Default values for properties in ini files

While this feature is not strictly needed, the patch contains some good code cleanups.  So it will be applied and then the default feature
removed in a subsequent commit.

2 files changed, 24 insertions, 6 deletions

diff --git a/jetty-start/src/main/java/org/eclipse/jetty/start/Props.java b/jetty-start/src/main/java/org/eclipse/jetty/start/Props.java
index 78cdaa43a1..65191c81f5 100644
--- a/jetty-start/src/main/java/org/eclipse/jetty/start/Props.java
+++ b/jetty-start/src/main/java/org/eclipse/jetty/start/Props.java
@@ -42,6 +42,9 @@ import org.eclipse.jetty.start.Props.Prop;
  */
 public final class Props implements Iterable<Prop>
 {
+    private static final Pattern __propertyPattern = Pattern.compile("(?<=[^$]|^)\\$\\{([^:}]*)(:=([^}]*))?\\}");
+    
+    
     public static class Prop
     {
         public String key;
@@ -200,8 +203,7 @@ public final class Props implements Iterable<Prop>
             return str;
         }
 
-        Pattern pat = Pattern.compile("(?<=[^$]|^)(\\$\\{[^}]*\\})");
-        Matcher mat = pat.matcher(str);
+        Matcher mat = __propertyPattern.matcher(str);
         StringBuilder expanded = new StringBuilder();
         int offset = 0;
         String property;
@@ -209,7 +211,8 @@ public final class Props implements Iterable<Prop>
 
         while (mat.find(offset))
         {
-            property = cleanReference(mat.group(1));
+            property = mat.group(1);
+            String dftValue = mat.groupCount()>2?mat.group(3):null;
 
             // Loop detection
             if (seenStack.contains(property))
@@ -229,13 +232,15 @@ public final class Props implements Iterable<Prop>
             seenStack.push(property);
 
             // find property name
-            expanded.append(str.subSequence(offset,mat.start(1)));
+            expanded.append(str.subSequence(offset,mat.start()));
             // get property value
             value = getString(property);
+            if (value==null)
+                value=dftValue;
             if (value == null)
             {
                 StartLog.trace("Unable to expand: %s",property);
-                expanded.append(mat.group(1));
+                expanded.append(mat.group());
             }
             else
             {
@@ -244,7 +249,7 @@ public final class Props implements Iterable<Prop>
                 expanded.append(value);
             }
             // update offset
-            offset = mat.end(1);
+            offset = mat.end();
         }
 
         // leftover
diff --git a/jetty-start/src/test/java/org/eclipse/jetty/start/PropsTest.java b/jetty-start/src/test/java/org/eclipse/jetty/start/PropsTest.java
index f7c9ee1039..0151f3b61a 100644
--- a/jetty-start/src/test/java/org/eclipse/jetty/start/PropsTest.java
+++ b/jetty-start/src/test/java/org/eclipse/jetty/start/PropsTest.java
@@ -98,6 +98,19 @@ public class PropsTest
     }
 
     @Test
+    public void testSimpleExpandWithDefaults()
+    {
+        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=${java.version:=WRONG}"),is("jdk=" + System.getProperty("java.version")));
+        assertThat(props.expand("id=${name:=WRONG}-${version:=WRONG}"),is("id=jetty-9.1"));
+        assertThat(props.expand("id=${unknown:=UNKNOWN}-${wibble}"),is("id=UNKNOWN-${wibble}"));
+    }
+
+    @Test
     public void testNoExpandDoubleDollar()
     {
         Props props = new Props();