1 files changed, 180 insertions, 0 deletions
diff --git a/src/org/apache/http/message/BasicHeaderIterator.java b/src/org/apache/http/message/BasicHeaderIterator.java
new file mode 100644
index 0000000..32cd1c8
--- /dev/null
+++ b/src/org/apache/http/message/BasicHeaderIterator.java
@@ -0,0 +1,180 @@
+/*
+ * $HeadURL: http://svn.apache.org/repos/asf/httpcomponents/httpcore/trunk/module-main/src/main/java/org/apache/http/message/BasicHeaderIterator.java $
+ * $Revision: 581981 $
+ * $Date: 2007-10-04 11:26:26 -0700 (Thu, 04 Oct 2007) $
+ *
+ * ====================================================================
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ *
+ */
+
+package org.apache.http.message;
+
+
+import java.util.NoSuchElementException;
+
+import org.apache.http.Header;
+import org.apache.http.HeaderIterator;
+
+
+/**
+ * Basic implementation of a {@link HeaderIterator}.
+ * 
+ * @version $Revision: 581981 $
+ */
+public class BasicHeaderIterator implements HeaderIterator {
+
+    /**
+     * An array of headers to iterate over.
+     * Not all elements of this array are necessarily part of the iteration.
+     * This array will never be modified by the iterator.
+     * Derived implementations are expected to adhere to this restriction.
+     */
+    protected final Header[] allHeaders;
+
+
+    /**
+     * The position of the next header in {@link #allHeaders allHeaders}.
+     * Negative if the iteration is over.
+     */
+    protected int currentIndex;
+
+
+    /**
+     * The header name to filter by.
+     * <code>null</code> to iterate over all headers in the array.
+     */
+    protected String headerName;
+
+
+
+    /**
+     * Creates a new header iterator.
+     *
+     * @param headers   an array of headers over which to iterate
+     * @param name      the name of the headers over which to iterate, or
+     *                  <code>null</code> for any
+     */
+    public BasicHeaderIterator(Header[] headers, String name) {
+        if (headers == null) {
+            throw new IllegalArgumentException
+                ("Header array must not be null.");
+        }
+
+        this.allHeaders = headers;
+        this.headerName = name;
+        this.currentIndex = findNext(-1);
+    }
+
+
+    /**
+     * Determines the index of the next header.
+     *
+     * @param from      one less than the index to consider first,
+     *                  -1 to search for the first header
+     *
+     * @return  the index of the next header that matches the filter name,
+     *          or negative if there are no more headers
+     */
+    protected int findNext(int from) {
+        if (from < -1)
+            return -1;
+
+        final int to = this.allHeaders.length-1;
+        boolean found = false;
+        while (!found && (from < to)) {
+            from++;
+            found = filterHeader(from);
+        }
+        return found ? from : -1;
+    }
+
+
+    /**
+     * Checks whether a header is part of the iteration.
+     *
+     * @param index     the index of the header to check
+     *
+     * @return  <code>true</code> if the header should be part of the
+     *          iteration, <code>false</code> to skip
+     */
+    protected boolean filterHeader(int index) {
+        return (this.headerName == null) ||
+            this.headerName.equalsIgnoreCase(this.allHeaders[index].getName());
+    }
+
+
+    // non-javadoc, see interface HeaderIterator
+    public boolean hasNext() {
+        return (this.currentIndex >= 0);
+    }
+
+
+    /**
+     * Obtains the next header from this iteration.
+     *
+     * @return  the next header in this iteration
+     *
+     * @throws NoSuchElementException   if there are no more headers
+     */
+    public Header nextHeader()
+        throws NoSuchElementException {
+
+        final int current = this.currentIndex;
+        if (current < 0) {
+            throw new NoSuchElementException("Iteration already finished.");
+        }
+
+        this.currentIndex = findNext(current);
+
+        return this.allHeaders[current];
+    }
+
+
+    /**
+     * Returns the next header.
+     * Same as {@link #nextHeader nextHeader}, but not type-safe.
+     *
+     * @return  the next header in this iteration
+     *
+     * @throws NoSuchElementException   if there are no more headers
+     */
+    public final Object next()
+        throws NoSuchElementException {
+        return nextHeader();
+    }
+
+
+    /**
+     * Removing headers is not supported.
+     *
+     * @throws UnsupportedOperationException    always
+     */
+    public void remove()
+        throws UnsupportedOperationException {
+
+        throw new UnsupportedOperationException
+            ("Removing headers is not supported.");
+    }
+}