsuke.stapler.Stapler; import org.jvnet.animal_sniffer.IgnoreJRERequirement; import javax.crypto.SecretKey; import javax.crypto.spec.SecretKeySpec; import java.io.BufferedReader; import java.io.ByteArrayInputStream; import java.io.ByteArrayOutputStream; import java.io.File; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.io.OutputStreamWriter; import java.io.Reader; import java.io.Writer; import java.io.PrintStream; import java.io.InputStreamReader; import java.io.FileInputStream; import java.io.UnsupportedEncodingException; import java.net.InetAddress; import java.net.UnknownHostException; import java.net.URI; import java.net.URISyntaxException; import java.nio.CharBuffer; import java.nio.charset.CharacterCodingException; import java.nio.charset.CharsetEncoder; import java.security.DigestInputStream; import java.security.MessageDigest; import java.security.NoSuchAlgorithmException; import java.text.NumberFormat; import java.text.ParseException; import java.util.ArrayList; import java.util.Collection; import java.util.List; import java.util.Locale; import java.util.Map; import java.util.ResourceBundle; import java.util.SimpleTimeZone; import java.util.StringTokenizer; import java.util.Arrays; import java.util.logging.Level; import java.util.logging.Logger; import java.util.regex.Matcher; import java.util.regex.Pattern; import java.nio.charset.Charset; /** * Various utility methods that don't have more proper home. * * @author Kohsuke Kawaguchi */ public class Util { // Constant number of milliseconds in various time units. private static final long ONE_SECOND_MS = 1000; private static final long ONE_MINUTE_MS = 60 * ONE_SECOND_MS; private static final long ONE_HOUR_MS = 60 * ONE_MINUTE_MS; private static final long ONE_DAY_MS = 24 * ONE_HOUR_MS; private static final long ONE_MONTH_MS = 30 * ONE_DAY_MS; private static final long ONE_YEAR_MS = 365 * ONE_DAY_MS; /** * Creates a filtered sublist. * @since 1.176 */ public static <T> List<T> filter(Iterable<?> base, Class<T> type) { List<T> r = new ArrayList<T>(); for (Object i : base) { if (type.isInstance(i)) r.add(type.cast(i)); } return r; } /** * Creates a filtered sublist. */ public static <T> List<T> filter(List<?> base, Class<T> type) { return filter((Iterable) base, type); } /** * Pattern for capturing variables. Either $xyz or ${xyz}, while ignoring "$$" */ private static final Pattern VARIABLE = Pattern.compile("\\$([A-Za-z0-9_]+|\\{[A-Za-z0-9_]+\\}|\\$)"); /** * Replaces the occurrence of '$key' by <tt>properties.get('key')</tt>. * * <p> * Unlike shell, undefined variables are left as-is (this behavior is the same as Ant.) * */ public static String replaceMacro(String s, Map<String, String> properties) { return replaceMacro(s, new VariableResolver.ByMap<String>(properties)); } /** * Replaces the occurrence of '$key' by <tt>resolver.get('key')</tt>. * * <p> * Unlike shell, undefined variables are left as-is (this behavior is the same as Ant.) */ public static String replaceMacro(String s, VariableResolver<String> resolver) { if (s == null) { return null; } int idx = 0; while (true) { Matcher m = VARIABLE.matcher(s); if (!m.find(idx)) return s; String key = m.group().substring(1); // escape the dollar sign or get the key to resolve String value; if (key.charAt(0) == '$') { value = "$"; } else { if (key.charAt(0) == '{') key = key.substring(1, key.length() - 1); value = resolver.resolve(key); } if (value == null) idx = m.end(); // skip this else { s = s.substring(0, m.start()) + value + s.substring(m.end()); idx = m.start() + value.length(); } } } /** * Loads the contents of a file into a string. */ public static String loadFile(File logfile) throws IOException { return loadFile(logfile, Charset.defaultCharset()); } public static String loadFile(File logfile, Charset charset) throws IOException { if (!logfile.exists()) return ""; StringBuilder str = new StringBuilder((int) logfile.length()); BufferedReader r = new BufferedReader(new InputStreamReader(new FileInputStream(logfile), charset)); char[] buf = new char[1024]; int len; while ((len = r.read(buf, 0, buf.length)) > 0) str.append(buf, 0, len); r.close(); return str.toString(); } /** * Deletes the contents of the given directory (but not the directory itself) * recursively. * * @throws IOException * if the operation fails. */ public static void deleteContentsRecursive(File file) throws IOException { File[] files = file.listFiles(); if (files == null) return; // the directory didn't exist in the first place for (File child : files) deleteRecursive(child); } private static void deleteFile(File f) throws IOException { if (!f.delete()) { if (!f.exists()) // we are trying to delete a file that no longer exists, so this is not an error return; // perhaps this file is read-only? makeWritable(f); /* on Unix both the file and the directory that contains it has to be writable for a file deletion to be successful. (Confirmed on Solaris 9) $ ls -la total 6 dr-xr-sr-x 2 hudson hudson 512 Apr 18 14:41 . dr-xr-sr-x 3 hudson hudson 512 Apr 17 19:36 .. -r--r--r-- 1 hudson hudson 469 Apr 17 19:36 manager.xml -rw-r--r-- 1 hudson hudson 0 Apr 18 14:41 x $ rm x rm: x not removed: Permission denied */ makeWritable(f.getParentFile()); if (!f.delete() && f.exists()) { // trouble-shooting. // see http://www.nabble.com/Sometimes-can%27t-delete-files-from-hudson.scm.SubversionSCM%24CheckOutTask.invoke%28%29-tt17333292.html // I suspect other processes putting files in this directory File[] files = f.listFiles(); if (files != null && files.length > 0) throw new IOException( "Unable to delete " + f.getPath() + " - files in dir: " + Arrays.asList(files)); throw new IOException("Unable to delete " + f.getPath()); } } } /** * Makes the given file writable. */ @IgnoreJRERequirement private static void makeWritable(File f) { // try chmod. this becomes no-op if this is not Unix. try { Chmod chmod = new Chmod(); chmod.setProject(new Project()); chmod.setFile(f); chmod.setPerm("u+w"); chmod.execute(); } catch (BuildException e) { LOGGER.log(Level.INFO, "Failed to chmod " + f, e); } // also try JDK6-way of doing it. try { f.setWritable(true); } catch (NoSuchMethodError e) { // not JDK6 } } public static void deleteRecursive(File dir) throws IOException { if (!isSymlink(dir)) deleteContentsRecursive(dir); deleteFile(dir); } /* * Copyright 2001-2004 The Apache Software Foundation. * * 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. */ /** * Checks if the given file represents a symlink. */ //Taken from http://svn.apache.org/viewvc/maven/shared/trunk/file-management/src/main/java/org/apache/maven/shared/model/fileset/util/FileSetManager.java?view=markup public static boolean isSymlink(File file) throws IOException { String name = file.getName(); if (name.equals(".") || name.equals("..")) return false; File fileInCanonicalParent = null; File parentDir = file.getParentFile(); if (parentDir == null) { fileInCanonicalParent = file; } else { fileInCanonicalParent = new File(parentDir.getCanonicalPath(), name); } return !fileInCanonicalParent.getCanonicalFile().equals(fileInCanonicalParent.getAbsoluteFile()); } /** * Creates a new temporary directory. */ public static File createTempDir() throws IOException { File tmp = File.createTempFile("hudson", "tmp"); if (!tmp.delete()) throw new IOException("Failed to delete " + tmp); if (!tmp.mkdirs()) throw new IOException("Failed to create a new directory " + tmp); return tmp; } private static final Pattern errorCodeParser = Pattern.compile(".*CreateProcess.*error=([0-9]+).*"); /** * On Windows, error messages for IOException aren't very helpful. * This method generates additional user-friendly error message to the listener */ public static void displayIOException(IOException e, TaskListener listener) { String msg = getWin32ErrorMessage(e); if (msg != null) listener.getLogger().println(msg); } public static String getWin32ErrorMessage(IOException e) { return getWin32ErrorMessage((Throwable) e); } /** * Extracts the Win32 error message from {@link Throwable} if possible. * * @return * null if there seems to be no error code or if the platform is not Win32. */ public static String getWin32ErrorMessage(Throwable e) { String msg = e.getMessage(); if (msg != null) { Matcher m = errorCodeParser.matcher(msg); if (m.matches()) { try { ResourceBundle rb = ResourceBundle.getBundle("/hudson/win32errors"); return rb.getString("error" + m.group(1)); } catch (Exception _) { // silently recover from resource related failures } } } if (e.getCause() != null) return getWin32ErrorMessage(e.getCause()); return null; // no message } /** * Gets a human readable message for the given Win32 error code. * * @return * null if no such message is available. */ public static String getWin32ErrorMessage(int n) { ResourceBundle rb = ResourceBundle.getBundle("/hudson/win32errors"); return rb.getString("error" + n); } /** * Guesses the current host name. */ public static String getHostName() { try { return InetAddress.getLocalHost().getHostName(); } catch (UnknownHostException e) { return "localhost"; } } public static void copyStream(InputStream in, OutputStream out) throws IOException { byte[] buf = new byte[8192]; int len; while ((len = in.read(buf)) > 0) out.write(buf, 0, len); } public static void copyStream(Reader in, Writer out) throws IOException { char[] buf = new char[8192]; int len; while ((len = in.read(buf)) > 0) out.write(buf, 0, len); } /** * Tokenizes the text separated by delimiters. * * <p> * In 1.210, this method was changed to handle quotes like Unix shell does. * Before that, this method just used {@link StringTokenizer}. * * @since 1.145 * @see QuotedStringTokenizer */ public static String[] tokenize(String s, String delimiter) { return QuotedStringTokenizer.tokenize(s, delimiter); } public static String[] tokenize(String s) { return tokenize(s, " \t\n\r\f"); } /** * Converts the map format of the environment variables to the K=V format in the array. */ public static String[] mapToEnv(Map<String, String> m) { String[] r = new String[m.size()]; int idx = 0; for (final Map.Entry<String, String> e : m.entrySet()) { r[idx++] = e.getKey() + '=' + e.getValue(); } return r; } public static int min(int x, int... values) { for (int i : values) { if (i < x) x = i; } return x; } public static String nullify(String v) { if (v != null && v.length() == 0) v = null; return v; } public static String removeTrailingSlash(String s) { if (s.endsWith("/")) return s.substring(0, s.length() - 1); else return s; } /** * Write-only buffer. */ private static final byte[] garbage = new byte[8192]; /** * Computes MD5 digest of the given input stream. * * @param source * The stream will be closed by this method at the end of this method. * @return * 32-char wide string */ public static String getDigestOf(InputStream source) throws IOException { try { MessageDigest md5 = MessageDigest.getInstance("MD5"); DigestInputStream in = new DigestInputStream(source, md5); try { while (in.read(garbage) > 0) ; // simply discard the input } finally { in.close(); } return toHexString(md5.digest()); } catch (NoSuchAlgorithmException e) { throw new IOException2("MD5 not installed", e); // impossible } } public static String getDigestOf(String text) { try { return getDigestOf(new ByteArrayInputStream(text.getBytes("UTF-8"))); } catch (IOException e) { throw new Error(e); } } /** * Converts a string into 128-bit AES key. * @since 1.308 */ public static SecretKey toAes128Key(String s) { try { // turn secretKey into 256 bit hash MessageDigest digest = MessageDigest.getInstance("SHA-256"); digest.reset(); digest.update(s.getBytes("UTF-8")); // Due to the stupid US export restriction JDK only ships 128bit version. return new SecretKeySpec(digest.digest(), 0, 128 / 8, "AES"); } catch (NoSuchAlgorithmException e) { throw new Error(e); } catch (UnsupportedEncodingException e) { throw new Error(e); } } public static String toHexString(byte[] data, int start, int len) { StringBuilder buf = new StringBuilder(); for (int i = 0; i < len; i++) { int b = data[start + i] & 0xFF; if (b < 16) buf.append('0'); buf.append(Integer.toHexString(b)); } return buf.toString(); } public static String toHexString(byte[] bytes) { return toHexString(bytes, 0, bytes.length); } public static byte[] fromHexString(String data) { byte[] r = new byte[data.length() / 2]; for (int i = 0; i < data.length(); i += 2) r[i / 2] = (byte) Integer.parseInt(data.substring(i, i + 2), 16); return r; } /** * Returns a human readable text of the time duration. * This version should be used for representing a duration of some activity (like build) * * @param duration * number of milliseconds. */ public static String getTimeSpanString(long duration) { // Break the duration up in to units. long years = duration / ONE_YEAR_MS; duration %= ONE_YEAR_MS; long months = duration / ONE_MONTH_MS; duration %= ONE_MONTH_MS; long days = duration / ONE_DAY_MS; duration %= ONE_DAY_MS; long hours = duration / ONE_HOUR_MS; duration %= ONE_HOUR_MS; long minutes = duration / ONE_MINUTE_MS; duration %= ONE_MINUTE_MS; long seconds = duration / ONE_SECOND_MS; duration %= ONE_SECOND_MS; long millisecs = duration; if (years > 0) return makeTimeSpanString(years, Messages.Util_year(years), months, Messages.Util_month(months)); else if (months > 0) return makeTimeSpanString(months, Messages.Util_month(months), days, Messages.Util_day(days)); else if (days > 0) return makeTimeSpanString(days, Messages.Util_day(days), hours, Messages.Util_hour(hours)); else if (hours > 0) return makeTimeSpanString(hours, Messages.Util_hour(hours), minutes, Messages.Util_minute(minutes)); else if (minutes > 0) return makeTimeSpanString(minutes, Messages.Util_minute(minutes), seconds, Messages.Util_second(seconds)); else if (seconds >= 10) return Messages.Util_second(seconds); else if (seconds >= 1) return Messages.Util_second(seconds + (float) (millisecs / 100) / 10); // render "1.2 sec" else if (millisecs >= 100) return Messages.Util_second((float) (millisecs / 10) / 100); // render "0.12 sec". else return Messages.Util_millisecond(millisecs); } /** * Create a string representation of a time duration. If the quantity of * the most significant unit is big (>=10), then we use only that most * significant unit in the string representation. If the quantity of the * most significant unit is small (a single-digit value), then we also * use a secondary, smaller unit for increased precision. * So 13 minutes and 43 seconds returns just "13 minutes", but 3 minutes * and 43 seconds is "3 minutes 43 seconds". */ private static String makeTimeSpanString(long bigUnit, String bigLabel, long smallUnit, String smallLabel) { String text = bigLabel; if (bigUnit < 10) text += ' ' + smallLabel; return text; } /** * Get a human readable string representing strings like "xxx days ago", * which should be used to point to the occurrence of an event in the past. */ public static String getPastTimeString(long duration) { return Messages.Util_pastTime(getTimeSpanString(duration)); } /** * Combines number and unit, with a plural suffix if needed. * * @deprecated * Use individual localization methods instead. * See {@link #Messages.Util_year(long)} for an example. * Deprecated since 2009-06-24, remove method after 2009-12-24. */ public static String combine(long n, String suffix) { String s = Long.toString(n) + ' ' + suffix; if (n != 1) // Just adding an 's' won't work in most natural languages, even English has exception to the rule (e.g. copy/copies). s += "s"; return s; } /** * Create a sub-list by only picking up instances of the specified type. */ public static <T> List<T> createSubList(Collection<?> source, Class<T> type) { List<T> r = new ArrayList<T>(); for (Object item : source) { if (type.isInstance(item)) r.add(type.cast(item)); } return r; } /** * Escapes non-ASCII characters in URL. * * <p> * Note that this methods only escapes non-ASCII but leaves other URL-unsafe characters, * such as '#'. * {@link #rawEncode(String)} should generally be used instead, though be careful to pass only * a single path component to that method (it will encode /, but this method does not). */ public static String encode(String s) { try { boolean escaped = false; StringBuilder out = new StringBuilder(s.length()); ByteArrayOutputStream buf = new ByteArrayOutputStream(); OutputStreamWriter w = new OutputStreamWriter(buf, "UTF-8"); for (int i = 0; i < s.length(); i++) { int c = (int) s.charAt(i); if (c < 128 && c != ' ') { out.append((char) c); } else { // 1 char -> UTF8 w.write(c); w.flush(); for (byte b : buf.toByteArray()) { out.append('%'); out.append(toDigit((b >> 4) & 0xF)); out.append(toDigit(b & 0xF)); } buf.reset(); escaped = true; } } return escaped ? out.toString() : s; } catch (IOException e) { throw new Error(e); // impossible } } /** * Encode a single path component for use in an HTTP URL. * Escapes all non-ASCII, general unsafe (space and "#%<>[\]^`{|}~) * and HTTP special characters (/;:?) as specified in RFC1738, * plus backslash (Windows path separator). * Note that slash(/) is encoded, so the given string should be a * single path component used in constructing a URL. * Method name inspired by PHP's rawencode. */ public static String rawEncode(String s) { boolean escaped = false; StringBuilder out = null; CharsetEncoder enc = null; CharBuffer buf = null; char c; for (int i = 0, m = s.length(); i < m; i++) { c = s.charAt(i); if ((c < 64 || c > 90) && (c < 97 || c > 122) && (c < 38 || c > 57 || c == 47) && c != 61 && c != 36 && c != 33 && c != 95) { if (!escaped) { out = new StringBuilder(i + (m - i) * 3); out.append(s.substring(0, i)); enc = Charset.forName("UTF-8").newEncoder(); buf = CharBuffer.allocate(1); escaped = true; } // 1 char -> UTF8 buf.put(0, c); buf.rewind(); try { for (byte b : enc.encode(buf).array()) { out.append('%'); out.append(toDigit((b >> 4) & 0xF)); out.append(toDigit(b & 0xF)); } } catch (CharacterCodingException ex) { } } else if (escaped) { out.append(c); } } return escaped ? out.toString() : s; } private static char toDigit(int n) { return (char) (n < 10 ? '0' + n : 'A' + n - 10); } /** * Surrounds by a single-quote. */ public static String singleQuote(String s) { return '\'' + s + '\''; } /** * Escapes HTML unsafe characters like <, & to the respective character entities. */ public static String escape(String text) { StringBuilder buf = new StringBuilder(text.length() + 64); for (int i = 0; i < text.length(); i++) { char ch = text.charAt(i); if (ch == '\n') buf.append("<br>"); else if (ch == '<') buf.append("<"); else if (ch == '&') buf.append("&"); else if (ch == ' ') { // All spaces in a block of consecutive spaces are converted to // non-breaking space ( ) except for the last one. This allows // significant whitespace to be retained without prohibiting wrapping. char nextCh = i + 1 < text.length() ? text.charAt(i + 1) : 0; buf.append(nextCh == ' ' ? " " : " "); } else buf.append(ch); } return buf.toString(); } public static String xmlEscape(String text) { StringBuilder buf = new StringBuilder(text.length() + 64); for (int i = 0; i < text.length(); i++) { char ch = text.charAt(i); if (ch == '<') buf.append("<"); else if (ch == '&') buf.append("&"); else buf.append(ch); } return buf.toString(); } /** * Creates an empty file. */ public static void touch(File file) throws IOException { new FileOutputStream(file).close(); } /** * Copies a single file by using Ant. */ public static void copyFile(File src, File dst) throws BuildException { Copy cp = new Copy(); cp.setProject(new org.apache.tools.ant.Project()); cp.setTofile(dst); cp.setFile(src); cp.setOverwrite(true); cp.execute(); } /** * Convert null to "". */ public static String fixNull(String s) { if (s == null) return ""; else return s; } /** * Convert empty string to null. */ public static String fixEmpty(String s) { if (s == null || s.length() == 0) return null; return s; } /** * Convert empty string to null, and trim whitespace. * * @since 1.154 */ public static String fixEmptyAndTrim(String s) { if (s == null) return null; return fixEmpty(s.trim()); } /** * Cuts all the leading path portion and get just the file name. */ public static String getFileName(String filePath) { int idx = filePath.lastIndexOf('\\'); if (idx >= 0) return getFileName(filePath.substring(idx + 1)); idx = filePath.lastIndexOf('/'); if (idx >= 0) return getFileName(filePath.substring(idx + 1)); return filePath; } /** * Concatenate multiple strings by inserting a separator. */ public static String join(Collection<String> strings, String seprator) { StringBuilder buf = new StringBuilder(); boolean first = true; for (String s : strings) { if (first) first = false; else buf.append(seprator); buf.append(s); } return buf.toString(); } /** * Combines all the given collections into a single list. */ public static <T> List<T> join(Collection<? extends T>... items) { int size = 0; for (Collection<? extends T> item : items) size += item.size(); List<T> r = new ArrayList<T>(size); for (Collection<? extends T> item : items) r.addAll(item); return r; } /** * Creates Ant {@link FileSet} with the base dir and include pattern. * * <p> * The difference with this and using {@link FileSet#setIncludes(String)} * is that this method doesn't treat whitespace as a pattern separator, * which makes it impossible to use space in the file path. * * @param includes * String like "foo/bar/*.xml" Multiple patterns can be separated * by ',', and whitespace can surround ',' (so that you can write * "abc, def" and "abc,def" to mean the same thing. * @param excludes * Exclusion pattern. Follows the same format as the 'includes' parameter. * Can be null. * @since 1.172 */ public static FileSet createFileSet(File baseDir, String includes, String excludes) { FileSet fs = new FileSet(); fs.setDir(baseDir); fs.setProject(new Project()); StringTokenizer tokens; tokens = new StringTokenizer(includes, ","); while (tokens.hasMoreTokens()) { String token = tokens.nextToken().trim(); fs.createInclude().setName(token); } if (excludes != null) { tokens = new StringTokenizer(excludes, ","); while (tokens.hasMoreTokens()) { String token = tokens.nextToken().trim(); fs.createExclude().setName(token); } } return fs; } public static FileSet createFileSet(File baseDir, String includes) { return createFileSet(baseDir, includes, null); } /** * Creates a symlink to baseDir+targetPath at baseDir+symlinkPath. * <p> * If there's a prior symlink at baseDir+symlinkPath, it will be overwritten. */ public static void createSymlink(File baseDir, String targetPath, String symlinkPath, TaskListener listener) throws InterruptedException { if (!isWindows() && !NO_SYMLINK) { try { // ignore a failure. new LocalProc(new String[] { "rm", "-rf", symlinkPath }, new String[0], listener.getLogger(), baseDir).join(); int r = new LocalProc(new String[] { "ln", "-s", targetPath, symlinkPath }, new String[0], listener.getLogger(), baseDir).join(); if (r != 0) listener.getLogger().println("ln failed: " + r); } catch (IOException e) { PrintStream log = listener.getLogger(); log.println("ln failed"); Util.displayIOException(e, listener); e.printStackTrace(log); } } } /** * Encodes the URL by RFC 2396. * * I thought there's another spec that refers to UTF-8 as the encoding, * but don't remember it right now. * * @since 1.204 * @deprecated This method is broken (see ISSUE#1666). It should probably * be removed but I'm not sure if it is considered part of the public API * that needs to be maintained for backwards compatibility. * Use {@link #encode(String)} instead. */ @Deprecated public static String encodeRFC2396(String url) { try { return new URI(null, url, null).toASCIIString(); } catch (URISyntaxException e) { LOGGER.warning("Failed to encode " + url); // could this ever happen? return url; } } /** * Wraps with the error icon and the CSS class to render error message. * @since 1.173 */ public static String wrapToErrorSpan(String s) { s = "<span class=error><img src='" + Stapler.getCurrentRequest().getContextPath() + Hudson.RESOURCE_PATH + "/images/none.gif' height=16 width=1>" + s + "</span>"; return s; } /** * Returns the parsed string if parsed successful; otherwise returns the default number. * If the string is null, empty or a ParseException is thrown then the defaultNumber * is returned. * @param numberStr string to parse * @param defaultNumber number to return if the string can not be parsed * @return returns the parsed string; otherwise the default number */ public static Number tryParseNumber(String numberStr, Number defaultNumber) { if ((numberStr == null) || (numberStr.length() == 0)) { return defaultNumber; } try { return NumberFormat.getNumberInstance().parse(numberStr); } catch (ParseException e) { return defaultNumber; } } /** * Checks if the public method defined on the base type with the given arguments * are overridden in the given derived type. */ public static boolean isOverridden(Class base, Class derived, String methodName, Class... types) { // the rewriteHudsonWar method isn't overridden. try { return !base.getMethod(methodName, types).equals(derived.getMethod(methodName, types)); } catch (NoSuchMethodException e) { throw new AssertionError(e); } } public static final FastDateFormat XS_DATETIME_FORMATTER = FastDateFormat .getInstance("yyyy-MM-dd'T'HH:mm:ss'Z'", new SimpleTimeZone(0, "GMT")); // Note: RFC822 dates must not be localized! public static final FastDateFormat RFC822_DATETIME_FORMATTER = FastDateFormat .getInstance("EEE, dd MMM yyyy HH:mm:ss Z", Locale.US); private static final Logger LOGGER = Logger.getLogger(Util.class.getName()); /** * On Unix environment that cannot run "ln", set this to true. */ public static boolean NO_SYMLINK = Boolean.getBoolean(Util.class.getName() + ".noSymLink"); }