Add the new class Attributes holding multiple Attribute(s)

Attributes represents a semantic collector of Attribute(s) and replaces
the anonymous Map<String,Attribute>. This class will be returned by
TreeWalk.getAttributes(). It offers convenient access to the attributes
wrapped in the Attributes object. Adds preparations for a future
Attribute Macro Expansion

Change-Id: I8348c8c457a2a7f1f0c48050e10399b0fa1cdbe1
Signed-off-by: Ivan Motsch <ivan.motsch@bsiag.com>

5 files changed, 243 insertions, 12 deletions

diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/attributes/Attribute.java b/org.eclipse.jgit/src/org/eclipse/jgit/attributes/Attribute.java
index d3ce685187..905ad76929 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/attributes/Attribute.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/attributes/Attribute.java
@@ -50,8 +50,10 @@ package org.eclipse.jgit.attributes;
  * <li>Set - represented by {@link State#SET}</li>
  * <li>Unset - represented by {@link State#UNSET}</li>
  * <li>Set to a value - represented by {@link State#CUSTOM}</li>
- * <li>Unspecified - <code>null</code> is used instead of an instance of this
- * class</li>
+ * <li>Unspecified - used to revert an attribute . This is crucial in order to
+ * mark an attribute as unspecified in the attributes map and thus preventing
+ * following (with lower priority) nodes from setting the attribute to a value
+ * at all</li>
  * </ul>
  * </p>
  *
@@ -61,6 +63,7 @@ public final class Attribute {
 
 	/**
 	 * The attribute value state
+	 * see also https://www.kernel.org/pub/software/scm/git/docs/gitattributes.html
 	 */
 	public static enum State {
 		/** the attribute is set */
@@ -69,6 +72,13 @@ public final class Attribute {
 		/** the attribute is unset */
 		UNSET,
 
+		/**
+		 * the attribute appears as if it would not be defined at all
+		 *
+		 * @since 4.2
+		 */
+		UNSPECIFIED,
+
 		/** the attribute is set to a custom value */
 		CUSTOM
 	}
@@ -176,6 +186,8 @@ public final class Attribute {
 			return key;
 		case UNSET:
 			return "-" + key; //$NON-NLS-1$
+		case UNSPECIFIED:
+			return "!" + key; //$NON-NLS-1$
 		case CUSTOM:
 		default:
 			return key + "=" + value; //$NON-NLS-1$
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/attributes/Attributes.java b/org.eclipse.jgit/src/org/eclipse/jgit/attributes/Attributes.java
new file mode 100644
index 0000000000..0810e31682
--- /dev/null
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/attributes/Attributes.java
@@ -0,0 +1,202 @@
+/*
+ * Copyright (C) 2015, Ivan Motsch <ivan.motsch@bsiag.com>
+ *
+ * This program and the accompanying materials are made available
+ * under the terms of the Eclipse Distribution License v1.0 which
+ * accompanies this distribution, is reproduced below, and is
+ * available at http://www.eclipse.org/org/documents/edl-v10.php
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or
+ * without modification, are permitted provided that the following
+ * conditions are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above
+ *   copyright notice, this list of conditions and the following
+ *   disclaimer in the documentation and/or other materials provided
+ *   with the distribution.
+ *
+ * - Neither the name of the Eclipse Foundation, Inc. nor the
+ *   names of its contributors may be used to endorse or promote
+ *   products derived from this software without specific prior
+ *   written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
+ * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+package org.eclipse.jgit.attributes;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+import org.eclipse.jgit.attributes.Attribute.State;
+
+/**
+ * Represents a set of attributes for a path
+ * <p>
+ *
+ * @since 4.2
+ */
+public final class Attributes {
+	private final Map<String, Attribute> map = new LinkedHashMap<>();
+
+	/**
+	 * Creates a new instance
+	 *
+	 * @param attributes
+	 */
+	public Attributes(Attribute... attributes) {
+		if (attributes != null) {
+			for (Attribute a : attributes) {
+				put(a);
+			}
+		}
+	}
+
+	/**
+	 * @return true if the set does not contain any attributes
+	 */
+	public boolean isEmpty() {
+		return map.isEmpty();
+	}
+
+	/**
+	 * @param key
+	 * @return the attribute or null
+	 */
+	public Attribute get(String key) {
+		return map.get(key);
+	}
+
+	/**
+	 * @return all attributes
+	 */
+	public Collection<Attribute> getAll() {
+		return new ArrayList<>(map.values());
+	}
+
+	/**
+	 * @param a
+	 */
+	public void put(Attribute a) {
+		map.put(a.getKey(), a);
+	}
+
+	/**
+	 * @param key
+	 */
+	public void remove(String key) {
+		map.remove(key);
+	}
+
+	/**
+	 * @param key
+	 * @return true if the {@link Attributes} contains this key
+	 */
+	public boolean containsKey(String key) {
+		return map.containsKey(key);
+	}
+
+	/**
+	 * Returns the state.
+	 *
+	 * @param key
+	 *
+	 * @return the state (never returns <code>null</code>)
+	 */
+	public Attribute.State getState(String key) {
+		Attribute a = map.get(key);
+		return a != null ? a.getState() : Attribute.State.UNSPECIFIED;
+	}
+
+	/**
+	 * @param key
+	 * @return true if the key is {@link State#SET}, false in all other cases
+	 */
+	public boolean isSet(String key) {
+		return (getState(key) == State.SET);
+	}
+
+	/**
+	 * @param key
+	 * @return true if the key is {@link State#UNSET}, false in all other cases
+	 */
+	public boolean isUnset(String key) {
+		return (getState(key) == State.UNSET);
+	}
+
+	/**
+	 * @param key
+	 * @return true if the key is {@link State#UNSPECIFIED}, false in all other
+	 *         cases
+	 */
+	public boolean isUnspecified(String key) {
+		return (getState(key) == State.UNSPECIFIED);
+	}
+
+	/**
+	 * @param key
+	 * @return true if the key is {@link State#CUSTOM}, false in all other cases
+	 *         see {@link #getValue(String)} for the value of the key
+	 */
+	public boolean isCustom(String key) {
+		return (getState(key) == State.CUSTOM);
+	}
+
+	/**
+	 * @param key
+	 * @return the attribute value (may be <code>null</code>)
+	 */
+	public String getValue(String key) {
+		Attribute a = map.get(key);
+		return a != null ? a.getValue() : null;
+	}
+
+	@Override
+	public String toString() {
+		StringBuilder buf = new StringBuilder();
+		buf.append(getClass().getSimpleName());
+		buf.append("["); //$NON-NLS-1$
+		buf.append(" "); //$NON-NLS-1$
+		for (Attribute a : map.values()) {
+			buf.append(a.toString());
+			buf.append(" "); //$NON-NLS-1$
+		}
+		buf.append("]"); //$NON-NLS-1$
+		return buf.toString();
+	}
+
+	@Override
+	public int hashCode() {
+		return map.hashCode();
+	}
+
+	@Override
+	public boolean equals(Object obj) {
+		if (this == obj)
+			return true;
+		if (!(obj instanceof Attributes))
+			return false;
+		Attributes other = (Attributes) obj;
+		return this.map.equals(other.map);
+	}
+
+}
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/attributes/AttributesNode.java b/org.eclipse.jgit/src/org/eclipse/jgit/attributes/AttributesNode.java
index 70f56ff964..5c0aba2e0e 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/attributes/AttributesNode.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/attributes/AttributesNode.java
@@ -50,7 +50,6 @@ import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
 import java.util.ListIterator;
-import java.util.Map;
 
 import org.eclipse.jgit.lib.Constants;
 
@@ -134,11 +133,12 @@ public class AttributesNode {
 	 *            true if the target item is a directory.
 	 * @param attributes
 	 *            Map that will hold the attributes matching this entry path. If
-	 *            it is not empty, this method will NOT override any
-	 *            existing entry.
+	 *            it is not empty, this method will NOT override any existing
+	 *            entry.
+	 * @since 4.2
 	 */
-	public void getAttributes(String entryPath, boolean isDirectory,
-			Map<String, Attribute> attributes) {
+	public void getAttributes(String entryPath,
+			boolean isDirectory, Attributes attributes) {
 		// Parse rules in the reverse order that they were read since the last
 		// entry should be used
 		ListIterator<AttributesRule> ruleIterator = rules.listIterator(rules
@@ -153,7 +153,7 @@ public class AttributesNode {
 				while (attributeIte.hasPrevious()) {
 					Attribute attr = attributeIte.previous();
 					if (!attributes.containsKey(attr.getKey()))
-						attributes.put(attr.getKey(), attr);
+						attributes.put(attr);
 				}
 			}
 		}
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/attributes/AttributesProvider.java b/org.eclipse.jgit/src/org/eclipse/jgit/attributes/AttributesProvider.java
index 8f23a83f78..1037f697d4 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/attributes/AttributesProvider.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/attributes/AttributesProvider.java
@@ -42,8 +42,6 @@
  */
 package org.eclipse.jgit.attributes;
 
-import java.util.Map;
-
 /**
  * Interface for classes which provide git attributes
  *
@@ -51,7 +49,7 @@ import java.util.Map;
  */
 public interface AttributesProvider {
 	/**
-	 * @return the currently active attributes by attribute key
+	 * @return the currently active attributes
 	 */
-	public Map<String, Attribute> getAttributes();
+	public Attributes getAttributes();
 }
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/attributes/AttributesRule.java b/org.eclipse.jgit/src/org/eclipse/jgit/attributes/AttributesRule.java
index bcac14b5ff..35d18c4b2a 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/attributes/AttributesRule.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/attributes/AttributesRule.java
@@ -84,6 +84,13 @@ public class AttributesRule {
 				continue;
 			}
 
+			if (attribute.startsWith("!")) {//$NON-NLS-1$
+				if (attribute.length() > 1)
+					result.add(new Attribute(attribute.substring(1),
+							State.UNSPECIFIED));
+				continue;
+			}
+
 			final int equalsIndex = attribute.indexOf("="); //$NON-NLS-1$
 			if (equalsIndex == -1)
 				result.add(new Attribute(attribute, State.SET));
@@ -200,4 +207,16 @@ public class AttributesRule {
 		boolean match = matcher.matches(relativeTarget, isDirectory);
 		return match;
 	}
+
+	@Override
+	public String toString() {
+		StringBuilder sb = new StringBuilder();
+		sb.append(pattern);
+		for (Attribute a : attributes) {
+			sb.append(" "); //$NON-NLS-1$
+			sb.append(a);
+		}
+		return sb.toString();
+
+	}
 }
\ No newline at end of file