Util.java revision 1185
304N/A/*
304N/A * CDDL HEADER START
304N/A *
304N/A * The contents of this file are subject to the terms of the
304N/A * Common Development and Distribution License (the "License").
304N/A * You may not use this file except in compliance with the License.
304N/A *
304N/A * See LICENSE.txt included in this distribution for the specific
304N/A * language governing permissions and limitations under the License.
304N/A *
304N/A * When distributing Covered Code, include this CDDL HEADER in each
304N/A * file and include the License file at LICENSE.txt.
304N/A * If applicable, add the following below this CDDL HEADER, with the
304N/A * fields enclosed by brackets "[]" replaced with your own identifying
304N/A * information: Portions Copyright [yyyy] [name of copyright owner]
304N/A *
304N/A * CDDL HEADER END
304N/A */
304N/A/*
304N/A * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
304N/A * Portions Copyright 2011 Jens Elkner.
304N/A */
304N/Apackage org.opensolaris.opengrok.web;
304N/A
304N/Aimport java.io.File;
304N/Aimport java.io.FileInputStream;
304N/Aimport java.io.FileReader;
304N/Aimport java.io.IOException;
304N/Aimport java.io.InputStreamReader;
304N/Aimport java.io.Reader;
304N/Aimport java.io.UnsupportedEncodingException;
304N/Aimport java.io.Writer;
304N/Aimport java.net.URI;
304N/Aimport java.net.URISyntaxException;
304N/Aimport java.net.URLEncoder;
304N/Aimport java.text.DecimalFormat;
304N/Aimport java.text.NumberFormat;
304N/Aimport java.util.Collection;
304N/Aimport java.util.LinkedList;
304N/Aimport java.util.logging.Level;
304N/Aimport java.util.zip.GZIPInputStream;
304N/A
304N/Aimport org.opensolaris.opengrok.Info;
304N/Aimport org.opensolaris.opengrok.OpenGrokLogger;
304N/Aimport org.opensolaris.opengrok.configuration.RuntimeEnvironment;
304N/Aimport org.opensolaris.opengrok.history.Annotation;
304N/Aimport org.opensolaris.opengrok.history.HistoryException;
304N/Aimport org.opensolaris.opengrok.history.HistoryGuru;
304N/A
304N/A/**
304N/A * Class for useful functions.
304N/A */
public final class Util {
private Util() {
// singleton
}
/**
* Return a string which represents a <code>CharSequence</code> in HTML.
*
* @param q
* a character sequence
* @return a string representing the character sequence in HTML
*/
public static String htmlize(CharSequence q) {
StringBuilder sb = new StringBuilder(q.length() * 2);
htmlize(q, sb);
return sb.toString();
}
/**
* Append a character sequence to the given destination whereby
* special characters for HTML are escaped accordingly.
*
* @param q a character sequence to esacpe
* @param dest where to append the character sequence to
*/
public static void htmlize(CharSequence q, StringBuilder dest) {
for (int i = 0; i < q.length(); i++ ) {
htmlize(q.charAt(i), dest);
}
}
/**
* Append a character array to the given destination whereby
* special characters for HTML are escaped accordingly.
*
* @param cs characters to esacpe
* @param length max. number of characters to append, starting from index 0.
* @param dest where to append the character sequence to
*/
public static void htmlize(char[] cs, int length, StringBuilder dest) {
if (cs.length < length) {
length = cs.length;
}
for (int i = 0; i < length; i++ ) {
htmlize(cs[i], dest);
}
}
/**
* Append a character to the given destination whereby special characters
* special for HTML are escaped accordingly.
*
* @param c the character to append
* @param dest where to append the character to
*/
private static final void htmlize(char c, StringBuilder dest) {
switch (c) {
case '&':
dest.append("&amp;");
break;
case '>':
dest.append("&gt;");
break;
case '<':
dest.append("&lt;");
break;
case '\n':
dest.append("<br/>");
break;
default:
dest.append(c);
}
}
private static String versionP = htmlize(Info.getRevision());
/**
* used by BUI - CSS needs this parameter for proper cache refresh (per
* changeset) in client browser jel: but useless, since the page cached
* anyway.
*
* @return html escaped version (hg changeset)
*/
public static String versionParameter() {
return versionP;
}
/**
* Convinience method for {@code breadcrumbPath(urlPrefix, path, '/')}.
* @param urlPrefix prefix to add to each url
* @param path path to crack
* @return HTML markup fro the breadcrumb or the path itself.
*
* @see #breadcrumbPath(String, String, char)
*/
public static String breadcrumbPath(String urlPrefix, String path) {
return breadcrumbPath(urlPrefix, path, '/');
}
private static final String anchorLinkStart = "<a href=\"";
private static final String anchorClassStart = "<a class=\"";
private static final String anchorEnd = "</a>";
private static final String closeQuotedTag = "\">";
/**
* Convinience method for
* {@code breadcrumbPath(urlPrefix, path, sep, "", false)}.
*
* @param urlPrefix prefix to add to each url
* @param path path to crack
* @param sep separator to use to crack the given path
*
* @return HTML markup fro the breadcrumb or the path itself.
* @see #breadcrumbPath(String, String, char, String, boolean, boolean)
*/
public static String breadcrumbPath(String urlPrefix, String path, char sep)
{
return breadcrumbPath(urlPrefix, path, sep, "", false);
}
/**
* Convinience method for
* {@code breadcrumbPath(urlPrefix, path, sep, "", false, path.endsWith(sep)}.
*
* @param urlPrefix prefix to add to each url
* @param path path to crack
* @param sep separator to use to crack the given path
* @param urlPostfix suffix to add to each url
* @param compact if {@code true} the given path gets transformed into
* its canonical form (.i.e. all '.' and '..' and double separators
* removed, but not always resolves to an absolute path) before processing
* starts.
* @return HTML markup fro the breadcrumb or the path itself.
* @see #breadcrumbPath(String, String, char, String, boolean, boolean)
* @see #getCanonicalPath(String, char)
*/
public static String breadcrumbPath(String urlPrefix, String path,
char sep, String urlPostfix, boolean compact)
{
if (path == null || path.length() == 0) {
return path;
}
return breadcrumbPath(urlPrefix, path, sep, urlPostfix, compact,
path.charAt(path.length() - 1) == sep);
}
/**
* Create a breadcrumb path to allow navigation to each element of a path.
* Consecutive separators (<var>sep</var>) in the given <var>path</var> are
* always collapsed into a single separator automatically. If
* <var>compact</var> is {@code true} path gets translated into a canonical
* path similar to {@link File#getCanonicalPath()}, however the current
* working directory is assumed to be "/" and no checks are done (e.g.
* neither whether the path [component] exists nor which type it is).
*
* @param urlPrefix
* what should be prepend to the constructed URL
* @param path
* the full path from which the breadcrumb path is built.
* @param sep
* the character that separates the path components in
* <var>path</var>
* @param urlPostfix
* what should be append to the constructed URL
* @param compact
* if {@code true}, a canonical path gets constructed before
* processing.
* @param isDir
* if {@code true} a "/" gets append to the last path component's
* link and <var>sep</var> to its name
* @return <var>path</var> if it resolves to an empty or "/" or
* {@code null} path, the HTML markup for the breadcrumb path otherwise.
*/
public static String breadcrumbPath(String urlPrefix, String path,
char sep, String urlPostfix, boolean compact, boolean isDir)
{
if (path == null || path.length() == 0) {
return path;
}
String[] pnames = normalize(path.split(escapeForRegex(sep)), compact);
if (pnames.length == 0) {
return path;
}
if (urlPrefix == null) {
urlPrefix = "";
}
if (urlPostfix == null) {
urlPostfix = "";
}
StringBuilder pwd = new StringBuilder(path.length() + pnames.length);
StringBuilder markup =
new StringBuilder( (pnames.length + 3 >> 1) * path.length()
+ pnames.length
* (17 + urlPrefix.length() + urlPostfix.length()));
int k = path.indexOf(pnames[0]);
if (path.lastIndexOf(sep, k) != -1) {
pwd.append('/');
markup.append(sep);
}
for (int i = 0; i < pnames.length; i++ ) {
pwd.append(URIEncodePath(pnames[i]));
if (isDir || i < pnames.length - 1) {
pwd.append('/');
}
markup.append(anchorLinkStart).append(urlPrefix).append(pwd)
.append(urlPostfix).append(closeQuotedTag).append(pnames[i])
.append(anchorEnd);
if (isDir || i < pnames.length - 1) {
markup.append(sep);
}
}
return markup.toString();
}
/**
* Normalize the given <var>path</var> to its canonical form. I.e. all
* separators (<var>sep</var>) are replaced with a slash ('/'), all
* double slashes are replaced by a single slash, all single dot path
* components (".") of the formed path are removed and all double dot path
* components (".." ) of the formed path are replaced with its parent or
* '/' if there is no parent.
* <p>
* So the difference to {@link File#getCanonicalPath()} is, that this method
* does not hit the disk (just string manipulation), resolves <var>path</var>
* always against '/' and thus always returns an absolute path, which may
* actually not exist, and which has a single trailing '/' if the given
* <var>path</var> ends with the given <var>sep</var>.
*
* @param path path to mangle. If not absolute or {@code null}, the
* current working directory is assumed to be '/'.
* @param sep file separator to use to crack <var>path</var> into path
* components
* @return always a canonical path which starts with a '/'.
*/
public static String getCanonicalPath(String path, char sep) {
if (path == null || path.length() == 0) {
return "/";
}
String[] pnames = normalize(path.split(escapeForRegex(sep)), true);
if (pnames.length == 0) {
return "/";
}
StringBuilder buf = new StringBuilder(path.length());
buf.append('/');
for (int i=0; i < pnames.length; i++) {
buf.append(pnames[i]).append('/');
}
if (path.charAt(path.length()-1) != sep) {
// since is not a general purpose method. So we waive to handle
// cases like:
// || path.endsWith("/..") || path.endsWith("/.")
buf.setLength(buf.length()-1);
}
return buf.toString();
}
/**
* Remove all empty and {@code null} string elements from the given
* <var>names</var> and optionally all redundant information like "." and
* "..".
*
* @param names
* names to check
* @param canonical
* if {@code true}, remove redundant elements as well.
* @return a possible empty array of names all with a length &gt; 0.
*/
private static String[] normalize(String[] names, boolean canonical) {
LinkedList<String> res = new LinkedList<String>();
if (names == null || names.length == 0) {
return new String[0];
}
for (int i = 0; i < names.length; i++ ) {
if (names[i] == null || names[i].length() == 0) {
continue;
}
if (canonical) {
if (names[i].equals("..")) {
if (res.size() > 0) {
res.removeLast();
}
} else if (names[i].equals(".")) {
continue;
} else {
res.add(names[i]);
}
} else {
res.add(names[i]);
}
}
return res.size() == names.length ? names : res.toArray(new String[res
.size()]);
}
/**
* Generate a regex that matches the specified character. Escape it in case
* it is a character that has a special meaning in a regex.
*
* @param c
* the character that the regex should match
* @return a six-character string on the form <tt>&#92;u</tt><i>hhhh</i>
*/
private static String escapeForRegex(char c) {
StringBuilder sb = new StringBuilder(6);
sb.append("\\u");
String hex = Integer.toHexString(c);
for (int i = 0; i < 4 - hex.length(); i++ ) {
sb.append('0');
}
sb.append(hex);
return sb.toString();
}
static NumberFormat FORMATTER = new DecimalFormat("#,###,###,###.#");
/**
* Convert the given size into a human readable string.
* @param num size to convert.
* @return a readable string
*/
public static String readableSize(long num) {
float l = num;
NumberFormat formatter = (NumberFormat) FORMATTER.clone();
if (l < 1024) {
return formatter.format(l) + ' '; // for none-dirs append 'B'? ...
} else if (l < 1048576) {
return (formatter.format(l / 1024) + " KiB");
} else {
return ("<b>" + formatter.format(l / 1048576) + " MiB</b>");
}
}
/**
* Converts different html special characters into their encodings used in
* html. Currently used only for tooltips of annotation revision number view
*
* @param s
* input text
* @return encoded text for use in <a title=""> tag
*/
public static String encode(String s) {
StringBuffer sb = new StringBuffer();
for (int i = 0; i < s.length(); i++ ) {
char c = s.charAt(i);
switch (c) {
case '"':
sb.append('\'');
break; // \\\"
case '&':
sb.append("&amp;");
break;
case '>':
sb.append("&gt;");
break;
case '<':
sb.append("&lt;");
break;
case ' ':
sb.append("&nbsp;");
break;
case '\t':
sb.append("&nbsp;&nbsp;&nbsp;&nbsp;");
break;
case '\n':
sb.append("&lt;br/&gt;");
break;
case '\r':
break;
default:
sb.append(c);
break;
}
}
return sb.toString();
}
/**
* Write out line information wrt. to the given annotation in the format:
* {@code Linenumber Blame Author} incl. appropriate links.
*
* @param num linenumber to print
* @param out print destination
* @param annotation annotation to use. If {@code null} only the
* linenumber gets printed.
* @param userPageLink see {@link RuntimeEnvironment#getUserPage()}
* @param userPageSuffix see {@link RuntimeEnvironment#getUserPageSuffix()}
* @throws IOException depends on the destination (<var>out</var>).
*/
public static void readableLine(int num, Writer out, Annotation annotation,
String userPageLink, String userPageSuffix)
throws IOException
{
// this method should go to JFlexXref
String snum = String.valueOf(num);
if (num > 1) {
out.write("\n");
}
out.write(anchorClassStart);
out.write( (num % 10 == 0 ? "hl" : "l"));
out.write("\" name=\"");
out.write(snum);
out.write("\" href=\"#");
out.write(snum);
out.write(closeQuotedTag);
out.write(snum);
out.write(anchorEnd);
if (annotation != null) {
String r = annotation.getRevision(num);
boolean enabled = annotation.isEnabled(num);
out.write("<span class=\"blame\">");
if (enabled) {
out.write(anchorClassStart);
out.write("r\" href=\"" );
out.write(URIEncode(annotation.getFilename()));
out.write("?a=true&amp;r=");
out.write(URIEncode(r));
String msg = annotation.getDesc(r);
if (msg != null) {
out.write("\" title=\"");
out.write(msg);
}
out.write(closeQuotedTag);
}
StringBuilder buf = new StringBuilder();
htmlize(r, buf);
out.write(buf.toString());
buf.setLength(0);
if (enabled) {
out.write(anchorEnd);
}
String a = annotation.getAuthor(num);
if (userPageLink != null) {
out.write(anchorClassStart);
out.write("a\" href=\"");
out.write(userPageLink);
out.write(URIEncode(a));
if (userPageSuffix != null) {
out.write(userPageSuffix);
}
out.write(closeQuotedTag);
htmlize(a, buf);
out.write(buf.toString());
buf.setLength(0);
out.write(anchorEnd);
} else {
out.write("<span class=\"a\">");
htmlize(a, buf);
out.write(buf.toString());
out.write("</span>");
buf.setLength(0);
}
out.write("</span>");
}
}
/**
* Generate a string from the given path and date in a way that allows
* stable lexicographic sorting (i.e. gives always the same results) as a
* walk of the file hierarchy. Thus null character (\u0000) is used both
* to separate directory components and to separate the path from the date.
* @param path path to mangle.
* @param date date string to use.
* @return the mangled path.
*/
public static String path2uid(String path, String date) {
return path.replace('/', '\u0000') + "\u0000" + date;
}
/**
* The reverse operation for {@link #path2uid(String, String)} - re-creates
* the unmangled path from the given uid.
* @param uid uid to unmangle.
* @return the original path.
*/
public static String uid2url(String uid) {
String url = uid.replace('\u0000', '/');
return url.substring(0, url.lastIndexOf('/')); // remove date from end
}
/**
* wrapper arround UTF-8 URL encoding of a string
*
* @param q query to be encoded. If {@code null}, an empty string will
* be used instead.
* @return null if fail, otherwise the encoded string
* @see URLEncoder#encode(String, String)
*/
public static String URIEncode(String q) {
try {
return q == null ? "" : URLEncoder.encode(q, "UTF-8");
} catch (UnsupportedEncodingException e) {
// Should not happen. UTF-8 must be supported by JVMs.
}
return null;
}
/**
* Append '&amp;name=value" to the given buffer. If the given <var>value</var>
* is {@code null}, this method does nothing.
*
* @param buf where to append the query string
* @param key the name of the parameter to add. Append as is!
* @param value the value for the given parameter. Gets automatically UTF-8
* URL encoded.
* @throws NullPointerException if the given buffer is {@code null}.
* @see #URIEncode(String)
*/
public static final void appendQuery(StringBuilder buf, String key,
String value)
{
if (value != null) {
buf.append("&amp;").append(key).append('=').append(URIEncode(value));
}
}
/**
* URI encode the given path.
* @param path path to encode.
* @return the encoded path.
* @see URI#getRawPath()
* @throws NullPointerException if a parameter is {@code null}
*/
public static String URIEncodePath(String path) {
try {
URI uri = new URI(null, null, path, null);
return uri.getRawPath();
} catch (URISyntaxException ex) {
OpenGrokLogger.getLogger().log(Level.WARNING,
"Could not encode path " + path, ex);
}
return "";
}
/**
* Replace all quote characters (ASCI 0x22) with the corresponding html
* entity (&amp;quot;).
* @param q string to escape.
* @return an empty string if a parameter is {@code null}, the mangled
* string otherwise.
*/
public static String formQuoteEscape(String q) {
if (q == null || q.isEmpty()) {
return "";
}
StringBuilder sb = new StringBuilder();
char c;
for (int i = 0; i < q.length(); i++ ) {
c = q.charAt(i);
if (c == '"') {
sb.append("&quot;");
} else {
sb.append(c);
}
}
return sb.toString();
}
private static final String SPAN_D = "<span class=\"d\">";
private static final String SPAN_A = "<span class=\"a\">";
private static final String SPAN_E = "</span>";
private static final int SPAN_LEN = SPAN_D.length() + SPAN_E.length();
/**
* Tag changes in the given <var>line1</var> and <var>line2</var>
* for highlighting. Removed parts are tagged with CSS class {@code d},
* new parts are tagged with CSS class {@code a} using a {@code span}
* element.
*
* @param line1 line of the original file
* @param line2 line of the changed/new file
* @return the tagged lines (field[0] ~= line1, field[1] ~= line2).
* @throws NullPointerException if one of the given parameters is {@code null}.
*/
public static String[] diffline(StringBuilder line1, StringBuilder line2) {
int m = line1.length();
int n = line2.length();
if (n == 0 || m == 0) {
return new String[] { line1.toString(), line2.toString() };
}
int s = 0;
char[] csl1 = new char[m + SPAN_LEN];
line1.getChars(0, m--, csl1, 0);
char[] csl2 = new char[n + SPAN_LEN];
line2.getChars(0, n--, csl2, 0);
while (s <= m && s <= n && csl1[s] == csl2[s]) {
s++ ;
}
while (s <= m && s <= n && csl1[m] == csl2[n]) {
m-- ;
n-- ;
}
String[] ret = new String[2];
// deleted
if (s <= m) {
m++;
System.arraycopy(csl1, m, csl1, m + SPAN_LEN, line1.length() - m);
System.arraycopy(csl1, s, csl1, s + SPAN_D.length(), m - s);
SPAN_E.getChars(0, SPAN_E.length(), csl1, m + SPAN_D.length());
SPAN_D.getChars(0, SPAN_D.length(), csl1, s);
ret[0] = new String(csl1);
} else {
ret[0] = line1.toString();
}
// added
if (s <= n) {
n++;
System.arraycopy(csl2, n, csl2, n + SPAN_LEN, line2.length() - n);
System.arraycopy(csl2, s, csl2, s + SPAN_A.length(), n - s);
SPAN_E.getChars(0, SPAN_E.length(), csl2, n + SPAN_A.length());
SPAN_A.getChars(0, SPAN_A.length(), csl2, s);
ret[1] = new String(csl2);
} else {
ret[1] = line2.toString();
}
return ret;
}
/**
* Dump the configuration as an HTML table.
*
* @param out
* destination for the HTML output
* @throws IOException
* if an error happens while writing to {@code out}
* @throws HistoryException
* if the history guru cannot be accesses
*/
@SuppressWarnings("boxing")
public static void dumpConfiguration(Appendable out) throws IOException,
HistoryException
{
out.append("<table border=\"1\" width=\"100%\">");
out.append("<tr><th>Variable</th><th>Value</th></tr>");
RuntimeEnvironment env = RuntimeEnvironment.getInstance();
printTableRow(out, "Source root", env.getSourceRootPath());
printTableRow(out, "Data root", env.getDataRootPath());
printTableRow(out, "CTags", env.getCtags());
printTableRow(out, "Bug page", env.getBugPage());
printTableRow(out, "Bug pattern", env.getBugPattern());
printTableRow(out, "User page", env.getUserPage());
printTableRow(out, "Review page", env.getReviewPage());
printTableRow(out, "Review pattern", env.getReviewPattern());
printTableRow(out, "Using projects", env.hasProjects());
out.append("<tr><td>Ignored files</td><td>");
printUnorderedList(out, env.getIgnoredNames().getItems());
out.append("</td></tr>");
printTableRow(out, "Index word limit", env.getIndexWordLimit());
printTableRow(out, "Allow leading wildcard in search",
env.isAllowLeadingWildcard());
printTableRow(out, "History cache", HistoryGuru.getInstance()
.getCacheInfo());
out.append("</table>");
}
/**
* Just read the given source and dump as is to the given destionation.
* Does nothing, if one or more of the parameters is {@code null}.
* @param out write destination
* @param in source to read
* @throws IOException as defined by the given reader/writer
* @throws NullPointerException if a parameter is {@code null}.
*/
public static final void dump(Writer out, Reader in) throws IOException {
if (in == null || out == null) {
return;
}
char[] buf = new char[8192];
int len = 0;
while ((len = in.read(buf)) >= 0) {
out.write(buf, 0, len);
}
}
/**
* Silently dump a file to the given destionation. All {@link IOException}s
* gets caught and logged, but not re-thrown.
*
* @param out dump destination
* @param dir directory, which should contains the file.
* @param filename the basename of the file to dump.
* @param compressed if {@code true} the denoted file is assumed to be
* gzipped.
* @return {@code true} on success (everything read and written).
* @throws NullPointerException if a parameter is {@code null}.
*/
public static boolean dump(Writer out, File dir, String filename,
boolean compressed)
{
return dump(out, new File(dir, filename), compressed);
}
/**
* Silently dump a file to the given destionation. All {@link IOException}s
* gets caught and logged, but not re-thrown.
*
* @param out dump destination
* @param file file to dump.
* @param compressed if {@code true} the denoted file is assumed to be
* gzipped.
* @return {@code true} on success (everything read and written).
* @throws NullPointerException if a parameter is {@code null}.
*/
public static boolean dump(Writer out, File file, boolean compressed) {
if (!file.exists()) {
return false;
}
FileInputStream fis = null;
GZIPInputStream gis = null;
Reader in = null;
try {
if (compressed) {
fis = new FileInputStream(file);
gis = new GZIPInputStream(fis);
in = new InputStreamReader(gis);
} else {
in = new FileReader(file);
}
dump(out, in);
return true;
} catch(IOException e) {
OpenGrokLogger.getLogger().log(Level.WARNING,
"An error occured while piping file " + file + ": ", e);
} finally {
if (in != null) {
try { in.close(); gis = null; fis = null; }
catch (Exception e) { /**/ }
}
if (gis != null) {
try { gis.close(); fis = null; }
catch (Exception e) { /**/ }
}
if (fis != null) {
try { fis.close();}
catch (Exception e) { /**/ }
}
}
return false;
}
/**
* Print a row in an HTML table.
*
* @param out
* destination for the HTML output
* @param cells
* the values to print in the cells of the row
* @throws IOException
* if an error happens while writing to {@code out}
*/
private static void printTableRow(Appendable out, Object... cells)
throws IOException
{
out.append("<tr>");
StringBuilder buf = new StringBuilder(256);
for (Object cell : cells) {
out.append("<td>");
String str = (cell == null) ? "null" : cell.toString();
htmlize(str, buf);
out.append(str);
buf.setLength(0);
out.append("</td>");
}
out.append("</tr>");
}
/**
* Print an unordered list (HTML).
*
* @param out
* destination for the HTML output
* @param items
* the list items
* @throws IOException
* if an error happens while writing to {@code out}
*/
private static void printUnorderedList(Appendable out,
Collection<String> items) throws IOException
{
out.append("<ul>");
StringBuilder buf = new StringBuilder(256);
for (String item : items) {
out.append("<li>");
htmlize(item, buf);
out.append(buf);
buf.setLength(0);
out.append("</li>");
}
out.append("</ul>");
}
/**
* Create a string literal for use in JavaScript functions.
*
* @param str
* the string to be represented by the literal
* @return a JavaScript string literal
*/
public static String jsStringLiteral(String str) {
StringBuilder sb = new StringBuilder();
sb.append('"');
for (int i = 0; i < str.length(); i++ ) {
char c = str.charAt(i);
switch (c) {
case '"':
sb.append("\\\"");
break;
case '\\':
sb.append("\\\\");
break;
case '\n':
sb.append("\\n");
break;
case '\r':
sb.append("\\r");
break;
default:
sb.append(c);
}
}
sb.append('"');
return sb.toString();
}
}