Added support for outer joins.

9 files changed, 430 insertions, 71 deletions

diff --git a/RELEASE-NOTES.txt b/RELEASE-NOTES.txt
index 60880db..c844408 100644
--- a/RELEASE-NOTES.txt
+++ b/RELEASE-NOTES.txt
@@ -41,6 +41,7 @@ Carbonado change history
   which resolve to null are cached as before, but non-nullable join properties

   do not cache null.

 - Added support for "where exists" in queries via new syntax.

+- Added support for outer joins via new syntax.

 

 1.1 to 1.1.2

 -------------------------------

diff --git a/src/main/java/com/amazon/carbonado/Storage.java b/src/main/java/com/amazon/carbonado/Storage.java
index 551e1eb..a1cc420 100644
--- a/src/main/java/com/amazon/carbonado/Storage.java
+++ b/src/main/java/com/amazon/carbonado/Storage.java
@@ -90,8 +90,12 @@ public interface Storage<S extends Storable> {
      *                 | "(" Filter ")"

      * PropertyFilter  = ChainedProperty RelOp "?"

      * RelOp           = "=" | "!=" | "&lt;" | "&gt;=" | "&gt;" | "&lt;="

-     * ChainedProperty = Identifier { "." Identifier }

      * ChainedFilter   = ChainedProperty "(" [ Filter ] ")"

+     * ChainedProperty = Identifier

+     *                 | InnerJoin "." ChainedProperty

+     *                 | OuterJoin "." ChainedProperty

+     * InnerJoin       = Identifier

+     * OuterJoin       = '(' Identifier ')'

      * </pre>

      *

      * @param filter query filter expression

diff --git a/src/main/java/com/amazon/carbonado/cursor/FilteredCursorGenerator.java b/src/main/java/com/amazon/carbonado/cursor/FilteredCursorGenerator.java
index 04ea2e8..dba2062 100644
--- a/src/main/java/com/amazon/carbonado/cursor/FilteredCursorGenerator.java
+++ b/src/main/java/com/amazon/carbonado/cursor/FilteredCursorGenerator.java
@@ -464,18 +464,23 @@ class FilteredCursorGenerator {
 

         /**

          * Generated code checks if chained properties resolve to null, and if

-         * so, branches to the current scope's fail location.

+         * so, branches to the current scope's fail or success location.

          */

         private void loadChainedProperty(CodeBuilder b, ChainedProperty<?> chained) {

             b.loadLocal(mStorableVar);

             loadProperty(b, chained.getPrimeProperty());

             for (int i=0; i<chained.getChainCount(); i++) {

-                // Check if last loaded property was null, and fail if so.

+                // Check if last loaded property was null. Fail for inner join,

+                // success for outer join.

                 b.dup();

                 Label notNull = b.createLabel();

                 b.ifNullBranch(notNull, false);

                 b.pop();

-                getScope().fail(b);

+                if (chained.isOuterJoin(i)) {

+                    getScope().success(b);

+                } else {

+                    getScope().fail(b);

+                }

                 notNull.setLocation();

 

                 // Now load next property in chain.

diff --git a/src/main/java/com/amazon/carbonado/filter/Filter.java b/src/main/java/com/amazon/carbonado/filter/Filter.java
index 4f32179..be70ff1 100644
--- a/src/main/java/com/amazon/carbonado/filter/Filter.java
+++ b/src/main/java/com/amazon/carbonado/filter/Filter.java
@@ -55,8 +55,12 @@ import com.amazon.carbonado.util.Appender;
  *                 | "(" Filter ")"

  * PropertyFilter  = ChainedProperty RelOp "?"

  * RelOp           = "=" | "!=" | "&lt;" | "&gt;=" | "&gt;" | "&lt;="

- * ChainedProperty = Identifier { "." Identifier }

  * ChainedFilter   = ChainedProperty "(" [ Filter ] ")"

+ * ChainedProperty = Identifier

+ *                 | InnerJoin "." ChainedProperty

+ *                 | OuterJoin "." ChainedProperty

+ * InnerJoin       = Identifier

+ * OuterJoin       = '(' Identifier ')'

  * </pre>

  *

  * @author Brian S O'Neill

diff --git a/src/main/java/com/amazon/carbonado/filter/FilterParser.java b/src/main/java/com/amazon/carbonado/filter/FilterParser.java
index 5d3762e..ed9cec6 100644
--- a/src/main/java/com/amazon/carbonado/filter/FilterParser.java
+++ b/src/main/java/com/amazon/carbonado/filter/FilterParser.java
@@ -115,7 +115,22 @@ class FilterParser<S extends Storable> {
 

     private Filter<S> parseEntityFilter() {

         int c = nextCharIgnoreWhitespace();

-        if (c == '(') {

+

+        parenFilter: if (c == '(') {

+            // Need to peek ahead to see if this is an outer join.

+            int savedPos = mPos;

+            try {

+                if (Character.isJavaIdentifierStart(nextCharIgnoreWhitespace())) {

+                    mPos--;

+                    parseIdentifier();

+                    if (nextCharIgnoreWhitespace() == ')') {

+                        // Is an outer join, so back up.

+                        break parenFilter;

+                    }

+                }

+            } finally {

+                mPos = savedPos;

+            }

             Filter<S> test = parseFilter();

             c = nextCharIgnoreWhitespace();

             if (c != ')') {

@@ -123,31 +138,31 @@ class FilterParser<S extends Storable> {
                 throw error("Right paren expected");

             }

             return test;

-        } else {

+        }

+

+        mPos--;

+        ChainedProperty<S> chained = parseChainedProperty();

+        c = nextCharIgnoreWhitespace();

+        if (c != '(') {

             mPos--;

-            ChainedProperty<S> chained = parseChainedProperty();

-            c = nextCharIgnoreWhitespace();

-            if (c != '(') {

-                mPos--;

-                return parsePropertyFilter(chained);

-            }

+            return parsePropertyFilter(chained);

+        }

 

-            Filter<?> subFilter;

+        Filter<?> subFilter;

+        c = nextCharIgnoreWhitespace();

+        if (c == ')') {

+            subFilter = null;

+        } else {

+            mPos--;

+            subFilter = parseChainedFilter(chained);

             c = nextCharIgnoreWhitespace();

-            if (c == ')') {

-                subFilter = null;

-            } else {

+            if (c != ')') {

                 mPos--;

-                subFilter = parseChainedFilter(chained);

-                c = nextCharIgnoreWhitespace();

-                if (c != ')') {

-                    mPos--;

-                    throw error("Right paren expected");

-                }

+                throw error("Right paren expected");

             }

-

-            return ExistsFilter.build(chained, subFilter, false);

         }

+

+        return ExistsFilter.build(chained, subFilter, false);

     }

     

     private PropertyFilter<S> parsePropertyFilter(ChainedProperty<S> chained) {

@@ -239,6 +254,18 @@ class FilterParser<S extends Storable> {
 

     @SuppressWarnings("unchecked")

     ChainedProperty<S> parseChainedProperty() {

+        List<Boolean> outerJoinList = null;

+        int lastOuterJoinPos = -1;

+

+        if (nextChar() == '(') {

+            lastOuterJoinPos = mPos - 1;

+            // Skip any whitespace after paren.

+            nextCharIgnoreWhitespace();

+            outerJoinList = new ArrayList<Boolean>(4);

+            outerJoinList.add(true);

+        }

+        mPos--;

+

         String ident = parseIdentifier();

         StorableProperty<S> prime =

             StorableIntrospector.examine(mType).getAllProperties().get(ident);

@@ -248,8 +275,21 @@ class FilterParser<S extends Storable> {
                         mType.getName() + '"');

         }

 

+        if (outerJoinList != null && outerJoinList.get(0)) {

+            if (nextCharIgnoreWhitespace() != ')') {

+                mPos--;

+                throw error("Right paren expected");

+            }

+        }

+

         if (nextCharIgnoreWhitespace() != '.') {

             mPos--;

+            if (outerJoinList != null && outerJoinList.get(0)) {

+                if (lastOuterJoinPos >= 0) {

+                    mPos = lastOuterJoinPos;

+                }

+                throw error("Outer join not allowed for non-chained property");

+            }

             return ChainedProperty.get(prime);

         }

 

@@ -257,7 +297,28 @@ class FilterParser<S extends Storable> {
         Class<?> type = prime.getType();

 

         while (true) {

+            lastOuterJoinPos = -1;

+

+            if (nextChar() == '(') {

+                lastOuterJoinPos = mPos - 1;

+                // Skip any whitespace after paren.

+                nextCharIgnoreWhitespace();

+                if (outerJoinList == null) {

+                    outerJoinList = new ArrayList<Boolean>(4);

+                    // Fill in false values.

+                    outerJoinList.add(false); // prime is inner join

+                    for (int i=chain.size(); --i>=0; ) {

+                        outerJoinList.add(false);

+                    }

+                }

+                outerJoinList.add(true);

+            } else if (outerJoinList != null) {

+                outerJoinList.add(false);

+            }

+            mPos--;

+

             ident = parseIdentifier();

+

             if (Storable.class.isAssignableFrom(type)) {

                 StorableInfo<?> info =

                     StorableIntrospector.examine((Class<? extends Storable>) type);

@@ -274,14 +335,38 @@ class FilterParser<S extends Storable> {
                 throw error("Property \"" + ident + "\" not found for type \"" +

                             type.getName() + "\" because it has no properties");

             }

+

+            if (outerJoinList != null && outerJoinList.get(outerJoinList.size() - 1)) {

+                if (nextCharIgnoreWhitespace() != ')') {

+                    mPos--;

+                    throw error("Right paren expected");

+                }

+            }

+

             if (nextCharIgnoreWhitespace() != '.') {

                 mPos--;

                 break;

             }

         }

 

+        boolean[] outerJoin = null;

+        if (outerJoinList != null) {

+            if (outerJoinList.get(outerJoinList.size() - 1)) {

+                if (lastOuterJoinPos >= 0) {

+                    mPos = lastOuterJoinPos;

+                }

+                throw error("Outer join not allowed for last property in chain");

+            }

+            outerJoin = new boolean[outerJoinList.size()];

+            for (int i=outerJoinList.size(); --i>=0; ) {

+                outerJoin[i] = outerJoinList.get(i);

+            }

+        }

+

         return ChainedProperty

-            .get(prime, (StorableProperty<?>[]) chain.toArray(new StorableProperty[chain.size()]));

+            .get(prime,

+                 (StorableProperty<?>[]) chain.toArray(new StorableProperty[chain.size()]),

+                 outerJoin);

     }

 

     private String parseIdentifier() {

diff --git a/src/main/java/com/amazon/carbonado/filter/PropertyFilter.java b/src/main/java/com/amazon/carbonado/filter/PropertyFilter.java
index c4a585d..c3c5c79 100644
--- a/src/main/java/com/amazon/carbonado/filter/PropertyFilter.java
+++ b/src/main/java/com/amazon/carbonado/filter/PropertyFilter.java
@@ -26,6 +26,7 @@ import org.cojen.classfile.TypeDesc;
 

 import com.amazon.carbonado.Storable;

 import com.amazon.carbonado.info.ChainedProperty;

+import com.amazon.carbonado.info.StorableProperty;

 

 /**

  * Filter tree node that performs a relational test against a specific property

@@ -100,6 +101,10 @@ public class PropertyFilter<S extends Storable> extends Filter<S> {
         if (property == null || op == null) {

             throw new IllegalArgumentException();

         }

+        if (property.isOuterJoin(property.getChainCount())) {

+            throw new IllegalArgumentException

+                ("Last property in chain cannot be an outer join: " + property);

+        }

         mProperty = property;

         mOp = op;

         mBindID = bindID;

@@ -108,10 +113,35 @@ public class PropertyFilter<S extends Storable> extends Filter<S> {
 

     @Override

     public PropertyFilter<S> not() {

+        ChainedProperty<S> property = mProperty;

+

+        if (property.getChainCount() > 0) {

+            // Flip inner/outer joins.

+

+            int chainCount = property.getChainCount();

+            StorableProperty<?>[] chain = new StorableProperty[chainCount];

+            for (int i=0; i<chainCount; i++) {

+                chain[i] = property.getChainedProperty(i);

+            }

+

+            boolean[] outerJoin = null;

+            // Flip all but the last property in the chain.

+            for (int i=0; i<chainCount; i++) {

+                if (!property.isOuterJoin(i)) {

+                    if (outerJoin == null) {

+                        outerJoin = new boolean[chainCount + 1];

+                    }

+                    outerJoin[i] = true;

+                }

+            }

+

+            property = ChainedProperty.get(property.getPrimeProperty(), chain, outerJoin);

+        }

+

         if (mBindID == BOUND_CONSTANT) {

-            return getCanonical(mProperty, mOp.reverse(), mConstant);

+            return getCanonical(property, mOp.reverse(), mConstant);

         } else {

-            return getCanonical(mProperty, mOp.reverse(), mBindID);

+            return getCanonical(property, mOp.reverse(), mBindID);

         }

     }

 

diff --git a/src/main/java/com/amazon/carbonado/info/ChainedProperty.java b/src/main/java/com/amazon/carbonado/info/ChainedProperty.java
index e067350..71f1ba5 100644
--- a/src/main/java/com/amazon/carbonado/info/ChainedProperty.java
+++ b/src/main/java/com/amazon/carbonado/info/ChainedProperty.java
@@ -29,7 +29,7 @@ import com.amazon.carbonado.Storable;
 import com.amazon.carbonado.util.Appender;

 

 /**

- * Represents a property to query against or to order by. Properties may be

+ * Represents a property to filter on or to order by. Properties may be

  * specified in a simple form, like "firstName", or in a chained form, like

  * "address.state". In both forms, the first property is the "prime"

  * property. All properties that follow are chained.

@@ -46,7 +46,7 @@ public class ChainedProperty<S extends Storable> implements Appender {
      */

     @SuppressWarnings("unchecked")

     public static <S extends Storable> ChainedProperty<S> get(StorableProperty<S> prime) {

-        return (ChainedProperty<S>) cCanonical.put(new ChainedProperty<S>(prime, null));

+        return (ChainedProperty<S>) cCanonical.put(new ChainedProperty<S>(prime, null, null));

     }

 

     /**

@@ -58,7 +58,22 @@ public class ChainedProperty<S extends Storable> implements Appender {
     @SuppressWarnings("unchecked")

     public static <S extends Storable> ChainedProperty<S> get(StorableProperty<S> prime,

                                                               StorableProperty<?>... chain) {

-        return (ChainedProperty<S>) cCanonical.put(new ChainedProperty<S>(prime, chain));

+        return (ChainedProperty<S>) cCanonical.put(new ChainedProperty<S>(prime, chain, null));

+    }

+

+    /**

+     * Returns a canonical instance.

+     *

+     * @throws IllegalArgumentException if prime is null or if chained

+     * properties are not formed properly

+     * @since 1.2

+     */

+    @SuppressWarnings("unchecked")

+    public static <S extends Storable> ChainedProperty<S> get(StorableProperty<S> prime,

+                                                              StorableProperty<?>[] chain,

+                                                              boolean[] outerJoin) {

+        return (ChainedProperty<S>) cCanonical.put

+            (new ChainedProperty<S>(prime, chain, outerJoin));

     }

 

     /**

@@ -82,12 +97,20 @@ public class ChainedProperty<S extends Storable> implements Appender {
 

         String name;

         if (dot < 0) {

-            name = str;

+            name = str.trim();

         } else {

-            name = str.substring(pos, dot);

+            name = str.substring(pos, dot).trim();

             pos = dot + 1;

         }

 

+        List<Boolean> outerJoinList = null;

+

+        if (name.startsWith("(") && name.endsWith(")")) {

+            outerJoinList = new ArrayList<Boolean>(4);

+            outerJoinList.add(true);

+            name = name.substring(1, name.length() - 1).trim();

+        }

+

         StorableProperty<S> prime = info.getAllProperties().get(name);

 

         if (prime == null) {

@@ -97,7 +120,11 @@ public class ChainedProperty<S extends Storable> implements Appender {
         }

 

         if (pos <= 0) {

-            return get(prime);

+            if (outerJoinList == null || !outerJoinList.get(0)) {

+                return get(prime);

+            } else {

+                return get(prime, null, new boolean[] {true});

+            }

         }

 

         List<StorableProperty<?>> chain = new ArrayList<StorableProperty<?>>(4);

@@ -106,12 +133,28 @@ public class ChainedProperty<S extends Storable> implements Appender {
         while (pos > 0) {

             dot = str.indexOf('.', pos);

             if (dot < 0) {

-                name = str.substring(pos);

+                name = str.substring(pos).trim();

                 pos = -1;

             } else {

-                name = str.substring(pos, dot);

+                name = str.substring(pos, dot).trim();

                 pos = dot + 1;

             }

+

+            if (name.startsWith("(") && name.endsWith(")")) {

+                if (outerJoinList == null) {

+                    outerJoinList = new ArrayList<Boolean>(4);

+                    // Fill in false values.

+                    outerJoinList.add(false); // prime is inner join

+                    for (int i=chain.size(); --i>=0; ) {

+                        outerJoinList.add(false);

+                    }

+                }

+                outerJoinList.add(true);

+                name = name.substring(1, name.length() - 1).trim();

+            } else if (outerJoinList != null) {

+                outerJoinList.add(false);

+            }

+

             if (Storable.class.isAssignableFrom(type)) {

                 StorableInfo propInfo =

                     StorableIntrospector.examine((Class<? extends Storable>) type);

@@ -131,24 +174,51 @@ public class ChainedProperty<S extends Storable> implements Appender {
             }

         }

 

+        boolean[] outerJoin = null;

+        if (outerJoinList != null) {

+            outerJoin = new boolean[outerJoinList.size()];

+            for (int i=outerJoinList.size(); --i>=0; ) {

+                outerJoin[i] = outerJoinList.get(i);

+            }

+        }

+

         return get(prime,

-                   (StorableProperty<?>[]) chain.toArray(new StorableProperty[chain.size()]));

+                   (StorableProperty<?>[]) chain.toArray(new StorableProperty[chain.size()]),

+                   outerJoin);

     }

 

     private final StorableProperty<S> mPrime;

     private final StorableProperty<?>[] mChain;

+    private final boolean[] mOuterJoin;

 

     /**

      * @param prime must not be null

      * @param chain can be null if none

-     * @throws IllegalArgumentException if prime is null

+     * @param outerJoin can be null for all inner joins

+     * @throws IllegalArgumentException if prime is null or if outer join chain is too long

      */

-    private ChainedProperty(StorableProperty<S> prime, StorableProperty<?>[] chain) {

+    private ChainedProperty(StorableProperty<S> prime, StorableProperty<?>[] chain,

+                            boolean[] outerJoin)

+    {

         if (prime == null) {

-            throw new IllegalArgumentException();

+            throw new IllegalArgumentException("No prime property");

         }

+

         mPrime = prime;

         mChain = (chain == null || chain.length == 0) ? null : chain.clone();

+

+        if (outerJoin != null) {

+            int expectedLength = (chain == null ? 0 : chain.length) + 1;

+            if (outerJoin.length > expectedLength) {

+                throw new IllegalArgumentException

+                    ("Outer join array too long: " + outerJoin.length + " > " + expectedLength);

+            }

+            boolean[] newOuterJoin = new boolean[expectedLength];

+            System.arraycopy(outerJoin, 0, newOuterJoin, 0, outerJoin.length);

+            outerJoin = newOuterJoin;

+        }

+

+        mOuterJoin = outerJoin;

     }

 

     public StorableProperty<S> getPrimeProperty() {

@@ -219,6 +289,9 @@ public class ChainedProperty<S extends Storable> implements Appender {
         return mChain == null ? 0 : mChain.length;

     }

 

+    /**

+     * @param index valid range is 0 to chainCount - 1

+     */

     public StorableProperty<?> getChainedProperty(int index) throws IndexOutOfBoundsException {

         if (mChain == null) {

             throw new IndexOutOfBoundsException();

@@ -228,24 +301,73 @@ public class ChainedProperty<S extends Storable> implements Appender {
     }

 

     /**

+     * Returns true if the property at the given index should be treated as an

+     * outer join. Index zero is the prime property.

+     *

+     * @param index valid range is 0 to chainCount

+     * @since 1.2

+     */

+    public boolean isOuterJoin(int index) throws IndexOutOfBoundsException {

+        if (index < 0) {

+            throw new IndexOutOfBoundsException();

+        }

+        if (mOuterJoin == null) {

+            if (index > getChainCount()) {

+                throw new IndexOutOfBoundsException();

+            }

+            return false;

+        }

+        return mOuterJoin[index];

+    }

+

+    /**

      * Returns a new ChainedProperty with another property appended.

      */

     public ChainedProperty<S> append(StorableProperty<?> property) {

+        return append(property, false);

+    }

+

+    /**

+     * Returns a new ChainedProperty with another property appended.

+     *

+     * @param outerJoin pass true for outer join

+     * @since 1.2

+     */

+    public ChainedProperty<S> append(StorableProperty<?> property, boolean outerJoin) {

+        if (property == null) {

+            throw new IllegalArgumentException();

+        }

+

         StorableProperty<?>[] newChain = new StorableProperty[getChainCount() + 1];

         if (newChain.length > 1) {

             System.arraycopy(mChain, 0, newChain, 0, mChain.length);

         }

         newChain[newChain.length - 1] = property;

-        return get(mPrime, newChain);

+

+        boolean[] newOuterJoin = mOuterJoin;

+

+        if (outerJoin) {

+            newOuterJoin = new boolean[newChain.length + 1];

+            if (mOuterJoin != null) {

+                System.arraycopy(mOuterJoin, 0, newOuterJoin, 0, mOuterJoin.length);

+            }

+            newOuterJoin[newOuterJoin.length - 1] = true;

+        }

+

+        return get(mPrime, newChain, newOuterJoin);

     }

 

     /**

      * Returns a new ChainedProperty with another property appended.

      */

     public ChainedProperty<S> append(ChainedProperty<?> property) {

+        if (property == null) {

+            throw new IllegalArgumentException();

+        }

+

         final int propChainCount = property.getChainCount();

         if (propChainCount == 0) {

-            return append(property.getPrimeProperty());

+            return append(property.getPrimeProperty(), property.isOuterJoin(0));

         }

 

         StorableProperty<?>[] newChain =

@@ -262,7 +384,19 @@ public class ChainedProperty<S extends Storable> implements Appender {
             newChain[pos++] = property.getChainedProperty(i);

         }

 

-        return get(mPrime, newChain);

+        boolean[] newOuterJoin = mOuterJoin;

+

+        if (property.mOuterJoin != null) {

+            newOuterJoin = new boolean[newChain.length + 1];

+            if (mOuterJoin != null) {

+                System.arraycopy(mOuterJoin, 0, newOuterJoin, 0, mOuterJoin.length);

+            }

+            System.arraycopy(property.mOuterJoin, 0,

+                             newOuterJoin, mOuterJoin.length,

+                             property.mOuterJoin.length);

+        }

+

+        return get(mPrime, newChain, newOuterJoin);

     }

 

     /**

@@ -275,11 +409,23 @@ public class ChainedProperty<S extends Storable> implements Appender {
             throw new IllegalStateException();

         }

         if (getChainCount() == 1) {

-            return get(mPrime);

+            if (!isOuterJoin(0)) {

+                return get(mPrime);

+            } else {

+                return get(mPrime, null, new boolean[] {true});

+            }

         }

         StorableProperty<?>[] newChain = new StorableProperty[getChainCount() - 1];

         System.arraycopy(mChain, 0, newChain, 0, newChain.length);

-        return get(mPrime, newChain);

+

+        boolean[] newOuterJoin = mOuterJoin;

+

+        if (newOuterJoin != null && newOuterJoin.length > (newChain.length + 1)) {

+            newOuterJoin = new boolean[newChain.length + 1];

+            System.arraycopy(mOuterJoin, 0, newOuterJoin, 0, newChain.length + 1);

+        }

+

+        return get(mPrime, newChain, newOuterJoin);

     }

 

     /**

@@ -293,11 +439,23 @@ public class ChainedProperty<S extends Storable> implements Appender {
             throw new IllegalStateException();

         }

         if (getChainCount() == 1) {

-            return get(mChain[0]);

+            if (!isOuterJoin(1)) {

+                return get(mChain[0]);

+            } else {

+                return get(mChain[0], null, new boolean[] {true});

+            }

         }

         StorableProperty<?>[] newChain = new StorableProperty[getChainCount() - 1];

         System.arraycopy(mChain, 1, newChain, 0, newChain.length);

-        return get(mChain[0], newChain);

+

+        boolean[] newOuterJoin = mOuterJoin;

+

+        if (newOuterJoin != null) {

+            newOuterJoin = new boolean[newChain.length + 1];

+            System.arraycopy(mOuterJoin, 1, newOuterJoin, 0, mOuterJoin.length - 1);

+        }

+

+        return get(mChain[0], newChain, newOuterJoin);

     }

 

     @Override

@@ -309,6 +467,14 @@ public class ChainedProperty<S extends Storable> implements Appender {
                 hash = hash * 31 + chain[i].hashCode();

             }

         }

+        boolean[] outerJoin = mOuterJoin;

+        if (outerJoin != null) {

+            for (int i=outerJoin.length; --i>=0; ) {

+                if (outerJoin[i]) {

+                    hash += 1;

+                }

+            }

+        }

         return hash;

     }

 

@@ -324,8 +490,18 @@ public class ChainedProperty<S extends Storable> implements Appender {
             // equals method. Otherwise, canonical ChainedProperty instances

             // may refer to StorableProperty instances which are no longer

             // available through the Introspector.

-            return getType() == other.getType() && mPrime == other.mPrime

-                && identityEquals(mChain, other.mChain);

+            if (getType() == other.getType() && mPrime == other.mPrime

+                && identityEquals(mChain, other.mChain))

+            {

+                // Compare outer joins.

+                int count = getChainCount() + 1;

+                for (int i=0; i<count; i++) {

+                    if (isOuterJoin(i) != other.isOuterJoin(i)) {

+                        return false;

+                    }

+                }

+                return true;

+            }

         }

         return false;

     }

@@ -362,7 +538,7 @@ public class ChainedProperty<S extends Storable> implements Appender {
      */

     @Override

     public String toString() {

-        if (mChain == null) {

+        if (mChain == null && !isOuterJoin(0)) {

             return mPrime.getName();

         }

         StringBuilder buf = new StringBuilder();

@@ -380,7 +556,7 @@ public class ChainedProperty<S extends Storable> implements Appender {
      * many-to-one joins.

      */

     public void appendTo(Appendable app) throws IOException {

-        app.append(mPrime.getName());

+        appendPropTo(app, mPrime.getName(), isOuterJoin(0));

         StorableProperty<?>[] chain = mChain;

         if (chain != null) {

             app.append('.');

@@ -388,8 +564,18 @@ public class ChainedProperty<S extends Storable> implements Appender {
                 if (i > 0) {

                     app.append('.');

                 }

-                app.append(chain[i].getName());

+                appendPropTo(app, chain[i].getName(), isOuterJoin(i + 1));

             }

         }

     }

+

+    private void appendPropTo(Appendable app, String name, boolean outer) throws IOException {

+        if (outer) {

+            app.append('(');

+        }

+        app.append(name);

+        if (outer) {

+            app.append(')');

+        }

+    }

 }

diff --git a/src/main/java/com/amazon/carbonado/qe/IndexedQueryAnalyzer.java b/src/main/java/com/amazon/carbonado/qe/IndexedQueryAnalyzer.java
index 60cf3da..93d4666 100644
--- a/src/main/java/com/amazon/carbonado/qe/IndexedQueryAnalyzer.java
+++ b/src/main/java/com/amazon/carbonado/qe/IndexedQueryAnalyzer.java
@@ -209,12 +209,20 @@ public class IndexedQueryAnalyzer<S extends Storable> {
             if (!isProperJoin(chainedProp.getPrimeProperty())) {

                 break evaluate;

             }

+            if (chainedProp.isOuterJoin(0)) {

+                // Outer joins cannot be optimized via foreign indexes.

+                break evaluate;

+            }

 

             int count = chainedProp.getChainCount();

             for (int i=0; i<count; i++) {

                 if (!isProperJoin(chainedProp.getChainedProperty(i))) {

                     break evaluate;

                 }

+                if (chainedProp.isOuterJoin(i + 1)) {

+                    // Outer joins cannot be optimized via foreign indexes.

+                    break evaluate;

+                }

             }

 

             // All foreign indexes are available for use.

diff --git a/src/main/java/com/amazon/carbonado/repo/jdbc/JDBCStorage.java b/src/main/java/com/amazon/carbonado/repo/jdbc/JDBCStorage.java
index 855cce4..2a1212a 100644
--- a/src/main/java/com/amazon/carbonado/repo/jdbc/JDBCStorage.java
+++ b/src/main/java/com/amazon/carbonado/repo/jdbc/JDBCStorage.java
@@ -846,11 +846,45 @@ class JDBCStorage<S extends Storable> extends StandardQueryFactory<S>
     private static class JoinNode {

         // Joined property which led to this node. For root node, it is null.

         private final JDBCStorableProperty<?> mProperty;

+        private final boolean mOuterJoin;

 

         private final JDBCStorableInfo<?> mInfo;

         private final String mAlias;

 

-        private final Map<String, JoinNode> mSubNodes;

+        private static class SubNodeKey {

+            final String mPropertyName;

+            final boolean mOuterJoin;

+

+            SubNodeKey(String propertyName, boolean outerJoin) {

+                mPropertyName = propertyName;

+                mOuterJoin = outerJoin;

+            }

+

+            @Override

+            public int hashCode() {

+                return mPropertyName.hashCode();

+            }

+

+            @Override

+            public boolean equals(Object obj) {

+                if (this == obj) {

+                    return true;

+                }

+                if (obj instanceof SubNodeKey) {

+                    SubNodeKey other = (SubNodeKey) obj;

+                    return mPropertyName.equals(other.mPropertyName)

+                        && mOuterJoin == other.mOuterJoin;

+                }

+                return false;

+            }

+

+            @Override

+            public String toString() {

+                return "propertyName=" + mPropertyName + ", outerJoin=" + mOuterJoin;

+            }

+        }

+

+        private final Map<SubNodeKey, JoinNode> mSubNodes;

 

         private boolean mAliasRequired;

 

@@ -858,15 +892,19 @@ class JDBCStorage<S extends Storable> extends StandardQueryFactory<S>
          * @param alias table alias in SQL statement, i.e. "T1"

          */

         JoinNode(JDBCStorableInfo<?> info, String alias) {

-            this(null, info, alias);

+            this(null, false, info, alias);

         }

 

-        private JoinNode(JDBCStorableProperty<?> property, JDBCStorableInfo<?> info, String alias)

+        private JoinNode(JDBCStorableProperty<?> property,

+                         boolean outerJoin,

+                         JDBCStorableInfo<?> info,

+                         String alias)

         {

             mProperty = property;

+            mOuterJoin = outerJoin;

             mInfo = info;

             mAlias = alias;

-            mSubNodes = new LinkedHashMap<String, JoinNode>();

+            mSubNodes = new LinkedHashMap<SubNodeKey, JoinNode>();

         }

 

         /**

@@ -891,8 +929,9 @@ class JDBCStorage<S extends Storable> extends StandardQueryFactory<S>
             } else {

                 property = chained.getChainedProperty(offset - 1);

             }

-            String name = property.getName();

-            JoinNode subNode = mSubNodes.get(name);

+            boolean outerJoin = chained.isOuterJoin(offset);

+            SubNodeKey key = new SubNodeKey(property.getName(), outerJoin); 

+            JoinNode subNode = mSubNodes.get(key);

             if (subNode != null) {

                 return subNode.findAliasFor(chained, offset + 1);

             }

@@ -931,15 +970,11 @@ class JDBCStorage<S extends Storable> extends StandardQueryFactory<S>
 

         private void appendTailJoinTo(StatementBuilder fromClause) {

             for (JoinNode jn : mSubNodes.values()) {

-                // TODO: By default, joins are all inner. A join could become

-                // LEFT OUTER JOIN if the query filter has a term like this:

-                // "address = ? | address.state = ?", and the runtime value of

-                // address is null. Because of DNF transformation and lack of

-                // short-circuit ops, this syntax might be difficult to parse.

-                // This might be a better way of expressing an outer join:

-                // "address(.)state = ?".

-

-                fromClause.append(" INNER JOIN");

+                if (jn.mOuterJoin) {

+                    fromClause.append(" LEFT OUTER JOIN");

+                } else {

+                    fromClause.append(" INNER JOIN");

+                }

                 jn.appendTableNameAndAliasTo(fromClause);

                 fromClause.append(" ON ");

                 int count = jn.mProperty.getJoinElementCount();

@@ -984,13 +1019,14 @@ class JDBCStorage<S extends Storable> extends StandardQueryFactory<S>
             } else {

                 property = chained.getChainedProperty(offset - 1);

             }

-            String name = property.getName();

-            JoinNode subNode = mSubNodes.get(name);

+            boolean outerJoin = chained.isOuterJoin(offset);

+            SubNodeKey key = new SubNodeKey(property.getName(), outerJoin); 

+            JoinNode subNode = mSubNodes.get(key);

             if (subNode == null) {

                 JDBCStorableInfo<?> info = repository.examineStorable(property.getJoinedType());

                 JDBCStorableProperty<?> jProperty = repository.getJDBCStorableProperty(property);

-                subNode = new JoinNode(jProperty, info, aliasGenerator.nextAlias());

-                mSubNodes.put(name, subNode);

+                subNode = new JoinNode(jProperty, outerJoin, info, aliasGenerator.nextAlias());

+                mSubNodes.put(key, subNode);

             }

             subNode.addJoin(repository, chained, aliasGenerator, offset + 1);

         }