Merge pull request #216 from basil/iterators

Inline Guava's `Iterators#limit`

core/src/main/java/org/kohsuke/stapler/export/Iterators.java

@@ -0,0 +1,79 @@
+/*
+ * Copyright (C) 2007 The Guava Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.kohsuke.stapler.export;
+
+import java.util.Iterator;
+import java.util.NoSuchElementException;
+
+/**
+ * This class contains static utility methods that operate on or return objects of type {@link
+ * Iterator}.
+ *
+ * <p><i>Performance notes:</i> Unless otherwise noted, all of the iterators produced in this class
+ * are <i>lazy</i>, which means that they only advance the backing iteration when absolutely
+ * necessary.
+ *
+ * <p>See the Guava User Guide section on <a href=
+ * "https://github.com/google/guava/wiki/CollectionUtilitiesExplained#iterables"> {@code
+ * Iterators}</a>.
+ *
+ * @author Kevin Bourrillion
+ * @author Jared Levy
+ */
+final class Iterators {
+  private Iterators() {}
+
+  /**
+   * Returns a view containing the first {@code limitSize} elements of {@code iterator}. If {@code
+   * iterator} contains fewer than {@code limitSize} elements, the returned view contains all of its
+   * elements. The returned iterator supports {@code remove()} if {@code iterator} does.
+   *
+   * @param iterator the iterator to limit
+   * @param limitSize the maximum number of elements in the returned iterator
+   * @throws IllegalArgumentException if {@code limitSize} is negative
+   */
+  static <T> Iterator<T> limit(final Iterator<T> iterator, final int limitSize) {
+    if (iterator == null) {
+      throw new NullPointerException();
+    }
+    if (limitSize < 0) {
+      throw new IllegalArgumentException("limit is negative");
+    }
+    return new Iterator<T>() {
+      private int count;
+
+      @Override
+      public boolean hasNext() {
+        return count < limitSize && iterator.hasNext();
+      }
+
+      @Override
+      public T next() {
+        if (!hasNext()) {
+          throw new NoSuchElementException();
+        }
+        count++;
+        return iterator.next();
+      }
+
+      @Override
+      public void remove() {
+        iterator.remove();
+      }
+    };
+  }
+}

core/src/main/java/org/kohsuke/stapler/export/Range.java

@@ -1,7 +1,5 @@
 package org.kohsuke.stapler.export;
 
-import com.google.common.collect.Iterators;
-
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Iterator;