Refactoring to support reverse variable matching for issue #2

pom.xml

@@ -1,4 +1,5 @@
-<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
 	<modelVersion>4.0.0</modelVersion>
 	<parent>
 		<groupId>org.sonatype.oss</groupId>
@@ -173,6 +174,25 @@
 				<groupId>org.apache.maven.plugins</groupId>
 				<artifactId>maven-site-plugin</artifactId>
 				<version>3.3</version>
+				<dependencies>
+					<dependency>
+						<groupId>lt.velykis.maven.skins</groupId>
+						<artifactId>reflow-velocity-tools</artifactId>
+						<version>1.0.0</version>
+					</dependency>
+					<!-- Reflow skin requires Velocity >= 1.7 -->
+					<dependency>
+						<groupId>org.apache.velocity</groupId>
+						<artifactId>velocity</artifactId>
+						<version>1.7</version>
+					</dependency>
+					<dependency>
+						<!-- Markdown support for writing website content -->
+						<groupId>org.apache.maven.doxia</groupId>
+						<artifactId>doxia-module-markdown</artifactId>
+						<version>1.3</version>
+					</dependency>
+				</dependencies>
 				<configuration>
 
 					<reportPlugins>
@@ -245,8 +265,8 @@
 				<groupId>org.apache.maven.plugins</groupId>
 				<artifactId>maven-compiler-plugin</artifactId>
 				<configuration>
-					<source>1.6</source>
-					<target>1.6</target>
+					<source>1.7</source>
+					<target>1.7</target>
 				</configuration>
 			</plugin>
 
@@ -287,7 +307,7 @@
 				<version>2.9.1</version>
 				<configuration>
 					<aggregate>true</aggregate>
-					<source>1.6</source>
+					<source>1.7</source>
 					<encoding>UTF-8</encoding>
 					<maxmemory>1g</maxmemory>
 					<links>
@@ -383,36 +403,36 @@
 			<version>4.11</version>
 			<scope>test</scope>
 		</dependency>
-	
-	
+
+
 		<!-- JSON -->
 		<dependency>
 			<groupId>com.fasterxml.jackson.core</groupId>
 			<artifactId>jackson-core</artifactId>
 			<version>${jackson.version}</version>
 			<optional>true</optional>
 		</dependency>
-	
+
 		<dependency>
 			<groupId>com.fasterxml.jackson.core</groupId>
 			<artifactId>jackson-databind</artifactId>
 			<version>${jackson.version}</version>
 			<optional>true</optional>
 		</dependency>
-	
+
 		<dependency>
 			<groupId>com.fasterxml.jackson.core</groupId>
 			<artifactId>jackson-annotations</artifactId>
 			<version>${jackson.version}</version>
 			<optional>true</optional>
 		</dependency>
 
-        <dependency>
-            <groupId>com.google.guava</groupId>
-            <artifactId>guava</artifactId>
-            <version>14.0.1</version>
-            <scope>test</scope>
-        </dependency>
+		<dependency>
+			<groupId>com.google.guava</groupId>
+			<artifactId>guava</artifactId>
+			<version>14.0.1</version>
+			<scope>test</scope>
+		</dependency>
 
 		<!-- Async HTTP Client -->
 		<dependency>
@@ -427,6 +447,12 @@
 			<version>4.2.5</version>
 			<scope>test</scope>
 		</dependency>
+		<dependency>
+			<groupId>org.apache.abdera</groupId>
+			<artifactId>abdera-i18n</artifactId>
+			<version>1.1.3</version>
+			<type>bundle</type>
+		</dependency>
 	</dependencies>
 
 

src/main/java/com/damnhandy/uri/template/Expression.java

@@ -57,7 +57,8 @@ public class Expression extends UriTemplateComponent
     */
    private static final Pattern VARNAME_REGEX = Pattern.compile("([\\w\\_\\.]|%[A-Fa-f0-9]{2})+");
    /**
-    * A regex quoted string that matches the expression. For example:
+    * A regex quoted string that matches the expression for replacement in the
+    * expansion process. For example:
     * <pre>
     *          \Q{?query,number}\E
     * </pre>
@@ -69,12 +70,20 @@ public class Expression extends UriTemplateComponent
     */
    private Operator op;
 
-
+   /**
+    * The character position where this expression occurs in the URI template
+    */
+   private final int location;
    /**
     * The the parsed {@link VarSpec} instances found in the expression.
     */
    private List<VarSpec> varSpecs;
 
+   /**
+    * The Patter that would be used to reverse match this expression 
+    */
+   private Pattern matchPattern;
+
 
    /**
     * Creates a new {@link Builder} to create a simple expression according
@@ -255,10 +264,11 @@ public static Builder continuation(VarSpec...varSpec)
     * @param op
     * @param varSpecs
     */
-   public Expression(final String rawExpression, int startPosition) throws MalformedUriTemplateException
+   public Expression(final String rawExpression, final int startPosition) throws MalformedUriTemplateException
    {
       super(startPosition);
-      this.parseRawExpression(rawExpression);
+      this.location = startPosition;
+      this.parseRawExpression(rawExpression);  
    }
 
    /**
@@ -275,6 +285,8 @@ public Expression(final Operator op, final List<VarSpec> varSpecs)
       this.op = op;
       this.varSpecs = varSpecs;
       this.replacementPattern = Pattern.quote(toString());
+      this.matchPattern = buildMatchingPattern();
+      this.location = 0;
    }
 
    /**
@@ -292,7 +304,14 @@ private void parseRawExpression(String rawExpression) throws MalformedUriTemplat
       String firstChar = token.substring(0, 1);
       if (UriTemplate.containsOperator(firstChar))
       {
-         operator = Operator.fromOpCode(firstChar);
+         try
+         {
+            operator = Operator.fromOpCode(firstChar);
+         }
+         catch (IllegalOperatorException e)
+         {
+            throw new MalformedUriTemplateException("Invalid operator" , this.location, e);
+         }
          token = token.substring(1, token.length());
       }
       String[] varspecStrings = token.split(",");
@@ -315,7 +334,7 @@ private void parseRawExpression(String rawExpression) throws MalformedUriTemplat
             }
             catch (NumberFormatException e)
             {
-               throw new MalformedUriTemplateException("The prefix value for "+ pair[0]+ " was not a number", e);
+               throw new MalformedUriTemplateException("The prefix value for "+ pair[0]+ " was not a number", this.location, e);
             }
          }
 
@@ -350,26 +369,45 @@ private void validateVarname(String varname) throws MalformedUriTemplateExceptio
       Matcher matcher = VARNAME_REGEX.matcher(varname);
       if(!matcher.matches())
       {
-         throw new MalformedUriTemplateException("The variable name "+varname+" contains invalid characters");
+         throw new MalformedUriTemplateException("The variable name "+varname+" contains invalid characters", this.location);
       }
 
       if(varname.contains(" "))
       {
-         throw new MalformedUriTemplateException("The variable name "+varname+" cannot contain spaces (leading or trailing)");
+         throw new MalformedUriTemplateException("The variable name "+varname+" cannot contain spaces (leading or trailing)", this.location);
       }
    }
 
 
+   /**
+    * 
+    *
+    * @return
+    */
+   private Pattern buildMatchingPattern()
+   {
+      StringBuilder b = new StringBuilder();
+      for(VarSpec v : getVarSpecs())
+      {
+         b.append("(?<").append(v.getVariableName()).append(">[^\\/]+)");
+      }
+      return Pattern.compile(b.toString());
+   }
+
    /**
     * Returns a string that contains a regular expression that matches the
     * URI template expression.
-    *
+    * 
     * @return
     */
-   public String buildMatchingPattern()
+   @Override
+   public Pattern getMatchPattern()
    {
-      StringBuilder builder = new StringBuilder();
-      return builder.toString();
+      if(this.matchPattern == null)
+      {
+         this.matchPattern = buildMatchingPattern();
+      }
+      return this.matchPattern;
    }
    /**
     * Get the replacementToken.

src/main/java/com/damnhandy/uri/template/IllegalOperatorException.java

@@ -0,0 +1,30 @@
+/*
+ *
+ *
+ */
+package com.damnhandy.uri.template;
+
+/**
+ * A IllegalOperatorException.
+ * 
+ * @author <a href="[email protected]">Ryan J. McDonough</a>
+ * @version $Revision: 1.1 $
+ */
+public class IllegalOperatorException extends Exception
+{
+
+   /** The serialVersionUID */
+   private static final long serialVersionUID = 7874128076415224267L;
+
+
+   /**
+    * Create a new IllegalOperatorException.
+    * 
+    * @param message
+    */
+   public IllegalOperatorException(String message)
+   {
+      super(message);
+   }
+
+}

src/main/java/com/damnhandy/uri/template/Literal.java

@@ -4,6 +4,8 @@
  */
 package com.damnhandy.uri.template;
 
+import java.util.regex.Pattern;
+
 /**
  * Represents the non-expression parts of a URI Template
  * 
@@ -16,9 +18,11 @@ public class Literal extends UriTemplateComponent
 
    /** The serialVersionUID */
    private static final long serialVersionUID = 6011009312823496878L;
-   
+
    private final String value;
 
+   private final Pattern matchPattern;
+
    /**
     * Create a new Literal.
     * 
@@ -27,6 +31,7 @@ public Literal(final String value, int startPosition)
    {
       super(startPosition);
       this.value = value;
+      this.matchPattern = Pattern.compile(Pattern.quote(getValue()));
    }
 
    @Override
@@ -41,4 +46,10 @@ public String toString()
       return value;
    }
 
+   @Override
+   public Pattern getMatchPattern()
+   {
+      return this.matchPattern;
+   }
+
 }

src/main/java/com/damnhandy/uri/template/MalformedUriTemplateException.java

@@ -17,7 +17,7 @@
 
 /**
  * Raised when the the template processor encounters an issue parsing the URI template string. It indicates
- * the template contains an expression that is malformed.
+ * the either the template itself is malformed, or an expression within the template is malformed.
  *
  * @author <a href="[email protected]">Ryan J. McDonough</a>
  * @version $Revision: 1.1 $
@@ -29,25 +29,32 @@ public class MalformedUriTemplateException extends Exception
    /** The serialVersionUID */
    private static final long serialVersionUID = 5883174281977078450L;
 
+   private int location;
    /**
     * Create a new UriTemplateParseException.
     *
     * @param message
     * @param cause
     */
-   public MalformedUriTemplateException(String message, Throwable cause)
+   public MalformedUriTemplateException(String message, int location, Throwable cause)
    {
       super(message, cause);
+      this.location = location;
    }
 
    /**
     * Create a new UriTemplateParseException.
     *
     * @param message
     */
-   public MalformedUriTemplateException(String message)
+   public MalformedUriTemplateException(String message, int location)
    {
       super(message);
+      this.location = location;
    }
 
+   public int getLocation() 
+   {
+      return this.location;
+   }
 }