417202 - Start / command line arguments with ${variable} should be expanded

+ Expanding properties & LIB references

jetty-start/src/main/java/org/eclipse/jetty/start/BaseHome.java

@@ -184,14 +184,26 @@ public class BaseHome
         if (homePath != null)
         {
             // logic if home is specified
-            this.homeDir = homePath;
+            this.homeDir = homePath.getAbsoluteFile();
-            this.baseDir = basePath == null?homePath:basePath;
+            if (basePath == null)
+            {
+                this.baseDir = homePath.getAbsoluteFile();
+                args.getProperties().setProperty("jetty.base",this.baseDir.toString(),"<internal-fallback>");
+            }
+            else
+            {
+                this.baseDir = basePath.getAbsoluteFile();
+            }
         }
         else if (basePath != null)
         {
             // logic if home is undeclared
-            this.baseDir = basePath;
+            this.baseDir = basePath.getAbsoluteFile();
         }
+
+        // Update System Properties
+        args.addSystemProperty("jetty.home",this.homeDir.getAbsolutePath());
+        args.addSystemProperty("jetty.base",this.baseDir.getAbsolutePath());
     }
 
     public boolean isBaseDifferent()

jetty-start/src/main/java/org/eclipse/jetty/start/Main.java

@@ -519,8 +519,6 @@ public class Main
 
         StartLog.debug("jetty.home=%s",baseHome.getHome());
         StartLog.debug("jetty.base=%s",baseHome.getBase());
-        args.addSystemProperty("jetty.home",baseHome.getHome());
-        args.addSystemProperty("jetty.base",baseHome.getBase());
 
         // ------------------------------------------------------------
         // 3) Load Inis
@@ -634,12 +632,12 @@ public class Main
 
         if (args.isStopCommand())
         {
-            int stopPort = Integer.parseInt(args.getProperties().getProperty("STOP.PORT"));
+            int stopPort = Integer.parseInt(args.getProperties().getString("STOP.PORT"));
-            String stopKey = args.getProperties().getProperty("STOP.KEY");
+            String stopKey = args.getProperties().getString("STOP.KEY");
 
-            if (args.getProperties().getProperty("STOP.WAIT") != null)
+            if (args.getProperties().getString("STOP.WAIT") != null)
             {
-                int stopWait = Integer.parseInt(args.getProperties().getProperty("STOP.PORT"));
+                int stopWait = Integer.parseInt(args.getProperties().getString("STOP.PORT"));
 
                 stop(stopPort,stopKey,stopWait);
             }

jetty-start/src/main/java/org/eclipse/jetty/start/ModuleGraphWriter.java

@@ -24,7 +24,6 @@ import java.io.IOException;
 import java.io.PrintWriter;
 import java.util.Collection;
 import java.util.List;
-import java.util.Properties;
 
 /**
  * Generate a graphviz dot graph of the modules found
@@ -48,7 +47,7 @@ public class ModuleGraphWriter
         colorModuleFont = "#888888";
     }
 
-    public void config(Properties props)
+    public void config(Props props)
     {
         String prefix = "jetty.graph.";
         colorModuleBg = getProperty(props,prefix + "color.module.bg",colorModuleBg);
@@ -59,9 +58,9 @@ public class ModuleGraphWriter
         colorModuleFont = getProperty(props,prefix + "color.font",colorModuleFont);
     }
 
-    private String getProperty(Properties props, String key, String defVal)
+    private String getProperty(Props props, String key, String defVal)
     {
-        String val = props.getProperty(key,defVal);
+        String val = props.getString(key,defVal);
         if (val == null)
         {
             return defVal;

jetty-start/src/main/java/org/eclipse/jetty/start/Props.java

@@ -0,0 +1,258 @@
+//
+//  ========================================================================
+//  Copyright (c) 1995-2013 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.start;
+
+import java.io.IOException;
+import java.io.OutputStream;
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.Map;
+import java.util.Properties;
+import java.util.Stack;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+import org.eclipse.jetty.start.Props.Prop;
+
+/**
+ * Management of Properties.
+ * <p>
+ * This is larger in scope than the standard {@link java.util.Properties}, as it will also handle tracking the origin of each property, if it was overridden,
+ * and also allowing for <code>${property}</code> expansion.
+ */
+public final class Props implements Iterable<Prop>
+{
+    public static class Prop
+    {
+        public String key;
+        public String value;
+        public String origin;
+        public Prop overrides;
+
+        public Prop(String key, String value, String origin)
+        {
+            this.key = key;
+            this.value = value;
+            this.origin = origin;
+        }
+
+        public Prop(String key, String value, String origin, Prop overrides)
+        {
+            this(key,value,origin);
+            this.overrides = overrides;
+        }
+    }
+
+    public static final String ORIGIN_SYSPROP = "<system-property>";
+
+    private Map<String, Prop> props = new HashMap<>();
+
+    public String cleanReference(String property)
+    {
+        String name = property.trim();
+        if (name.startsWith("${") && name.endsWith("}"))
+        {
+            name = name.substring(2,name.length() - 1);
+        }
+        return name.trim();
+    }
+
+    public boolean containsKey(String key)
+    {
+        return props.containsKey(key);
+    }
+
+    public String expand(String str)
+    {
+        return expand(str,new Stack<String>());
+    }
+
+    public String expand(String str, Stack<String> seenStack)
+    {
+        if (str == null)
+        {
+            return str;
+        }
+
+        if (str.indexOf("${") < 0)
+        {
+            // Contains no potential expressions.
+            return str;
+        }
+
+        if (props.isEmpty())
+        {
+            // This is a stupid programming error, we should have something, even system properties
+            throw new PropsException("Props is empty: no properties declared!?");
+        }
+
+        Pattern pat = Pattern.compile("(?<=[^$]|^)(\\$\\{[^}]*\\})");
+        Matcher mat = pat.matcher(str);
+        StringBuilder expanded = new StringBuilder();
+        int offset = 0;
+        String property;
+        String value;
+
+        while (mat.find(offset))
+        {
+            property = cleanReference(mat.group(1));
+
+            // Loop detection
+            if (seenStack.contains(property))
+            {
+                StringBuilder err = new StringBuilder();
+                err.append("Property expansion loop detected: ");
+                int idx = seenStack.lastIndexOf(property);
+                for (int i = idx; i < seenStack.size(); i++)
+                {
+                    err.append(seenStack.get(i));
+                    err.append(" -> ");
+                }
+                err.append(property);
+                throw new PropsException(err.toString());
+            }
+
+            seenStack.push(property);
+
+            // find property name
+            expanded.append(str.subSequence(offset,mat.start(1)));
+            // get property value
+            value = getString(property);
+            if (value == null)
+            {
+                StartLog.debug("Unable to expand: %s",property);
+                expanded.append(property);
+            }
+            else
+            {
+                // recursively expand
+                value = expand(value,seenStack);
+                expanded.append(value);
+            }
+            // update offset
+            offset = mat.end(1);
+        }
+
+        // leftover
+        expanded.append(str.substring(offset));
+
+        // special case for "$$"
+        if (expanded.indexOf("$$") >= 0)
+        {
+            return expanded.toString().replace("\\$\\$","\\$");
+        }
+
+        return expanded.toString();
+    }
+
+    public Prop getProp(String key)
+    {
+        Prop prop = props.get(key);
+        if (prop == null)
+        {
+            // try system property
+            prop = getSystemProperty(key);
+        }
+        return prop;
+    }
+
+    public String getString(String key)
+    {
+        if (key == null)
+        {
+            throw new PropsException("Cannot get value for null key");
+        }
+
+        String name = cleanReference(key);
+
+        if (name.length() == 0)
+        {
+            throw new PropsException("Cannot get value for empty key");
+        }
+
+        Prop prop = getProp(name);
+        if (prop == null)
+        {
+            return null;
+        }
+        return prop.value;
+    }
+
+    public String getString(String key, String defVal)
+    {
+        String val = getString(key);
+        if (val == null)
+        {
+            return defVal;
+        }
+        return val;
+    }
+
+    private Prop getSystemProperty(String key)
+    {
+        String value = System.getProperty(key);
+        if (value == null)
+        {
+            return null;
+        }
+        return new Prop(key,value,ORIGIN_SYSPROP);
+    }
+
+    @Override
+    public Iterator<Prop> iterator()
+    {
+        return props.values().iterator();
+    }
+
+    public void setProperty(Prop prop)
+    {
+        props.put(prop.key,prop);
+    }
+
+    public void setProperty(String key, String value, String origin)
+    {
+        Prop prop = props.get(key);
+        if (prop == null)
+        {
+            prop = new Prop(key,value,origin);
+        }
+        else
+        {
+            prop = new Prop(key,value,origin,prop);
+        }
+        props.put(key,prop);
+    }
+
+    public int size()
+    {
+        return props.size();
+    }
+
+    public void store(OutputStream stream, String comments) throws IOException
+    {
+        Properties props = new Properties();
+        // add all Props as normal properties, with expansion performed.
+        for (Prop prop : this)
+        {
+            props.setProperty(prop.key,expand(prop.value));
+        }
+        // write normal properties file
+        props.store(stream,comments);
+    }
+}

jetty-start/src/main/java/org/eclipse/jetty/start/PropsException.java

@@ -0,0 +1,41 @@
+//
+//  ========================================================================
+//  Copyright (c) 1995-2013 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.start;
+
+/**
+ * An non-recoverable error with Props usage
+ */
+@SuppressWarnings("serial")
+public class PropsException extends RuntimeException
+{
+    public PropsException(String message, Throwable cause)
+    {
+        super(message,cause);
+    }
+
+    public PropsException(String message)
+    {
+        super(message);
+    }
+
+    public PropsException(Throwable cause)
+    {
+        super(cause);
+    }
+}

jetty-start/src/main/java/org/eclipse/jetty/start/StartArgs.java

@@ -18,7 +18,7 @@
 
 package org.eclipse.jetty.start;
 
-import static org.eclipse.jetty.start.UsageException.ERR_BAD_ARG;
+import static org.eclipse.jetty.start.UsageException.*;
 
 import java.io.File;
 import java.io.FileFilter;
@@ -27,20 +27,20 @@ import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
-import java.util.Enumeration;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
-import java.util.Properties;
 import java.util.Set;
 
+import org.eclipse.jetty.start.Props.Prop;
+
 /**
  * The Arguments required to start Jetty.
  */
 public class StartArgs
 {
-    public static final String CMD_LINE_SOURCE = "<cmd-line>";
+    public static final String CMD_LINE_SOURCE = "<command-line>";
     public static final String VERSION;
 
     static
@@ -74,7 +74,7 @@ public class StartArgs
     private Classpath classpath;
     private List<String> xmlRefs = new ArrayList<>();
     private List<File> xmls = new ArrayList<>();
-    private Properties properties = new Properties();
+    private Props properties = new Props();
     private Set<String> systemPropertyKeys = new HashSet<>();
     private List<String> jvmArgs = new ArrayList<>();
     private List<String> moduleStartdIni = new ArrayList<>();
@@ -170,9 +170,9 @@ public class StartArgs
         System.out.println("Jetty Environment:");
         System.out.println("-----------------");
 
-        dumpSystemProperty("jetty.home");
+        dumpProperty("jetty.home");
-        dumpSystemProperty("jetty.base");
+        dumpProperty("jetty.base");
-        dumpSystemProperty("jetty.version");
+        dumpProperty("jetty.version");
     }
 
     public void dumpJvmArgs()
@@ -206,26 +206,27 @@ public class StartArgs
         System.out.println("Properties:");
         System.out.println("-----------");
 
-        if (properties.isEmpty())
+        List<String> sortedKeys = new ArrayList<>();
+        for (Prop prop : properties)
+        {
+            if (prop.origin.equals(Props.ORIGIN_SYSPROP))
+            {
+                continue; // skip
+            }
+            sortedKeys.add(prop.key);
+        }
+
+        if (sortedKeys.isEmpty())
         {
             System.out.println(" (no properties specified)");
             return;
         }
 
-        List<String> sortedKeys = new ArrayList<>();
-        @SuppressWarnings("unchecked")
-        Enumeration<String> keyEnum = (Enumeration<String>)properties.propertyNames();
-        while (keyEnum.hasMoreElements())
-        {
-            sortedKeys.add(keyEnum.nextElement());
-        }
-
         Collections.sort(sortedKeys);
 
         for (String key : sortedKeys)
         {
-            String value = properties.getProperty(key);
+            dumpProperty(key);
-            System.out.printf(" %s = %s%n",key,value);
         }
     }
 
@@ -248,13 +249,37 @@ public class StartArgs
         for (String key : sortedKeys)
         {
             String value = System.getProperty(key);
-            System.out.printf(" %s = %s%n",key,value);
+            System.out.printf(" %s = %s%n",key,properties.expand(value));
         }
     }
 
     private void dumpSystemProperty(String key)
     {
-        System.out.printf(" %s=%s%n",key,System.getProperty(key));
+        System.out.printf(" %s = %s%n",key,System.getProperty(key));
+    }
+
+    private void dumpProperty(String key)
+    {
+        Prop prop = properties.getProp(key);
+        if (prop == null)
+        {
+            System.out.printf(" %s (not defined)%n",key);
+        }
+        else
+        {
+            System.out.printf(" %s = %s%n",key,properties.expand(prop.value));
+            if (StartLog.isDebugEnabled())
+            {
+                System.out.printf("   origin: %s%n",prop.origin);
+                while (prop.overrides != null)
+                {
+                    prop = prop.overrides;
+                    System.out.printf("   (overrides)%n");
+                    System.out.printf("     %s = %s%n",key,properties.expand(prop.value));
+                    System.out.printf("     origin: %s%n",prop.origin);
+                }
+            }
+        }
     }
 
     /**
@@ -272,7 +297,7 @@ public class StartArgs
 
         if (properties.containsKey(key))
         {
-            String val = properties.getProperty(key,null);
+            String val = properties.expand(properties.getString(key));
             if (val == null)
             {
                 return; // no value to set
@@ -297,7 +322,7 @@ public class StartArgs
             // Find and Expand Libraries
             for (String rawlibref : module.getLibs())
             {
-                String libref = rawlibref.replace("${jetty.version}",VERSION);
+                String libref = properties.expand(rawlibref);
                 libref = FS.separators(libref);
 
                 if (libref.contains("*"))
@@ -470,7 +495,7 @@ public class StartArgs
         return moduleStartIni;
     }
 
-    public Properties getProperties()
+    public Props getProperties()
     {
         return properties;
     }
@@ -573,6 +598,26 @@ public class StartArgs
         return listModules;
     }
 
+    private void setProperty(String key, String value, String source)
+    {
+        // Special / Prevent override from start.ini's
+        if (key.equals("jetty.home"))
+        {
+            properties.setProperty("jetty.home",System.getProperty("jetty.home"),source);
+            return;
+        }
+
+        // Special / Prevent override from start.ini's
+        if (key.equals("jetty.base"))
+        {
+            properties.setProperty("jetty.base",System.getProperty("jetty.base"),source);
+            return;
+        }
+
+        // Normal
+        properties.setProperty(key,value,source);
+    }
+
     public void setRun(boolean run)
     {
         this.run = run;
@@ -661,15 +706,15 @@ public class StartArgs
         if (arg.startsWith("--download="))
         {
             addFile(getValue(arg));
-            run=false;
+            run = false;
-            download=true;
+            download = true;
             return;
         }
 
         if (arg.equals("--create-files"))
         {
-            run=false;
+            run = false;
-            download=true;
+            download = true;
             return;
         }
 
@@ -775,9 +820,11 @@ public class StartArgs
             {
                 case 2:
                     System.setProperty(assign[0],assign[1]);
+                    setProperty(assign[0],assign[1],source);
                     break;
                 case 1:
                     System.setProperty(assign[0],"");
+                    setProperty(assign[0],"",source);
                     break;
                 default:
                     break;
@@ -823,7 +870,7 @@ public class StartArgs
                 StartLog.warn(warn.toString());
             }
 
-            properties.setProperty(key,value);
+            setProperty(key,value,source);
             return;
         }
 

jetty-start/src/test/java/org/eclipse/jetty/start/ConfigurationAssert.java

@@ -18,8 +18,7 @@
 
 package org.eclipse.jetty.start;
 
-import static org.hamcrest.Matchers.greaterThan;
+import static org.hamcrest.Matchers.*;
-import static org.hamcrest.Matchers.greaterThanOrEqualTo;
 
 import java.io.File;
 import java.io.FileNotFoundException;
@@ -28,11 +27,11 @@ import java.io.PrintWriter;
 import java.io.StringWriter;
 import java.util.ArrayList;
 import java.util.Collection;
-import java.util.Enumeration;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Set;
 
+import org.eclipse.jetty.start.Props.Prop;
 import org.eclipse.jetty.toolchain.test.MavenTestingUtils;
 import org.junit.Assert;
 
@@ -97,18 +96,15 @@ public class ConfigurationAssert
             }
         }
         List<String> actualProperties = new ArrayList<>();
-        @SuppressWarnings("unchecked")
+        for(Prop prop: args.getProperties())
-        Enumeration<String> nameEnum = (Enumeration<String>)args.getProperties().propertyNames();
-        while (nameEnum.hasMoreElements())
         {
-            String name = nameEnum.nextElement();
+            String name = prop.key;
-            if ("jetty.home".equals(name) || "jetty.base".equals(name))
+            if ("jetty.home".equals(name) || "jetty.base".equals(name) || prop.origin.equals(Props.ORIGIN_SYSPROP))
             {
                 // strip these out from assertion, to make assertions easier.
                 continue;
             }
-            String value = args.getProperties().getProperty(name);
+            actualProperties.add(prop.key + "=" + args.getProperties().expand(prop.value));
-            actualProperties.add(name + "=" + value);
         }
         assertContainsUnordered("Properties",expectedProperties,actualProperties);
 

jetty-start/src/test/java/org/eclipse/jetty/start/MainTest.java

@@ -64,9 +64,9 @@ public class MainTest
         System.err.println(args);
 
         //Assert.assertEquals("--stop should not build module tree", 0, args.getEnabledModules().size());
-        Assert.assertEquals("--stop missing port","10000",args.getProperties().get("STOP.PORT"));
+        Assert.assertEquals("--stop missing port","10000",args.getProperties().getString("STOP.PORT"));
-        Assert.assertEquals("--stop missing key","foo",args.getProperties().get("STOP.KEY"));
+        Assert.assertEquals("--stop missing key","foo",args.getProperties().getString("STOP.KEY"));
-        Assert.assertEquals("--stop missing wait","300",args.getProperties().get("STOP.WAIT"));
+        Assert.assertEquals("--stop missing wait","300",args.getProperties().getString("STOP.WAIT"));
     }
     
     @Test
@@ -76,6 +76,7 @@ public class MainTest
         addUseCasesHome(cmdLineArgs);
         cmdLineArgs.add("jetty.port=9090");
         cmdLineArgs.add("--list-config");
+        // cmdLineArgs.add("--debug");
 
         Main main = new Main();
         StartArgs args = main.processCommandLine(cmdLineArgs.toArray(new String[cmdLineArgs.size()]));

jetty-start/src/test/java/org/eclipse/jetty/start/PropsTest.java

@@ -0,0 +1,139 @@
+//
+//  ========================================================================
+//  Copyright (c) 1995-2013 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.start;
+
+import static org.hamcrest.Matchers.*;
+import static org.junit.Assert.*;
+
+import org.eclipse.jetty.start.Props.Prop;
+import org.junit.Test;
+
+public class PropsTest
+{
+    private static final String FROM_TEST = "(test)";
+
+    private void assertProp(String prefix, Prop prop, String expectedKey, String expectedValue, String expectedOrigin)
+    {
+        assertThat(prefix,prop,notNullValue());
+        assertThat(prefix + ".key",prop.key,is(expectedKey));
+        assertThat(prefix + ".value",prop.value,is(expectedValue));
+        assertThat(prefix + ".origin",prop.origin,is(expectedOrigin));
+    }
+
+    @Test
+    public void testSystemPropsOnly()
+    {
+        Props props = new Props();
+
+        String expected = System.getProperty("java.io.tmpdir");
+        assertThat("System Property",props.getString("java.io.tmpdir"),is(expected));
+
+        Prop prop = props.getProp("java.io.tmpdir");
+        assertProp("System Prop",prop,"java.io.tmpdir",expected,Props.ORIGIN_SYSPROP);
+        assertThat("System Prop.overrides",prop.overrides,nullValue());
+    }
+
+    @Test
+    public void testBasic()
+    {
+        Props props = new Props();
+        props.setProperty("name","jetty",FROM_TEST);
+
+        String prefix = "Basic";
+        assertThat(prefix,props.getString("name"),is("jetty"));
+
+        Prop prop = props.getProp("name");
+        assertProp(prefix,prop,"name","jetty",FROM_TEST);
+        assertThat(prefix + ".overrides",prop.overrides,nullValue());
+    }
+
+    @Test
+    public void testOverride()
+    {
+        Props props = new Props();
+        props.setProperty("name","jetty",FROM_TEST);
+        props.setProperty("name","projetty","(Pro-Jetty)");
+
+        String prefix = "Overriden";
+        assertThat(prefix,props.getString("name"),is("projetty"));
+
+        Prop prop = props.getProp("name");
+        assertProp(prefix,prop,"name","projetty","(Pro-Jetty)");
+        Prop older = prop.overrides;
+        assertThat(prefix + ".overrides",older,notNullValue());
+        assertProp(prefix + ".overridden",older,"name","jetty",FROM_TEST);
+        assertThat(prefix + ".overridden",older.overrides,nullValue());
+    }
+
+    @Test
+    public void testSimpleExpand()
+    {
+        Props props = new Props();
+        props.setProperty("name","jetty",FROM_TEST);
+        props.setProperty("version","9.1",FROM_TEST);
+
+        assertThat(props.expand("port=8080"),is("port=8080"));
+        assertThat(props.expand("jdk=${java.version}"),is("jdk=" + System.getProperty("java.version")));
+        assertThat(props.expand("id=${name}-${version}"),is("id=jetty-9.1"));
+    }
+
+    @Test
+    public void testNoExpandDoubleDollar()
+    {
+        Props props = new Props();
+        props.setProperty("http.port","8080",FROM_TEST);
+
+        // Should NOT expand double $$ symbols
+        assertThat(props.expand("port=$${http.port}"),is("port=$${http.port}"));
+        // Should expand
+        assertThat(props.expand("port=${http.port}"),is("port=8080"));
+    }
+
+    @Test
+    public void testExpandDeep()
+    {
+        Props props = new Props();
+        props.setProperty("name","jetty",FROM_TEST);
+        props.setProperty("version","9.1",FROM_TEST);
+        props.setProperty("id","${name}-${version}",FROM_TEST);
+
+        // Should expand
+        assertThat(props.expand("server-id=corporate-${id}"),is("server-id=corporate-jetty-9.1"));
+    }
+
+    @Test
+    public void testExpandLoop()
+    {
+        Props props = new Props();
+        props.setProperty("aa","${bb}",FROM_TEST);
+        props.setProperty("bb","${cc}",FROM_TEST);
+        props.setProperty("cc","${aa}",FROM_TEST);
+
+        try
+        {
+            // Should throw exception
+            props.expand("val=${aa}");
+            fail("Should have thrown a " + PropsException.class);
+        }
+        catch (PropsException e)
+        {
+            assertThat(e.getMessage(),is("Property expansion loop detected: aa -> bb -> cc -> aa"));
+        }
+    }
+}

jetty-start/src/test/java/org/eclipse/jetty/start/TestUseCases.java

@@ -30,7 +30,7 @@ import org.junit.Test;
  */
 public class TestUseCases
 {
-    private void assertUseCase(String homeName, String baseName, String assertName) throws Exception
+    private void assertUseCase(String homeName, String baseName, String assertName, String... cmdLineArgs) throws Exception
     {
         File homeDir = MavenTestingUtils.getTestResourceDir("usecases/" + homeName);
         File baseDir = MavenTestingUtils.getTestResourceDir("usecases/" + baseName);
@@ -39,6 +39,10 @@ public class TestUseCases
         List<String> cmdLine = new ArrayList<>();
         cmdLine.add("jetty.home=" + homeDir.getAbsolutePath());
         cmdLine.add("jetty.base=" + baseDir.getAbsolutePath());
+        for (String arg : cmdLineArgs)
+        {
+            cmdLine.add(arg);
+        }
         StartArgs args = main.processCommandLine(cmdLine);
         BaseHome baseHome = main.getBaseHome();
         ConfigurationAssert.assertConfiguration(baseHome,args,"usecases/" + assertName);
@@ -67,4 +71,16 @@ public class TestUseCases
     {
         assertUseCase("home","base.with.db","assert-with-db.txt");
     }
+
+    @Test
+    public void testWithPropsBasic() throws Exception
+    {
+        assertUseCase("home","base.props.basic","assert-props.basic.txt","port=9090");
+    }
+    
+    @Test
+    public void testWithPropsAgent() throws Exception
+    {
+        assertUseCase("home","base.props.agent","assert-props.agent.txt","java.vm.specification.version=1.6");
+    }
 }

jetty-start/src/test/resources/usecases/assert-props.agent.txt

@@ -0,0 +1,20 @@
+# The XMLs we expect (order is important)
+XML|${jetty.home}/etc/jetty-jmx.xml
+XML|${jetty.home}/etc/jetty.xml
+XML|${jetty.home}/etc/jetty-http.xml
+
+# The LIBs we expect (order is irrelevant)
+LIB|${jetty.home}/lib/jetty-continuation-TEST.jar
+LIB|${jetty.home}/lib/jetty-http-TEST.jar
+LIB|${jetty.home}/lib/jetty-io-TEST.jar
+LIB|${jetty.home}/lib/jetty-jmx-TEST.jar
+LIB|${jetty.home}/lib/jetty-schemas-3.1.jar
+LIB|${jetty.home}/lib/jetty-server-TEST.jar
+LIB|${jetty.home}/lib/jetty-util-TEST.jar
+LIB|${jetty.home}/lib/jetty-xml-TEST.jar
+LIB|${jetty.home}/lib/servlet-api-3.1.jar
+LIB|${jetty.base}/lib/agent-jdk-1.6.jar
+
+# The Properties we expect (order is irrelevant)
+PROP|jetty.port=9090
+PROP|java.vm.specification.version=1.6

jetty-start/src/test/resources/usecases/assert-props.basic.txt

@@ -0,0 +1,17 @@
+# The XMLs we expect (order is important)
+XML|${jetty.home}/etc/jetty.xml
+XML|${jetty.home}/etc/jetty-http.xml
+
+# The LIBs we expect (order is irrelevant)
+LIB|${jetty.home}/lib/jetty-continuation-TEST.jar
+LIB|${jetty.home}/lib/jetty-http-TEST.jar
+LIB|${jetty.home}/lib/jetty-io-TEST.jar
+LIB|${jetty.home}/lib/jetty-schemas-3.1.jar
+LIB|${jetty.home}/lib/jetty-server-TEST.jar
+LIB|${jetty.home}/lib/jetty-util-TEST.jar
+LIB|${jetty.home}/lib/jetty-xml-TEST.jar
+LIB|${jetty.home}/lib/servlet-api-3.1.jar
+
+# The Properties we expect (order is irrelevant)
+PROP|jetty.port=9090
+PROP|port=9090

jetty-start/src/test/resources/usecases/base.props.agent/modules/agent.mod

@@ -0,0 +1,8 @@
+
+[depend]
+server
+jmx
+
+[lib]
+lib/agent-jdk-${java.vm.specification.version}.jar
+

jetty-start/src/test/resources/usecases/base.props.agent/start.ini

@@ -0,0 +1,4 @@
+
+--module=http,agent
+
+jetty.port=9090

jetty-start/src/test/resources/usecases/base.props.basic/start.ini

@@ -0,0 +1,5 @@
+
+--module=server
+--module=http
+
+jetty.port=${port}