Issue #3708 - use StringUtil alternatives for known slow JVM impls.

+ StringUtil.replace()
+ StringUtil.replaceFirst()
+ StringUtil.sanitizeFileSystemPath()

Change existing usages of String.replace() to either
use new StringUtil.replace() or other methods elsewhere
that better suit that specific need.

Signed-off-by: Joakim Erdfelt <joakim.erdfelt@gmail.com>

jetty-ant/src/main/java/org/eclipse/jetty/ant/AntWebInfConfiguration.java

@@ -28,6 +28,7 @@ import java.util.regex.Pattern;
 
 import org.apache.tools.ant.AntClassLoader;
 import org.eclipse.jetty.util.PatternMatcher;
+import org.eclipse.jetty.util.URIUtil;
 import org.eclipse.jetty.util.resource.Resource;
 import org.eclipse.jetty.webapp.WebAppClassLoader;
 import org.eclipse.jetty.webapp.WebAppContext;
@@ -88,7 +89,7 @@ public class AntWebInfConfiguration extends WebInfConfiguration
                             }
                             catch (URISyntaxException e)
                             {
-                                containerUris[i] = new URI(u.toString().replaceAll(" ", "%20"));
+                                containerUris[i] = new URI(URIUtil.encodeSpaces(u.toString()));
                             }  
                             i++;
                         }

jetty-fcgi/fcgi-client/src/main/java/org/eclipse/jetty/fcgi/client/http/HttpSenderOverFCGI.java

@@ -88,7 +88,7 @@ public class HttpSenderOverFCGI extends HttpSender
         for (HttpField field : headers)
         {
             String name = field.getName();
-            String fcgiName = "HTTP_" + name.replaceAll("-", "_").toUpperCase(Locale.ENGLISH);
+            String fcgiName = "HTTP_" + name.replace('-', '_').toUpperCase(Locale.ENGLISH);
             fcgiHeaders.add(fcgiName, field.getValue());
         }
 

jetty-fcgi/fcgi-server/src/main/java/org/eclipse/jetty/fcgi/server/proxy/TryFilesFilter.java

@@ -24,7 +24,6 @@ import java.net.URL;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.Paths;
-
 import javax.servlet.Filter;
 import javax.servlet.FilterChain;
 import javax.servlet.FilterConfig;
@@ -35,6 +34,8 @@ import javax.servlet.ServletResponse;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
+import org.eclipse.jetty.util.StringUtil;
+
 /**
  * Inspired by nginx's try_files functionality.
  * <p>
@@ -132,7 +133,7 @@ public class TryFilesFilter implements Filter
             path += info;
         if (!path.startsWith("/"))
             path = "/" + path;
-        return value.replaceAll("\\$path", path);
+        return StringUtil.replace(value, "$path", path);
     }
 
     @Override

jetty-http/src/main/java/org/eclipse/jetty/http/MimeTypes.java

@@ -196,7 +196,7 @@ public class MimeTypes
             int charset=type.toString().indexOf(";charset=");
             if (charset>0)
             {
-                String alt=type.toString().replace(";charset=","; charset=");
+                String alt = StringUtil.replace(type.toString(), ";charset=", "; charset=");
                 CACHE.put(alt,type);
                 TYPES.put(alt,type.asBuffer());
             }

jetty-jmh/src/main/java/org/eclipse/jetty/util/StringReplaceBenchmark.java

@@ -0,0 +1,119 @@
+//
+//  ========================================================================
+//  Copyright (c) 1995-2019 Mort Bay Consulting Pty. Ltd.
+//  ------------------------------------------------------------------------
+//  All rights reserved. This program and the accompanying materials
+//  are made available under the terms of the Eclipse Public License v1.0
+//  and Apache License v2.0 which accompanies this distribution.
+//
+//      The Eclipse Public License is available at
+//      http://www.eclipse.org/legal/epl-v10.html
+//
+//      The Apache License v2.0 is available at
+//      http://www.opensource.org/licenses/apache2.0.php
+//
+//  You may elect to redistribute this code under either of these licenses.
+//  ========================================================================
+//
+
+package org.eclipse.jetty.util;
+
+import java.util.concurrent.TimeUnit;
+
+import org.openjdk.jmh.annotations.Benchmark;
+import org.openjdk.jmh.annotations.Fork;
+import org.openjdk.jmh.annotations.Level;
+import org.openjdk.jmh.annotations.Measurement;
+import org.openjdk.jmh.annotations.Param;
+import org.openjdk.jmh.annotations.Scope;
+import org.openjdk.jmh.annotations.Setup;
+import org.openjdk.jmh.annotations.State;
+import org.openjdk.jmh.annotations.Warmup;
+import org.openjdk.jmh.infra.Blackhole;
+import org.openjdk.jmh.runner.Runner;
+import org.openjdk.jmh.runner.RunnerException;
+import org.openjdk.jmh.runner.options.Options;
+import org.openjdk.jmh.runner.options.OptionsBuilder;
+
+@Fork(value = 3)
+@State(Scope.Benchmark)
+@Warmup(iterations = 4, time = 1, timeUnit = TimeUnit.SECONDS)
+@Measurement(iterations = 4, time = 1, timeUnit = TimeUnit.SECONDS)
+public class StringReplaceBenchmark
+{
+    @Param({"3", "100", "1000"})
+    int size;
+
+    @Param({"0", "1", "3", "50"})
+    int matches;
+
+    String input;
+
+    @Setup(Level.Trial)
+    public void setupTrial() throws Exception
+    {
+        String pattern = "abc";
+        StringBuilder str = new StringBuilder();
+        while (str.length() < size)
+        {
+            str.append(pattern);
+        }
+
+        if (matches > 0)
+        {
+            int partSize = (int)((double)str.length() / (double)matches);
+            for (int i = 0; i < matches; i++)
+            {
+                str.insert((i * partSize), "'");
+            }
+        }
+        input = str.toString();
+    }
+
+    @Benchmark
+    public void testJavaStringReplace_Growth(Blackhole blackhole)
+    {
+        blackhole.consume(input.replace("'", "FOOBAR"));
+    }
+
+    @Benchmark
+    public void testJavaStringReplace_Same(Blackhole blackhole)
+    {
+        blackhole.consume(input.replace("'", "X"));
+    }
+
+    @Benchmark
+    public void testJavaStringReplace_Reduce(Blackhole blackhole)
+    {
+        blackhole.consume(input.replace("'", ""));
+    }
+
+    @Benchmark
+    public void testJettyStringUtilReplace_Growth(Blackhole blackhole)
+    {
+        blackhole.consume(StringUtil.replace(input, "'", "FOOBAR"));
+    }
+
+    @Benchmark
+    public void testJettyStringUtilReplace_Same(Blackhole blackhole)
+    {
+        blackhole.consume(StringUtil.replace(input, "'", "X"));
+    }
+
+    @Benchmark
+    public void testJettyStringUtilReplace_Reduce(Blackhole blackhole)
+    {
+        blackhole.consume(StringUtil.replace(input, "'", ""));
+    }
+
+    public static void main(String[] args) throws RunnerException
+    {
+        Options opt = new OptionsBuilder()
+            .include(StringReplaceBenchmark.class.getSimpleName())
+//            .addProfiler(GCProfiler.class)
+            .forks(1)
+            .build();
+
+        new Runner(opt).run();
+    }
+}

jetty-nosql/src/main/java/org/eclipse/jetty/nosql/mongodb/MongoUtils.java

@@ -27,10 +27,10 @@ import java.util.Date;
 import java.util.HashMap;
 import java.util.Map;
 
-import org.eclipse.jetty.util.ClassLoadingObjectInputStream;
-
 import com.mongodb.BasicDBObject;
 import com.mongodb.DBObject;
+import org.eclipse.jetty.util.ClassLoadingObjectInputStream;
+import org.eclipse.jetty.util.StringUtil;
 
 /**
  * MongoUtils
@@ -69,23 +69,23 @@ public class MongoUtils
             throw new IllegalStateException(valueToDecode.getClass().toString());
         }
     }
-   
+
-    
-    
     public static String decodeName(String name)
     {
-        return name.replace("%2E",".").replace("%25","%");
+        String cleaned = name;
+        cleaned = StringUtil.replace(cleaned, "%2E", ".");
+        cleaned = StringUtil.replace(cleaned, "%25", "%");
+        return cleaned;
     }
-    
 
-    
     public static String encodeName(String name)
     {
-        return name.replace("%","%25").replace(".","%2E");
+        String cleaned = name;
+        cleaned = StringUtil.replace(cleaned, "%", "%25");
+        cleaned = StringUtil.replace(cleaned, ".", "%2E");
+        return cleaned;
     }
 
-
-    
     public static Object encodeName(Object value) throws IOException
     {
         if (value instanceof Number || value instanceof String || value instanceof Boolean || value instanceof Date)

jetty-osgi/jetty-osgi-boot/src/main/java/org/eclipse/jetty/osgi/boot/OSGiWebInfConfiguration.java

@@ -35,6 +35,7 @@ import java.util.regex.Pattern;
 import org.eclipse.jetty.osgi.boot.utils.BundleFileLocatorHelperFactory;
 import org.eclipse.jetty.osgi.boot.utils.Util;
 import org.eclipse.jetty.osgi.boot.utils.internal.PackageAdminServiceTracker;
+import org.eclipse.jetty.util.URIUtil;
 import org.eclipse.jetty.util.log.Log;
 import org.eclipse.jetty.util.log.Logger;
 import org.eclipse.jetty.util.resource.Resource;
@@ -339,7 +340,7 @@ public class OSGiWebInfConfiguration extends WebInfConfiguration
         }
         catch (URISyntaxException e)
         {
-            uri = new URI(url.toString().replaceAll(" ", "%20"));
+            uri = new URI(URIUtil.encodeSpaces(url.toString()));
         }
         String key = resourcePath.startsWith("/") ? resourcePath.substring(1) : resourcePath;
         resourceMap.put(key + ";" + fragment.getSymbolicName(), Resource.newResource(uri));

jetty-proxy/src/test/java/org/eclipse/jetty/proxy/ProxyServletTest.java

@@ -43,7 +43,6 @@ import java.util.concurrent.ExecutionException;
 import java.util.concurrent.TimeUnit;
 import java.util.stream.Stream;
 import java.util.zip.GZIPOutputStream;
-
 import javax.servlet.AsyncContext;
 import javax.servlet.AsyncEvent;
 import javax.servlet.AsyncListener;
@@ -670,7 +669,7 @@ public class ProxyServletTest
 
         // Make the request to the proxy, it should transparently forward to the server
         ContentResponse response = client.newRequest("localhost", proxyConnector.getLocalPort())
-                .path((prefix + target).replaceAll("//", "/"))
+                .path((prefix + target).replace("//", "/"))
                 .timeout(5, TimeUnit.SECONDS)
                 .send();
         assertEquals(200, response.getStatus());

jetty-quickstart/src/main/java/org/eclipse/jetty/quickstart/AttributeNormalizer.java

@@ -37,6 +37,7 @@ import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 import java.util.stream.Stream;
 
+import org.eclipse.jetty.util.StringUtil;
 import org.eclipse.jetty.util.log.Log;
 import org.eclipse.jetty.util.log.Logger;
 import org.eclipse.jetty.util.resource.Resource;
@@ -454,13 +455,7 @@ public class AttributeNormalizer
         // leftover
         expanded.append(str.substring(offset));
 
-        // special case for "$$"
+        return StringUtil.replace(expanded.toString(), "$$", "$");
-        if (expanded.indexOf("$$") >= 0)
-        {
-            return expanded.toString().replaceAll("\\$\\$","\\$");
-        }
-
-        return expanded.toString();
     }
 
     private String getString(String property)

jetty-rewrite/src/main/java/org/eclipse/jetty/rewrite/handler/RedirectRegexRule.java

@@ -24,6 +24,7 @@ import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
 import org.eclipse.jetty.http.HttpStatus;
+import org.eclipse.jetty.util.StringUtil;
 import org.eclipse.jetty.util.annotation.Name;
 
 /**
@@ -93,7 +94,7 @@ public class RedirectRegexRule extends RegexRule
         for (int g = 1; g <= matcher.groupCount(); g++)
         {
             String group = matcher.group(g);
-            target = target.replaceAll("\\$" + g, group);
+            target = StringUtil.replace(target, "$" + g, group);
         }
 
         target = response.encodeRedirectURL(target);
@@ -110,6 +111,11 @@ public class RedirectRegexRule extends RegexRule
     @Override
     public String toString()
     {
-        return String.format("%s[%d>%s]", super.toString(), _statusCode, _location);
+        StringBuilder str = new StringBuilder();
+        str.append(super.toString());
+        str.append('[').append(_statusCode);
+        str.append('>').append(_location);
+        str.append(']');
+        return str.toString();
     }
 }

jetty-rewrite/src/main/java/org/eclipse/jetty/rewrite/handler/RewriteRegexRule.java

@@ -20,11 +20,11 @@ package org.eclipse.jetty.rewrite.handler;
 
 import java.io.IOException;
 import java.util.regex.Matcher;
-
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
 import org.eclipse.jetty.server.Request;
+import org.eclipse.jetty.util.StringUtil;
 import org.eclipse.jetty.util.annotation.Name;
 
 /**
@@ -96,15 +96,22 @@ public class RewriteRegexRule extends RegexRule  implements Rule.ApplyURI
                 group="";
             else
                 group = Matcher.quoteReplacement(group);
-            target=target.replaceAll("\\$"+g,group);
+            String dollarGroup = "$" + g;
-            if (query!=null)
+            target = StringUtil.replace(target, dollarGroup, group);
-                query=query.replaceAll("\\$"+g,group);
+            if (query != null)
+                query = StringUtil.replace(query, dollarGroup, group);
         }
 
         if (query!=null)
         {
             if (_queryGroup)
-                query=query.replace("$Q",request.getQueryString()==null?"":request.getQueryString());
+            {
+                String replacement = "";
+                if (request.getQueryString() != null)
+                    replacement = request.getQueryString();
+
+                query = StringUtil.replace(query, "$Q", replacement);
+            }
             request.setAttribute("org.eclipse.jetty.rewrite.handler.RewriteRegexRule.Q",query);
         }
         

jetty-security/src/main/java/org/eclipse/jetty/security/PropertyUserStore.java

@@ -140,7 +140,8 @@ public class PropertyUserStore extends UserStore implements PathWatcher.Listener
         int bang_slash = uri.indexOf("!/");
         if (colon < 0 || bang_slash < 0 || colon > bang_slash)
             throw new IllegalArgumentException("Not resolved JarFile resource: " + uri);
-        String entry_path = uri.substring(colon + 2).replace("!/", "__").replace('/', '_').replace('.', '_');
+
+        String entry_path = StringUtil.sanitizeFileSystemPath(uri.substring(colon + 2));
 
         Path tmpDirectory = Files.createTempDirectory("users_store");
         tmpDirectory.toFile().deleteOnExit();

jetty-server/src/main/java/org/eclipse/jetty/server/Response.java

@@ -52,12 +52,10 @@ import org.eclipse.jetty.http.HttpVersion;
 import org.eclipse.jetty.http.MetaData;
 import org.eclipse.jetty.http.MimeTypes;
 import org.eclipse.jetty.http.PreEncodedHttpField;
-import org.eclipse.jetty.http.Syntax;
 import org.eclipse.jetty.io.RuntimeIOException;
 import org.eclipse.jetty.server.handler.ContextHandler;
 import org.eclipse.jetty.server.handler.ErrorHandler;
 import org.eclipse.jetty.server.session.SessionHandler;
-import org.eclipse.jetty.util.QuotedStringTokenizer;
 import org.eclipse.jetty.util.StringUtil;
 import org.eclipse.jetty.util.URIUtil;
 import org.eclipse.jetty.util.log.Log;
@@ -237,7 +235,7 @@ public class Response implements HttpServletResponse
             if (i >= 0)
             {
                 httpOnly = true;
-                comment = comment.replace(HTTP_ONLY_COMMENT, "").trim();
+                comment = StringUtil.replace(comment.trim(), HTTP_ONLY_COMMENT, "");
                 if (comment.length() == 0)
                     comment = null;
             }

jetty-server/src/main/java/org/eclipse/jetty/server/handler/DefaultHandler.java

@@ -164,7 +164,7 @@ public class DefaultHandler extends AbstractHandler
                 {
                     writer.append("<a href=\"").append(href).append("\">");
                 }
-                writer.append(contextPath.replaceAll("%", "&#37;"));
+                writer.append(StringUtil.replace(contextPath, "%", "&#37;"));
                 if (context.isRunning())
                 {
                     writer.append("</a>");

jetty-servlet/src/test/java/org/eclipse/jetty/servlet/ResponseHeadersTest.java

@@ -18,13 +18,9 @@
 
 package org.eclipse.jetty.servlet;
 
-import static org.hamcrest.MatcherAssert.assertThat;
-import static org.hamcrest.Matchers.is;
-
 import java.io.IOException;
 import java.net.URLDecoder;
 import java.nio.ByteBuffer;
-
 import javax.servlet.ServletException;
 import javax.servlet.http.HttpServlet;
 import javax.servlet.http.HttpServletRequest;
@@ -38,6 +34,9 @@ import org.junit.jupiter.api.AfterAll;
 import org.junit.jupiter.api.BeforeAll;
 import org.junit.jupiter.api.Test;
 
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.is;
+
 public class ResponseHeadersTest
 {
     public static class SimulateUpgradeServlet extends HttpServlet
@@ -144,7 +143,7 @@ public class ResponseHeadersTest
         assertThat("Response Code",response.getStatus(),is(200));
         assertThat("Response Header Content-Type",response.get("Content-Type"),is("text/plain;charset=UTF-8"));
 
-        String expected = actualPathInfo.replaceAll("%0A", " "); // replace OBS fold with space
+        String expected = actualPathInfo.replace("%0A", " "); // replace OBS fold with space
         expected = URLDecoder.decode(expected, "utf-8"); // decode the rest
         expected = expected.trim(); // trim whitespace at start/end
         assertThat("Response Header X-example", response.get("X-Example"), is(expected));

jetty-servlets/src/main/java/org/eclipse/jetty/servlets/CrossOriginFilter.java

@@ -26,7 +26,6 @@ import java.util.Enumeration;
 import java.util.List;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
-
 import javax.servlet.Filter;
 import javax.servlet.FilterChain;
 import javax.servlet.FilterConfig;
@@ -368,8 +367,8 @@ public class CrossOriginFilter implements Filter
 
     private String parseAllowedWildcardOriginToRegex(String allowedOrigin)
     {
-        String regex = allowedOrigin.replace(".", "\\.");
+        String regex = StringUtil.replace(allowedOrigin, ".", "\\.");
-        return regex.replace("*", ".*"); // we want to be greedy here to match multiple subdomains, thus we use .*
+        return StringUtil.replace(regex, "*", ".*"); // we want to be greedy here to match multiple subdomains, thus we use .*
     }
 
     private boolean isSimpleRequest(HttpServletRequest request)

jetty-util/src/main/java/org/eclipse/jetty/util/StringUtil.java

@@ -26,14 +26,13 @@ import java.util.List;
 import org.eclipse.jetty.util.log.Log;
 import org.eclipse.jetty.util.log.Logger;
 
-/** Fast String Utilities.
+/**
+ * Fast String Utilities.
  *
  * These string utilities provide both convenience methods and
  * performance improvements over most standard library versions. The
  * main aim of the optimizations is to avoid object creation unless
  * absolutely required.
- *
- * 
  */
 public class StringUtil
 {
@@ -62,8 +61,7 @@ public class StringUtil
         CHARSETS.put("iso-8859-1",__ISO_8859_1);
         CHARSETS.put("iso_8859_1",__ISO_8859_1);
     }
-    
+
-    /* ------------------------------------------------------------ */
     /** Convert alternate charset names (eg utf8) to normalized
      * name (eg UTF-8).
      * @param s the charset to normalize
@@ -74,8 +72,7 @@ public class StringUtil
         String n=CHARSETS.get(s);
         return (n==null)?s:n;
     }
-    
+
-    /* ------------------------------------------------------------ */
     /** Convert alternate charset names (eg utf8) to normalized
      * name (eg UTF-8).
      * @param s the charset to normalize
@@ -88,9 +85,7 @@ public class StringUtil
         String n=CHARSETS.get(s,offset,length);       
         return (n==null)?s.substring(offset,offset+length):n;
     }
-    
 
-    /* ------------------------------------------------------------ */
     public static final char[] lowercases = {
           '\000','\001','\002','\003','\004','\005','\006','\007',
           '\010','\011','\012','\013','\014','\015','\016','\017',
@@ -109,7 +104,6 @@ public class StringUtil
           '\160','\161','\162','\163','\164','\165','\166','\167',
           '\170','\171','\172','\173','\174','\175','\176','\177' };
 
-    /* ------------------------------------------------------------ */
     /**
      * fast lower case conversion. Only works on ascii (not unicode)
      * @param s the string to convert
@@ -122,7 +116,6 @@ public class StringUtil
         
         char[] c = null;
         int i=s.length();
-
         // look for first conversion
         while (i-->0)
         {
@@ -138,7 +131,6 @@ public class StringUtil
                 }
             }
         }
-
         while (i-->0)
         {
             if(c[i]<=127)
@@ -148,8 +140,43 @@ public class StringUtil
         return c==null?s:new String(c);
     }
 
+    /**
+     * Replace all characters from input string that are known to have
+     * special meaning in various filesytems.
+     *
+     * <p>
+     *     This will replace all of the following characters
+     *     with a "{@code _}" (underscore).
+     * </p>
+     * <ul>
+     *     <li>Control Characters</li>
+     *     <li>Anything not 7-bit printable ASCII</li>
+     *     <li>Special characters "{@code !|/.,:&><\?*"}"</li>
+     * </ul>
+     *
+     * @param str the raw input string
+     * @return the sanitized output string.
+     */
+    public static String sanitizeFileSystemPath(String str)
+    {
+        char[] chars = str.toCharArray();
+        int len = chars.length;
+        for (int i = 0; i < len; i++)
+        {
+            char c = chars[i];
+            if ((c <= 0x1F) || // control characters
+                (c >= 0x7F) || // over 7-bit printable ASCII
+                (c == '!') || (c == '|') || (c == '.') ||
+                (c == ':') || (c == '>') || (c == '<') ||
+                (c == '?') || (c == '/') || (c == '\\') ||
+                (c == '*') || (c == '"') || (c == '&'))
+            {
+                chars[i] = '_';
+            }
+        }
+        return String.valueOf(chars);
+    }
 
-    /* ------------------------------------------------------------ */
     public static boolean startsWithIgnoreCase(String s,String w)
     {
         if (w==null)
@@ -174,13 +201,11 @@ public class StringUtil
         }
         return true;
     }
-    
+
-    /* ------------------------------------------------------------ */
     public static boolean endsWithIgnoreCase(String s,String w)
     {
         if (w==null)
             return true;
-
         if (s==null)
             return false;
             
@@ -206,8 +231,7 @@ public class StringUtil
         }
         return true;
     }
-    
+
-    /* ------------------------------------------------------------ */
     /**
      * returns the next index of a character from the chars string
      * @param s the input string to search
@@ -221,10 +245,13 @@ public class StringUtil
               return i;
         return -1;
     }
-    
+
-    /* ------------------------------------------------------------ */
     /**
-     * replace substrings within string.
+     * Replace substrings within string.
+     * <p>
+     *     Fast replacement for {@code java.lang.String#}{@link String#replace(CharSequence, CharSequence)}
+     * </p>
+     *
      * @param s the input string
      * @param sub the string to look for
      * @param with the string to replace with
@@ -232,27 +259,56 @@ public class StringUtil
      */
     public static String replace(String s, String sub, String with)
     {
-        int c=0;
+        int c = 0;
-        int i=s.indexOf(sub,c);
+        int i = s.indexOf(sub, c);
         if (i == -1)
+        {
             return s;
-    
+        }
-        StringBuilder buf = new StringBuilder(s.length()+with.length());
+        StringBuilder buf = new StringBuilder(s.length() + with.length());
-
         do
         {
-            buf.append(s.substring(c,i));
+            buf.append(s, c, i);
             buf.append(with);
-            c=i+sub.length();
+            c = i + sub.length();
-        } while ((i=s.indexOf(sub,c))!=-1);
+        }
-
+        while ((i = s.indexOf(sub, c)) != -1);
-        if (c<s.length())
+        if (c < s.length())
-            buf.append(s.substring(c,s.length()));
+        {
-
+            buf.append(s.substring(c));
+        }
         return buf.toString();   
     }
 
-    /* ------------------------------------------------------------ */
+    /**
+     * Replace first substrings within string.
+     * <p>
+     *     Fast replacement for {@code java.lang.String#}{@link String#replaceFirst(String, String)}, but without
+     *     Regex support.
+     * </p>
+     *
+     * @param original the original string
+     * @param target the target string to look for
+     * @param replacement the replacement string to use
+     * @return the replaced string
+     */
+    public static String replaceFirst(String original, String target, String replacement)
+    {
+        int idx = original.indexOf(target);
+        if (idx == -1)
+            return original;
+
+        int offset = 0;
+        int originalLen = original.length();
+        StringBuilder buf = new StringBuilder(originalLen + replacement.length());
+        buf.append(original, offset, idx);
+        offset += idx + target.length();
+        buf.append(replacement);
+        buf.append(original, offset, originalLen);
+
+        return buf.toString();
+    }
+
     /** Remove single or double quotes.
      * @param s the input string
      * @return the string with quotes removed
@@ -263,8 +319,6 @@ public class StringUtil
         return QuotedStringTokenizer.unquote(s);
     }
 
-
-    /* ------------------------------------------------------------ */
     /** Append substring to StringBuilder 
      * @param buf StringBuilder to append to
      * @param s String to append from
@@ -288,8 +342,6 @@ public class StringUtil
         }
     }
 
-    
-    /* ------------------------------------------------------------ */
     /**
      * append hex digit
      * @param buf the buffer to append to
@@ -310,7 +362,6 @@ public class StringUtil
         buf.append((char)c);
     }
 
-    /* ------------------------------------------------------------ */
     /**
      * Append 2 digits (zero padded) to the StringBuffer
      * 
@@ -325,8 +376,7 @@ public class StringUtil
             buf.append((char)(i%10+'0'));
         }
     }
-    
+
-    /* ------------------------------------------------------------ */
     /**
      * Append 2 digits (zero padded) to the StringBuilder
      * 
@@ -341,8 +391,7 @@ public class StringUtil
             buf.append((char)(i%10+'0'));
         }
     }
-    
+
-    /* ------------------------------------------------------------ */
     /** Return a non null string.
      * @param s String
      * @return The string passed in or empty string if it is null. 
@@ -353,8 +402,7 @@ public class StringUtil
             return "";
         return s;
     }
-    
+
-    /* ------------------------------------------------------------ */
     public static boolean equals(String s,char[] buf, int offset, int length)
     {
         if (s.length()!=length)
@@ -365,13 +413,11 @@ public class StringUtil
         return true;
     }
 
-    /* ------------------------------------------------------------ */
     public static String toUTF8String(byte[] b,int offset,int length)
     {
         return new String(b,offset,length,StandardCharsets.UTF_8);
     }
 
-    /* ------------------------------------------------------------ */
     public static String toString(byte[] b,int offset,int length,String charset)
     {
         try
@@ -380,6 +426,7 @@ public class StringUtil
         }
         catch (UnsupportedEncodingException e)
         {
+            LOG.warn(e);
             throw new IllegalArgumentException(e);
         }
     }
@@ -431,7 +478,6 @@ public class StringUtil
         return -1;
     }
 
-    /* ------------------------------------------------------------ */
     /**
      * Test if a string is null or only has whitespace characters in it.
      * <p>
@@ -494,7 +540,6 @@ public class StringUtil
         return str == null || str.isEmpty();
     }
 
-    /* ------------------------------------------------------------ */
     /**
      * Test if a string is not null and contains at least 1 non-whitespace characters in it.
      * <p>
@@ -534,14 +579,11 @@ public class StringUtil
         return false;
     }
 
-    /* ------------------------------------------------------------ */
     public static boolean isUTF8(String charset)
     {
         return __UTF8.equalsIgnoreCase(charset)||__UTF8.equalsIgnoreCase(normalizeCharset(charset));
     }
 
-
-    /* ------------------------------------------------------------ */
     public static String printable(String name)
     {
         if (name==null)
@@ -556,7 +598,7 @@ public class StringUtil
         return buf.toString();
     }
     
-    /* ------------------------------------------------------------ */
+
     public static String printable(byte[] b)
     {
         StringBuilder buf = new StringBuilder();
@@ -592,13 +634,10 @@ public class StringUtil
         }
         catch(Exception e)
         {
-            LOG.warn(e);
             return s.getBytes();
         }
     }
-    
+
-    
-    
     /**
      * Converts a binary SID to a string SID
      * 
@@ -631,7 +670,6 @@ public class StringUtil
    
         // the number of subAuthorities we need to attach
         int subAuthorityCount = sidBytes[1];
-
         // attach each of the subAuthorities
         for (int i = 0; i < subAuthorityCount; ++i)
         {
@@ -670,10 +708,8 @@ public class StringUtil
         
         // the revision byte
         sidBytes[byteCount++] = (byte)Integer.parseInt(sidTokens[1]);
-
         // the # of sub authorities byte
         sidBytes[byteCount++] = (byte)subAuthorityCount;
-
         // the certAuthority
         String hexStr = Long.toHexString(Long.parseLong(sidTokens[2]));
         
@@ -681,7 +717,6 @@ public class StringUtil
         {
             hexStr = "0" + hexStr;
         }
-
         // place the certAuthority 6 bytes
         for ( int i = 0 ; i < hexStr.length(); i = i + 2)
         {
@@ -720,7 +755,6 @@ public class StringUtil
         int val = 0;
         boolean started = false;
         boolean minus = false;
-
         for (int i = from; i < string.length(); i++)
         {
             char b = string.charAt(i);
@@ -741,7 +775,6 @@ public class StringUtil
             else
                 break;
         }
-
         if (started)
             return minus?(-val):val;
         throw new NumberFormatException(string);
@@ -759,7 +792,6 @@ public class StringUtil
         long val = 0;
         boolean started = false;
         boolean minus = false;
-
         for (int i = 0; i < string.length(); i++)
         {
             char b = string.charAt(i);
@@ -780,7 +812,6 @@ public class StringUtil
             else
                 break;
         }
-
         if (started)
             return minus?(-val):val;
         throw new NumberFormatException(string);
@@ -799,12 +830,10 @@ public class StringUtil
         {
             return null;
         }
-
         if (str.length() <= maxSize)
         {
             return str;
         }
-
         return str.substring(0,maxSize);
     }
 
@@ -817,20 +846,18 @@ public class StringUtil
     {
         if (s==null)
             return new String[]{};
-
         if (!s.startsWith("[") || !s.endsWith("]"))
             throw new IllegalArgumentException();
         if (s.length()==2)
             return new String[]{};
-
         return csvSplit(s,1,s.length()-2);
     }
     
     /**
-    * Parse a CSV string using {@link #csvSplit(List,String, int, int)}
+     * Parse a CSV string using {@link #csvSplit(List,String, int, int)}
-    * @param s The string to parse
+     * @param s The string to parse
-    * @return An array of parsed values.
+     * @return An array of parsed values.
-    */
+     */
     public static String[] csvSplit(String s)
     {
         if (s==null)
@@ -851,13 +878,12 @@ public class StringUtil
             return null;
         if (off<0 || len<0 || off>s.length())
             throw new IllegalArgumentException();
-
         List<String> list = new ArrayList<>();
         csvSplit(list,s,off,len);
         return list.toArray(new String[list.size()]);
     }
 
-    enum CsvSplitState { PRE_DATA, QUOTE, SLOSH, DATA, WHITE, POST_DATA };
+    enum CsvSplitState { PRE_DATA, QUOTE, SLOSH, DATA, WHITE, POST_DATA }
 
     /** Split a quoted comma separated string to a list
      * <p>Handle <a href="https://www.ietf.org/rfc/rfc4180.txt">rfc4180</a>-like 
@@ -890,7 +916,6 @@ public class StringUtil
                 case PRE_DATA:
                     if (Character.isWhitespace(ch))
                         continue;
-
                     if ('"'==ch)
                     {
                         state=CsvSplitState.QUOTE;
@@ -902,11 +927,9 @@ public class StringUtil
                         list.add("");
                         continue;
                     }
-
                     state=CsvSplitState.DATA;
                     out.append(ch);
                     continue;
-
                 case DATA:
                     if (Character.isWhitespace(ch))
                     {
@@ -923,7 +946,6 @@ public class StringUtil
                         state=CsvSplitState.PRE_DATA;
                         continue;
                     }
-
                     out.append(ch);
                     continue;
                     
@@ -947,7 +969,6 @@ public class StringUtil
                     out.append(ch);
                     last=-1;
                     continue;
-
                 case QUOTE:
                     if ('\\'==ch)
                     {
@@ -978,13 +999,11 @@ public class StringUtil
                     continue;
             }
         }
-
         switch(state)
         {
             case PRE_DATA:
             case POST_DATA:
                 break;
-
             case DATA:
             case QUOTE:
             case SLOSH:
@@ -1011,7 +1030,6 @@ public class StringUtil
         loop: for (;i<html.length();i++)
         {
             char c=html.charAt(i);
-
             switch(c)
             {
                 case '&' :
@@ -1020,13 +1038,11 @@ public class StringUtil
                 case '\'':
                 case '"':
                     break loop;
-
                 default:
                     if (Character.isISOControl(c) && !Character.isWhitespace(c))
                         break loop;
             }
         }
-
         // No characters need sanitizing, so return original string
         if (i==html.length())
             return html;
@@ -1039,7 +1055,6 @@ public class StringUtil
         for (;i<html.length();i++)
         {
             char c=html.charAt(i);
-
             switch(c)
             {
                 case '&' :
@@ -1057,7 +1072,6 @@ public class StringUtil
                 case '"':
                     out.append("&quot;");
                     break;
-
                 default:
                     if (Character.isISOControl(c) && !Character.isWhitespace(c))
                         out.append('?');
@@ -1067,8 +1081,7 @@ public class StringUtil
         }
         return out.toString();
     }
-    
+
-    /* ------------------------------------------------------------ */
     /** The String value of an Object
      * <p>This method calls {@link String#valueOf(Object)} unless the object is null,
      * in which case null is returned</p>

jetty-util/src/main/java/org/eclipse/jetty/util/URIUtil.java

@@ -268,7 +268,19 @@ public class URIUtil
 
         return buf;
     }
-    
+
+    /**
+     * Encode a raw URI String and convert any raw spaces to
+     * their "%20" equivalent.
+     *
+     * @param str input raw string
+     * @return output with spaces converted to "%20"
+     */
+    public static String encodeSpaces(String str)
+    {
+        return StringUtil.replace(str, " ", "%20");
+    }
+
     /* ------------------------------------------------------------ */
     /** Encode a URI path.
      * @param path The path the encode

jetty-util/src/main/java/org/eclipse/jetty/util/component/Dumpable.java

@@ -26,6 +26,7 @@ import java.util.Iterator;
 import java.util.Map;
 import java.util.stream.Stream;
 
+import org.eclipse.jetty.util.StringUtil;
 import org.eclipse.jetty.util.annotation.ManagedObject;
 import org.eclipse.jetty.util.annotation.ManagedOperation;
 
@@ -99,9 +100,15 @@ public interface Dumpable
             else if (o instanceof Map)
                 s = String.format("%s@%x{size=%d}",o.getClass().getName(),o.hashCode(),((Map<?,?>)o).size());
             else if (o instanceof Dumpable)
-                s = ((Dumpable)o).dumpSelf().replace("\r\n","|").replace("\n","|");
+            {
+                s = StringUtil.replace(((Dumpable)o).dumpSelf(), "\r\n", "|")
+                    .replace('\n', '|');
+            }
             else
-                s = String.valueOf(o).replace("\r\n","|").replace("\n","|");
+            {
+                s = StringUtil.replace(String.valueOf(o), "\r\n", "|")
+                    .replace('\n', '|');
+            }
 
             if (o instanceof LifeCycle)
                 out.append(s).append(" - ").append((AbstractLifeCycle.getState((LifeCycle)o))).append("\n");

jetty-util/src/test/java/org/eclipse/jetty/util/StringUtilTest.java

@@ -18,19 +18,21 @@
 
 package org.eclipse.jetty.util;
 
-import java.nio.charset.StandardCharsets;
+import java.util.ArrayList;
-import java.util.concurrent.TimeUnit;
+import java.util.List;
-
+import java.util.stream.Stream;
 
 import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.MethodSource;
 
+import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.arrayContaining;
 import static org.hamcrest.Matchers.emptyArray;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.nullValue;
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertFalse;
-import static org.hamcrest.MatcherAssert.assertThat;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 
 public class StringUtilTest
@@ -98,7 +100,36 @@ public class StringUtilTest
 
         s=" \u0690bc ";
         assertEquals(StringUtil.replace(s, "\u0690bc", "xyz")," xyz ");
+    }
 
+    public static Stream<String[]> replaceFirstArgs() {
+        List<String[]> data = new ArrayList<>();
+
+        // [original, target, replacement, expected]
+
+        // no match
+        data.add(new String[]{ "abc", "z", "foo", "abc" });
+
+        // matches at start of string
+        data.add(new String[]{ "abc", "a", "foo", "foobc" });
+        data.add(new String[]{ "abcabcabc", "a", "foo", "foobcabcabc" });
+
+        // matches in middle of string
+        data.add(new String[]{ "abc", "b", "foo", "afooc" });
+        data.add(new String[]{ "abcabcabc", "b", "foo", "afoocabcabc" });
+        data.add(new String[]{ "abcabcabc", "cab", "X", "abXcabc" });
+
+        // matches at end of string
+        data.add(new String[]{ "abc", "c", "foo", "abfoo" });
+
+        return data.stream();
+    }
+
+    @ParameterizedTest
+    @MethodSource(value = "replaceFirstArgs")
+    public void testReplaceFirst(String original, String target, String replacement, String expected)
+    {
+        assertThat(StringUtil.replaceFirst(original, target, replacement), is(expected));
     }
 
     @Test
@@ -165,50 +196,6 @@ public class StringUtilTest
         assertEquals(sid5, StringUtil.sidBytesToString(sid5Bytes));
         assertEquals(sid6, StringUtil.sidBytesToString(sid6Bytes));
         assertEquals(sid12, StringUtil.sidBytesToString(sid12Bytes));
-
-    }
-
-
-    public static void main(String[] arg) throws Exception
-    {
-        String string = "Now \u0690xxxxxxxx";
-        System.err.println(string);
-        byte[] bytes=string.getBytes(StandardCharsets.UTF_8);
-        System.err.println(new String(bytes));
-        System.err.println(bytes.length);
-        long calc=0;
-        Utf8StringBuffer strbuf = new Utf8StringBuffer(bytes.length);
-        for (int i=0;i<10;i++)
-        {
-            long s1=TimeUnit.NANOSECONDS.toMillis(System.nanoTime());
-            for (int j=1000000; j-->0;)
-            {
-                calc+=new String(bytes,0,bytes.length,StandardCharsets.UTF_8).hashCode();
-            }
-            long s2=TimeUnit.NANOSECONDS.toMillis(System.nanoTime());
-            for (int j=1000000; j-->0;)
-            {
-                calc+=StringUtil.toUTF8String(bytes,0,bytes.length).hashCode();
-            }
-            long s3=TimeUnit.NANOSECONDS.toMillis(System.nanoTime());
-            for (int j=1000000; j-->0;)
-            {
-                Utf8StringBuffer buffer = new Utf8StringBuffer(bytes.length);
-                buffer.append(bytes,0,bytes.length);
-                calc+=buffer.toString().hashCode();
-            }
-            long s4=TimeUnit.NANOSECONDS.toMillis(System.nanoTime());
-            for (int j=1000000; j-->0;)
-            {
-                strbuf.reset();
-                strbuf.append(bytes,0,bytes.length);
-                calc+=strbuf.toString().hashCode();
-            }
-            long s5=TimeUnit.NANOSECONDS.toMillis(System.nanoTime());
-
-            System.err.println((s2-s1)+", "+(s3-s2)+", "+(s4-s3)+", "+(s5-s4));
-        }
-        System.err.println(calc);
     }
 
     @Test

jetty-webapp/src/main/java/org/eclipse/jetty/webapp/ClasspathPattern.java

@@ -703,7 +703,7 @@ public class ClasspathPattern extends AbstractSet<String>
             name=name.substring(0,name.length()-6);
         
         // Treat path elements as packages for name matching
-        name=name.replace("/",".");
+        name = name.replace('/', '.');
 
         return combine(_packageOrNamePatterns, name, _locations, ()->
         {

jetty-webapp/src/main/java/org/eclipse/jetty/webapp/WebInfConfiguration.java

@@ -38,6 +38,7 @@ import org.eclipse.jetty.server.Server;
 import org.eclipse.jetty.util.IO;
 import org.eclipse.jetty.util.JavaVersion;
 import org.eclipse.jetty.util.PatternMatcher;
+import org.eclipse.jetty.util.StringUtil;
 import org.eclipse.jetty.util.URIUtil;
 import org.eclipse.jetty.util.log.Log;
 import org.eclipse.jetty.util.log.Logger;
@@ -210,7 +211,8 @@ public class WebInfConfiguration extends AbstractConfiguration
                     }
                     catch (URISyntaxException e)
                     {
-                        containerUris.add(new URI(u.toString().replaceAll(" ", "%20")));
+                        String fixedUriStr = StringUtil.replace(u.toString(), " ", "%20");
+                        containerUris.add(new URI(fixedUriStr));
                     }
                 }
             }

tests/test-webapps/test-jetty-webapp/src/main/java/com/acme/CookieDump.java

@@ -21,7 +21,6 @@ package com.acme;
 import java.io.IOException;
 import java.io.PrintWriter;
 import java.util.concurrent.TimeUnit;
-
 import javax.servlet.RequestDispatcher;
 import javax.servlet.ServletException;
 import javax.servlet.http.Cookie;
@@ -29,7 +28,6 @@ import javax.servlet.http.HttpServlet;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
-
 /** 
  * Test Servlet Cookies.
  */
@@ -117,9 +115,9 @@ public class CookieDump extends HttpServlet
     {
         if (string==null)
             return null;
-        string=string.replace("&", "&");
+        string = string.replace("&", "&");
-        string=string.replace( "<", "&lt;");
+        string = string.replace( "<", "&lt;");
-        string=string.replace( ">", "&gt;");
+        string = string.replace( ">", "&gt;");
         return string;
     }
 

tests/test-webapps/test-jetty-webapp/src/main/java/com/acme/Dump.java

@@ -36,7 +36,6 @@ import java.util.Enumeration;
 import java.util.Locale;
 import java.util.Timer;
 import java.util.TimerTask;
-
 import javax.servlet.AsyncContext;
 import javax.servlet.AsyncEvent;
 import javax.servlet.AsyncListener;
@@ -57,13 +56,14 @@ import javax.servlet.http.HttpServletResponse;
 import javax.servlet.http.HttpServletResponseWrapper;
 import javax.servlet.http.Part;
 
-
+/**
-/** 
  * Dump Servlet Request.
  */
 @SuppressWarnings("serial")
 public class Dump extends HttpServlet
 {
+    /** Zero Width Space, to allow text to be wrapped at designated spots */
+    private static final String ZWSP = "​";
     boolean fixed;
     Timer _timer;
 
@@ -647,7 +647,7 @@ public class Dump extends HttpServlet
             {
                 name= (String)a.nextElement();
                 pout.write("</tr><tr>\n");
-                pout.write("<th align=\"right\" valign=\"top\">"+name.replace("."," .")+":&nbsp;</th>");
+                pout.write("<th align=\"right\" valign=\"top\">" + name.replace(".", ZWSP + ".") + ":&nbsp;</th>");
                 Object value=request.getAttribute(name);
                 if (value instanceof File)
                 {
@@ -678,7 +678,7 @@ public class Dump extends HttpServlet
             {
                 name= (String)a.nextElement();
                 pout.write("</tr><tr>\n");
-                pout.write("<th align=\"right\" valign=\"top\">"+name.replace("."," .")+":&nbsp;</th>");
+                pout.write("<th align=\"right\" valign=\"top\">" + name.replace(".", ZWSP + ".") + ":&nbsp;</th>");
                 pout.write("<td>"+ toString(getServletContext().getInitParameter(name)) + "</td>");
             }
 
@@ -689,7 +689,7 @@ public class Dump extends HttpServlet
             {
                 name= (String)a.nextElement();
                 pout.write("</tr><tr>\n");
-                pout.write("<th align=\"right\" valign=\"top\">"+name.replace("."," .")+":&nbsp;</th>");
+                pout.write("<th align=\"right\" valign=\"top\">" + name.replace(".", ZWSP + ".") + ":&nbsp;</th>");
                 pout.write("<td>"+"<pre>" + toString(getServletContext().getAttribute(name)) + "</pre>"+"</td>");
             }
 
@@ -1055,9 +1055,9 @@ public class Dump extends HttpServlet
     {
         if (s==null)
             return "null";
-        s=s.replaceAll("&","&amp;");
+        s = s.replace("&","&amp;");
-        s=s.replaceAll("<","&lt;");
+        s = s.replace("<","&lt;");
-        s=s.replaceAll(">","&gt;");
+        s = s.replace(">","&gt;");
         return s;
     }
 }