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diff --git a/src/main/java/com/amazon/carbonado/qe/AbstractQuery.java b/src/main/java/com/amazon/carbonado/qe/AbstractQuery.java
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+/*
+ * Copyright 2006 Amazon Technologies, Inc. or its affiliates.
+ * Amazon, Amazon.com and Carbonado are trademarks or registered trademarks
+ * of Amazon Technologies, Inc. or its affiliates.  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.amazon.carbonado.qe;
+
+import java.io.IOException;
+import java.lang.reflect.UndeclaredThrowableException;
+
+import com.amazon.carbonado.Cursor;
+import com.amazon.carbonado.FetchException;
+import com.amazon.carbonado.FetchMultipleException;
+import com.amazon.carbonado.FetchNoneException;
+import com.amazon.carbonado.PersistException;
+import com.amazon.carbonado.PersistNoneException;
+import com.amazon.carbonado.Query;
+import com.amazon.carbonado.Storable;
+
+import com.amazon.carbonado.filter.Filter;
+
+import com.amazon.carbonado.info.OrderedProperty;
+
+import com.amazon.carbonado.util.Appender;
+
+/**
+ * AbstractQuery implements a small set of common Query methods. Subclasses
+ * should consider overriding some of these methods, if it provides better
+ * performance.
+ *
+ * @author Brian S O'Neill
+ */
+public abstract class AbstractQuery<S extends Storable> implements Query<S>, Appender {
+    protected static final String[] EMPTY_ORDERINGS = {};
+
+    protected static String[] extractOrderingNames(OrderedProperty<?>[] orderings) {
+        String[] orderingStrings;
+        if (orderings == null || orderings.length == 0) {
+            return EMPTY_ORDERINGS;
+        }
+        orderingStrings = new String[orderings.length];
+        for (int i=0; i<orderingStrings.length; i++) {
+            orderingStrings[i] = orderings[i].toString().intern();
+        }
+        return orderingStrings;
+    }
+
+    // Note: Since constructor takes no parameters, this class is called
+    // Abstract instead of Base.
+    protected AbstractQuery() {
+    }
+
+    public Query<S> and(String filter) throws FetchException {
+        return and(Filter.filterFor(getStorableType(), filter));
+    }
+
+    public Query<S> or(String filter) throws FetchException {
+        return or(Filter.filterFor(getStorableType(), filter));
+    }
+
+    public S loadOne() throws FetchException {
+        S obj = tryLoadOne();
+        if (obj == null) {
+            throw new FetchNoneException(toString());
+        }
+        return obj;
+    }
+
+    public S tryLoadOne() throws FetchException {
+        Cursor<S> cursor = fetch();
+        try {
+            if (cursor.hasNext()) {
+                S obj = cursor.next();
+                if (cursor.hasNext()) {
+                    throw new FetchMultipleException(toString());
+                }
+                return obj;
+            } else {
+                return null;
+            }
+        } finally {
+            cursor.close();
+        }
+    }
+
+    public void deleteOne() throws PersistException {
+        if (!tryDeleteOne()) {
+            throw new PersistNoneException(toString());
+        }
+    }
+
+    public boolean printNative() {
+        try {
+            return printNative(System.out);
+        } catch (IOException e) {
+            // Shouldn't happen since PrintStream suppresses exceptions.
+            throw new UndeclaredThrowableException(e);
+        }
+    }
+
+    public boolean printNative(Appendable app) throws IOException {
+        return printNative(app, 0);
+    }
+
+    public boolean printPlan() {
+        try {
+            return printPlan(System.out);
+        } catch (IOException e) {
+            // Shouldn't happen since PrintStream suppresses exceptions.
+            throw new UndeclaredThrowableException(e);
+        }
+    }
+
+    public boolean printPlan(Appendable app) throws IOException {
+        return printPlan(app, 0);
+    }
+
+    /**
+     * Implementation calls appendTo.
+     */
+    @Override
+    public String toString() {
+        StringBuilder b = new StringBuilder();
+        try {
+            appendTo(b);
+        } catch (IOException e) {
+            // Not gonna happen
+        }
+        return b.toString();
+    }
+}