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diff --git a/src/main/java/org/apache/commons/lang3/builder/DiffResult.java b/src/main/java/org/apache/commons/lang3/builder/DiffResult.java
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+/*
+ * 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.
+ */
+package org.apache.commons.lang3.builder;
+
+import java.util.Collections;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Objects;
+
+/**
+ * A {@link DiffResult} contains a collection of the differences between two
+ * {@link Diffable} objects. Typically these differences are displayed using
+ * {@link #toString()} method, which returns a string describing the fields that
+ * differ between the objects.
+ *
+ * <p>
+ * Use a {@link DiffBuilder} to build a {@link DiffResult} comparing two objects.
+ * </p>
+ * @param <T> type of the left and right object.
+ *
+ * @since 3.3
+ */
+public class DiffResult<T> implements Iterable<Diff<?>> {
+
+    /**
+     * The {@link String} returned when the objects have no differences:
+     * {@value}
+     *
+     */
+    public static final String OBJECTS_SAME_STRING = "";
+
+    private static final String DIFFERS_STRING = "differs from";
+
+    private final List<Diff<?>> diffList;
+    private final T lhs;
+    private final T rhs;
+    private final ToStringStyle style;
+
+    /**
+     * Creates a {@link DiffResult} containing the differences between two
+     * objects.
+     *
+     * @param lhs
+     *            the left-hand object
+     * @param rhs
+     *            the right-hand object
+     * @param diffList
+     *            the list of differences, may be empty
+     * @param style
+     *            the style to use for the {@link #toString()} method. May be
+     *            {@code null}, in which case
+     *            {@link ToStringStyle#DEFAULT_STYLE} is used
+     * @throws NullPointerException if {@code lhs}, {@code rhs} or {@code diffs} is {@code null}
+     */
+    DiffResult(final T lhs, final T rhs, final List<Diff<?>> diffList,
+            final ToStringStyle style) {
+        Objects.requireNonNull(lhs, "lhs");
+        Objects.requireNonNull(rhs, "rhs");
+        Objects.requireNonNull(diffList, "diffList");
+
+        this.diffList = diffList;
+        this.lhs = lhs;
+        this.rhs = rhs;
+
+        if (style == null) {
+            this.style = ToStringStyle.DEFAULT_STYLE;
+        } else {
+            this.style = style;
+        }
+    }
+
+    /**
+     * Returns the object the right object has been compared to.
+     *
+     * @return the left object of the diff
+     * @since 3.10
+     */
+    public T getLeft() {
+        return this.lhs;
+    }
+
+    /**
+     * Returns the object the left object has been compared to.
+     *
+     * @return the right object of the diff
+     * @since 3.10
+     */
+    public T getRight() {
+        return this.rhs;
+    }
+
+    /**
+     * Returns an unmodifiable list of {@link Diff}s. The list may be empty if
+     * there were no differences between the objects.
+     *
+     * @return an unmodifiable list of {@link Diff}s
+     */
+    public List<Diff<?>> getDiffs() {
+        return Collections.unmodifiableList(diffList);
+    }
+
+    /**
+     * Returns the number of differences between the two objects.
+     *
+     * @return the number of differences
+     */
+    public int getNumberOfDiffs() {
+        return diffList.size();
+    }
+
+    /**
+     * Returns the style used by the {@link #toString()} method.
+     *
+     * @return the style
+     */
+    public ToStringStyle getToStringStyle() {
+        return style;
+    }
+
+    /**
+     * Builds a {@link String} description of the differences contained within
+     * this {@link DiffResult}. A {@link ToStringBuilder} is used for each object
+     * and the style of the output is governed by the {@link ToStringStyle}
+     * passed to the constructor.
+     *
+     * <p>
+     * If there are no differences stored in this list, the method will return
+     * {@link #OBJECTS_SAME_STRING}. Otherwise, using the example given in
+     * {@link Diffable} and {@link ToStringStyle#SHORT_PREFIX_STYLE}, an output
+     * might be:
+     * </p>
+     *
+     * <pre>
+     * Person[name=John Doe,age=32] differs from Person[name=Joe Bloggs,age=26]
+     * </pre>
+     *
+     * <p>
+     * This indicates that the objects differ in name and age, but not in
+     * smoking status.
+     * </p>
+     *
+     * <p>
+     * To use a different {@link ToStringStyle} for an instance of this class,
+     * use {@link #toString(ToStringStyle)}.
+     * </p>
+     *
+     * @return a {@link String} description of the differences.
+     */
+    @Override
+    public String toString() {
+        return toString(style);
+    }
+
+    /**
+     * Builds a {@link String} description of the differences contained within
+     * this {@link DiffResult}, using the supplied {@link ToStringStyle}.
+     *
+     * @param style
+     *            the {@link ToStringStyle} to use when outputting the objects
+     *
+     * @return a {@link String} description of the differences.
+     */
+    public String toString(final ToStringStyle style) {
+        if (diffList.isEmpty()) {
+            return OBJECTS_SAME_STRING;
+        }
+
+        final ToStringBuilder lhsBuilder = new ToStringBuilder(lhs, style);
+        final ToStringBuilder rhsBuilder = new ToStringBuilder(rhs, style);
+
+        diffList.forEach(diff -> {
+            lhsBuilder.append(diff.getFieldName(), diff.getLeft());
+            rhsBuilder.append(diff.getFieldName(), diff.getRight());
+        });
+
+        return String.format("%s %s %s", lhsBuilder.build(), DIFFERS_STRING, rhsBuilder.build());
+    }
+
+    /**
+     * Returns an iterator over the {@link Diff} objects contained in this list.
+     *
+     * @return the iterator
+     */
+    @Override
+    public Iterator<Diff<?>> iterator() {
+        return diffList.iterator();
+    }
+}