[256624] [UI] Create a Commit History ViewPart drops/I20121005-0745

https://bugs.eclipse.org/bugs/show_bug.cgi?id=256624

7 files changed, 290 insertions, 7 deletions

diff --git a/plugins/org.eclipse.net4j.util/src/org/eclipse/net4j/util/collection/AbstractFilteredIterator.java b/plugins/org.eclipse.net4j.util/src/org/eclipse/net4j/util/collection/AbstractFilteredIterator.java
new file mode 100644
index 0000000000..5b99bee3a8
--- /dev/null
+++ b/plugins/org.eclipse.net4j.util/src/org/eclipse/net4j/util/collection/AbstractFilteredIterator.java
@@ -0,0 +1,46 @@
+/*
+ * Copyright (c) 2004 - 2012 Eike Stepper (Berlin, Germany) and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *    Eike Stepper - initial API and implementation
+ */
+package org.eclipse.net4j.util.collection;
+
+import java.util.Iterator;
+
+/**
+ * An abstract base class for custom iterators that {@link #isValid(Object) filter} the elements of a delegate iterator.
+ *
+ * @author Eike Stepper
+ * @since 3.3
+ */
+public abstract class AbstractFilteredIterator<T> extends AbstractIterator<T>
+{
+  private Iterator<T> delegate;
+
+  public AbstractFilteredIterator(Iterator<T> delegate)
+  {
+    this.delegate = delegate;
+  }
+
+  @Override
+  protected Object computeNextElement()
+  {
+    while (delegate.hasNext())
+    {
+      T element = delegate.next();
+      if (isValid(element))
+      {
+        return element;
+      }
+    }
+
+    return END_OF_DATA;
+  }
+
+  protected abstract boolean isValid(T element);
+}
diff --git a/plugins/org.eclipse.net4j.util/src/org/eclipse/net4j/util/collection/AbstractIterator.java b/plugins/org.eclipse.net4j.util/src/org/eclipse/net4j/util/collection/AbstractIterator.java
index a503071784..a4bea4ee9e 100644
--- a/plugins/org.eclipse.net4j.util/src/org/eclipse/net4j/util/collection/AbstractIterator.java
+++ b/plugins/org.eclipse.net4j.util/src/org/eclipse/net4j/util/collection/AbstractIterator.java
@@ -14,9 +14,8 @@ import java.util.Iterator;
 import java.util.NoSuchElementException;
 
 /**
- * An abstract base class for custom iterators that only requires to implement a single {@link #computeNextElement()}
- * method.
- * 
+ * An abstract base class for custom iterators that only requires to implement a single {@link #computeNextElement()} method.
+ *
  * @author Eike Stepper
  * @since 3.2
  */
@@ -27,7 +26,7 @@ public abstract class AbstractIterator<T> implements Iterator<T>
    */
   protected static final Object END_OF_DATA = new Object();
 
-  private boolean computed;
+  private boolean nextComputed;
 
   private T next;
 
@@ -37,13 +36,13 @@ public abstract class AbstractIterator<T> implements Iterator<T>
 
   public final boolean hasNext()
   {
-    if (computed)
+    if (nextComputed)
     {
       return true;
     }
 
     Object object = computeNextElement();
-    computed = true;
+    nextComputed = true;
 
     if (object == END_OF_DATA)
     {
@@ -63,7 +62,7 @@ public abstract class AbstractIterator<T> implements Iterator<T>
       throw new NoSuchElementException();
     }
 
-    computed = false;
+    nextComputed = false;
     return next;
   }
 
diff --git a/plugins/org.eclipse.net4j.util/src/org/eclipse/net4j/util/collection/AbstractListIterator.java b/plugins/org.eclipse.net4j.util/src/org/eclipse/net4j/util/collection/AbstractListIterator.java
new file mode 100644
index 0000000000..7e031fdc2d
--- /dev/null
+++ b/plugins/org.eclipse.net4j.util/src/org/eclipse/net4j/util/collection/AbstractListIterator.java
@@ -0,0 +1,67 @@
+/*
+ * Copyright (c) 2004 - 2012 Eike Stepper (Berlin, Germany) and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *    Eike Stepper - initial API and implementation
+ */
+package org.eclipse.net4j.util.collection;
+
+import java.util.NoSuchElementException;
+
+/**
+ * An abstract base class for custom list iterators that only requires to implement the {@link #computeNextElement()} and {@link #computePreviousElement()} methods.
+ *
+ * @author Eike Stepper
+ * @since 3.3
+ */
+public abstract class AbstractListIterator<T> extends AbstractIterator<T>
+{
+  private boolean previousComputed;
+
+  private T previous;
+
+  public AbstractListIterator()
+  {
+  }
+
+  public final boolean hasPrevious()
+  {
+    if (previousComputed)
+    {
+      return true;
+    }
+
+    Object object = computeNextElement();
+    previousComputed = true;
+
+    if (object == END_OF_DATA)
+    {
+      return false;
+    }
+
+    @SuppressWarnings("unchecked")
+    T cast = (T)object;
+    previous = cast;
+    return true;
+  }
+
+  public final T previous()
+  {
+    if (!hasPrevious())
+    {
+      throw new NoSuchElementException();
+    }
+
+    previousComputed = false;
+    return previous;
+  }
+
+  /**
+   * Returns the previous iteration element, or {@link #END_OF_DATA} if the start of the iteration has been reached.
+   */
+  protected abstract Object computePreviousElement();
+}
diff --git a/plugins/org.eclipse.net4j.util/src/org/eclipse/net4j/util/collection/BidirectionalIterator.java b/plugins/org.eclipse.net4j.util/src/org/eclipse/net4j/util/collection/BidirectionalIterator.java
new file mode 100644
index 0000000000..713ab8a58e
--- /dev/null
+++ b/plugins/org.eclipse.net4j.util/src/org/eclipse/net4j/util/collection/BidirectionalIterator.java
@@ -0,0 +1,66 @@
+/*
+ * Copyright (c) 2004 - 2012 Eike Stepper (Berlin, Germany) and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *    Eike Stepper - initial API and implementation
+ */
+package org.eclipse.net4j.util.collection;
+
+import java.util.Iterator;
+import java.util.ListIterator;
+
+/**
+ * @author Eike Stepper
+ * @since 3.3
+ */
+public class BidirectionalIterator<T> implements Iterator<T>
+{
+  private final ListIterator<T> delegate;
+
+  private boolean backward;
+
+  public BidirectionalIterator(ListIterator<T> delegate, boolean backward)
+  {
+    this.delegate = delegate;
+    this.backward = backward;
+  }
+
+  public BidirectionalIterator(ListIterator<T> delegate)
+  {
+    this(delegate, false);
+  }
+
+  public ListIterator<T> getDelegate()
+  {
+    return delegate;
+  }
+
+  public boolean isBackward()
+  {
+    return backward;
+  }
+
+  public void setBackward(boolean backward)
+  {
+    this.backward = backward;
+  }
+
+  public boolean hasNext()
+  {
+    return backward ? delegate.hasPrevious() : delegate.hasNext();
+  }
+
+  public T next()
+  {
+    return backward ? delegate.previous() : delegate.next();
+  }
+
+  public void remove()
+  {
+    delegate.remove();
+  }
+}
diff --git a/plugins/org.eclipse.net4j.util/src/org/eclipse/net4j/util/collection/LimitedIterator.java b/plugins/org.eclipse.net4j.util/src/org/eclipse/net4j/util/collection/LimitedIterator.java
new file mode 100644
index 0000000000..44f72628e9
--- /dev/null
+++ b/plugins/org.eclipse.net4j.util/src/org/eclipse/net4j/util/collection/LimitedIterator.java
@@ -0,0 +1,46 @@
+/*
+ * Copyright (c) 2004 - 2012 Eike Stepper (Berlin, Germany) and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *    Eike Stepper - initial API and implementation
+ */
+package org.eclipse.net4j.util.collection;
+
+import java.util.Iterator;
+
+/**
+ * @author Eike Stepper
+ * @since 3.3
+ */
+public class LimitedIterator<T> extends AbstractFilteredIterator<T>
+{
+  private final int limit;
+
+  private int count;
+
+  public LimitedIterator(Iterator<T> delegate, int limit)
+  {
+    super(delegate);
+    this.limit = limit;
+  }
+
+  public final int getLimit()
+  {
+    return limit;
+  }
+
+  public final int getCount()
+  {
+    return count;
+  }
+
+  @Override
+  protected boolean isValid(T element)
+  {
+    return ++count <= limit;
+  }
+}
diff --git a/plugins/org.eclipse.net4j.util/src/org/eclipse/net4j/util/collection/Predicate.java b/plugins/org.eclipse.net4j.util/src/org/eclipse/net4j/util/collection/Predicate.java
new file mode 100644
index 0000000000..bd6d4de9e2
--- /dev/null
+++ b/plugins/org.eclipse.net4j.util/src/org/eclipse/net4j/util/collection/Predicate.java
@@ -0,0 +1,20 @@
+/*
+ * Copyright (c) 2004 - 2012 Eike Stepper (Berlin, Germany) and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *    Eike Stepper - initial API and implementation
+ */
+package org.eclipse.net4j.util.collection;
+
+/**
+ * @author Eike Stepper
+ * @since 3.3
+ */
+public interface Predicate<T>
+{
+  public boolean apply(T element);
+}
diff --git a/plugins/org.eclipse.net4j.util/src/org/eclipse/net4j/util/collection/PredicateIterator.java b/plugins/org.eclipse.net4j.util/src/org/eclipse/net4j/util/collection/PredicateIterator.java
new file mode 100644
index 0000000000..2a4b1a90d7
--- /dev/null
+++ b/plugins/org.eclipse.net4j.util/src/org/eclipse/net4j/util/collection/PredicateIterator.java
@@ -0,0 +1,39 @@
+/*
+ * Copyright (c) 2004 - 2012 Eike Stepper (Berlin, Germany) and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *    Eike Stepper - initial API and implementation
+ */
+package org.eclipse.net4j.util.collection;
+
+import java.util.Iterator;
+
+/**
+ * @author Eike Stepper
+ * @since 3.3
+ */
+public class PredicateIterator<T> extends AbstractFilteredIterator<T>
+{
+  private final Predicate<? super T> predicate;
+
+  public PredicateIterator(Iterator<T> delegate, Predicate<? super T> predicate)
+  {
+    super(delegate);
+    this.predicate = predicate;
+  }
+
+  public Predicate<? super T> getPredicate()
+  {
+    return predicate;
+  }
+
+  @Override
+  protected boolean isValid(T element)
+  {
+    return predicate.apply(element);
+  }
+}