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diff --git a/generator/src/main/java/com/google/archivepatcher/generator/PreDiffPlan.java b/generator/src/main/java/com/google/archivepatcher/generator/PreDiffPlan.java
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+// Copyright 2016 Google Inc. All rights reserved.
+//
+// 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 com.google.archivepatcher.generator;
+
+import java.util.Iterator;
+import java.util.List;
+
+import com.google.archivepatcher.shared.JreDeflateParameters;
+import com.google.archivepatcher.shared.TypedRange;
+
+/**
+ * A plan for transforming the old and the new archive prior to running a diffing algorithm and for
+ * recompressing the delta-friendly new archive afterwards.
+ * <p>
+ * The plan for uncompressing the old file is a {@link List} of {@link TypedRange} entries with void
+ * metadata. This describes the chunks of the old file that need to be uncompressed prior to
+ * diffing, in file order. The file produced by executing this plan is the "delta-friendly" old
+ * archive.
+ * <p>
+ * The plan for uncompressing the new file is similarly a {@link List} of {@link TypedRange}
+ * entries, but this time the metadata is of the type {@link JreDeflateParameters}. This describes
+ * the chunks of the new file that need to be uncompressed prior to diffing, in file order. The
+ * {@link JreDeflateParameters} metadata indicate the settings that need to be used to generate the
+ * inverse transform (the delta friendly new file recompression plan; see below). The file produced
+ * by executing this plan is the "delta-friendly" new archive.
+ * <p>
+ * The plan for recompressing the delta-friendly new archive is again a {@link List} of
+ * {@link TypedRange} entries with {@link JreDeflateParameters} metadata. This describes the chunks
+ * of the delta-friendly new file that need to be recompressed after diffing, again in file order.
+ * The {@link JreDeflateParameters} metadata indicate the settings to use during recompression. The
+ * file produced by executing this plan is the new archive, i.e. it reverse the transform of the
+ * new file uncompression plan.
+ * <p>
+ * Finally, a {@link List} of all the {@link QualifiedRecommendation}s upon which all the plans are
+ * based is available via {@link #getQualifiedRecommendations()}.
+ */
+public class PreDiffPlan {
+  /**
+   * The plan for uncompressing the old file, in file order.
+   */
+  private final List<TypedRange<Void>> oldFileUncompressionPlan;
+
+  /**
+   * The plan for uncompressing the new file, in file order.
+   */
+  private final List<TypedRange<JreDeflateParameters>> newFileUncompressionPlan;
+
+  /**
+   * The plan for recompressing the delta-friendly new file, in file order.
+   */
+  private final List<TypedRange<JreDeflateParameters>> deltaFriendlyNewFileRecompressionPlan;
+
+  /**
+   * The recommendations upon which the plans are based.
+   */
+  private final List<QualifiedRecommendation> qualifiedRecommendations;
+
+  /**
+   * Constructs a new plan.
+   * @param qualifiedRecommendations the recommendations upon which the plans are based
+   * @param oldFileUncompressionPlan the plan for uncompressing the old file, in file order
+   * @param newFileUncompressionPlan the plan for uncompressing the new file, in file order
+   */
+  public PreDiffPlan(
+      List<QualifiedRecommendation> qualifiedRecommendations,
+      List<TypedRange<Void>> oldFileUncompressionPlan,
+      List<TypedRange<JreDeflateParameters>> newFileUncompressionPlan) {
+    this(qualifiedRecommendations, oldFileUncompressionPlan, newFileUncompressionPlan, null);
+  }
+
+  /**
+   * Constructs a new plan.
+   * @param qualifiedRecommendations the recommendations upon which the plans are based
+   * @param oldFileUncompressionPlan the plan for uncompressing the old file, in file order
+   * @param newFileUncompressionPlan the plan for uncompressing the new file, in file order
+   * @param deltaFriendlyNewFileRecompressionPlan the plan for recompression the delta-friendly new
+   * file, in file order
+   */
+  public PreDiffPlan(
+      List<QualifiedRecommendation> qualifiedRecommendations,
+      List<TypedRange<Void>> oldFileUncompressionPlan,
+      List<TypedRange<JreDeflateParameters>> newFileUncompressionPlan,
+      List<TypedRange<JreDeflateParameters>> deltaFriendlyNewFileRecompressionPlan) {
+    ensureOrdered(oldFileUncompressionPlan);
+    ensureOrdered(newFileUncompressionPlan);
+    ensureOrdered(deltaFriendlyNewFileRecompressionPlan);
+    this.qualifiedRecommendations = qualifiedRecommendations;
+    this.oldFileUncompressionPlan = oldFileUncompressionPlan;
+    this.newFileUncompressionPlan = newFileUncompressionPlan;
+    this.deltaFriendlyNewFileRecompressionPlan = deltaFriendlyNewFileRecompressionPlan;
+  }
+
+  /**
+   * Ensures that the lists passed into the constructors are ordered and throws an exception if
+   * they are not. Null lists and lists whose size is less than 2 are ignored.
+   * @param list the list to check
+   */
+  private <T> void ensureOrdered(List<TypedRange<T>> list) {
+    if (list != null && list.size() >= 2) {
+      Iterator<TypedRange<T>> iterator = list.iterator();
+      TypedRange<T> lastEntry = iterator.next();
+      while (iterator.hasNext()) {
+        TypedRange<T> nextEntry = iterator.next();
+        if (lastEntry.compareTo(nextEntry) > 0) {
+          throw new IllegalArgumentException("List must be ordered");
+        }
+      }
+    }
+  }
+
+  /**
+   * Returns the plan for uncompressing the old file to create the delta-friendly old file.
+   * @return the plan
+   */
+  public final List<TypedRange<Void>> getOldFileUncompressionPlan() {
+    return oldFileUncompressionPlan;
+  }
+
+  /**
+   * Returns the plan for uncompressing the new file to create the delta-friendly new file.
+   * @return the plan
+   */
+  public final List<TypedRange<JreDeflateParameters>> getNewFileUncompressionPlan() {
+    return newFileUncompressionPlan;
+  }
+
+  /**
+   * Returns the plan for recompressing the delta-friendly new file to regenerate the original new
+   * file.
+   * @return the plan
+   */
+  public final List<TypedRange<JreDeflateParameters>> getDeltaFriendlyNewFileRecompressionPlan() {
+    return deltaFriendlyNewFileRecompressionPlan;
+  }
+
+  /**
+   * Returns the recommendations upon which the plans are based.
+   * @return the recommendations
+   */
+  public final List<QualifiedRecommendation> getQualifiedRecommendations() {
+    return qualifiedRecommendations;
+  }
+}