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diff --git a/third_party/checker_framework_dataflow/java/org/checkerframework/dataflow/analysis/Store.java b/third_party/checker_framework_dataflow/java/org/checkerframework/dataflow/analysis/Store.java
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+++ b/third_party/checker_framework_dataflow/java/org/checkerframework/dataflow/analysis/Store.java
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+package org.checkerframework.dataflow.analysis;
+
+import org.checkerframework.dataflow.cfg.CFGVisualizer;
+
+/**
+ * A store is used to keep track of the information that the org.checkerframework.dataflow analysis
+ * has accumulated at any given point in time.
+ *
+ * @author Stefan Heule
+ *
+ * @param <S>
+ *            The type of the store returned by {@code copy} and that is used in
+ *            {@code leastUpperBound}. Usually it is the implementing class
+ *            itself, e.g. in {@code T extends Store<T>}.
+ */
+public interface Store<S extends Store<S>> {
+
+    // We maintain a then store and an else store before each basic block.
+    // When they are identical (by reference equality), they can be treated
+    // as a regular unconditional store.
+    // Once we have some information for both the then and else store, we
+    // create a TransferInput for the block and allow it to be analyzed.
+    public static enum Kind {
+        THEN,
+        ELSE,
+        BOTH
+    }
+
+    /** A flow rule describes how stores flow along one edge between basic blocks. */
+    public static enum FlowRule {
+        EACH_TO_EACH,       // The normal case, then store flows to the then store
+                            // and else store flows to the else store.
+        THEN_TO_BOTH,       // Then store flows to both then and else of successor.
+        ELSE_TO_BOTH,       // Else store flows to both then and else of successor.
+        THEN_TO_THEN,       // Then store flows to the then of successor.  Else store is ignored.
+        ELSE_TO_ELSE,       // Else store flows to the else of successor.  Then store is ignored.
+    }
+
+    /** @return an exact copy of this store. */
+    S copy();
+
+    /**
+     * Compute the least upper bound of two stores.
+     *
+     * <p>
+     *
+     * <em>Important</em>: This method must fulfill the following contract:
+     * <ul>
+     * <li>Does not change {@code this}.</li>
+     * <li>Does not change {@code other}.</li>
+     * <li>Returns a fresh object which is not aliased yet.</li>
+     * <li>Returns an object of the same (dynamic) type as {@code this}, even if
+     * the signature is more permissive.</li>
+     * <li>Is commutative.</li>
+     * </ul>
+     */
+    S leastUpperBound(S other);
+
+    /**
+     * Can the objects {@code a} and {@code b} be aliases? Returns a
+     * conservative answer (i.e., returns {@code true} if not enough information
+     * is available to determine aliasing).
+     */
+    boolean canAlias(FlowExpressions.Receiver a,
+                     FlowExpressions.Receiver b);
+
+    /**
+     * Delegate visualization responsibility to a visualizer.
+     *
+     * @param viz the visualizer to visualize this store
+     */
+    void visualize(CFGVisualizer<?, S, ?> viz);
+}