Roll everything on up to Tuple5. We boil the plates so that you don't have to!

src/main/java/com/samskivert/depot/QueryBuilder.java

@@ -29,8 +29,9 @@ import com.google.common.collect.Lists;
 import com.samskivert.depot.clause.*;
 import com.samskivert.depot.expression.ColumnExp;
 import com.samskivert.depot.expression.SQLExpression;
-import com.samskivert.depot.impl.Projector;
 import com.samskivert.depot.impl.FindAllQuery;
+import com.samskivert.depot.impl.Projector;
+import com.samskivert.depot.util.*; // TupleN
 
 import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.common.base.Preconditions.checkState;
@@ -378,6 +379,35 @@ public class QueryBuilder<T extends PersistentRecord>
         return select(exp1, exp2).get(0); // TODO: revamp FindOneQuery and use that
     }
 
+    /**
+     * Returns the value from the first row that matches the configured query clauses.
+     */
+    public <V1, V2, V3> Tuple3<V1, V2, V3> load (
+        SQLExpression<V1> exp1, SQLExpression<V2> exp2, SQLExpression<V3> exp3)
+    {
+        return select(exp1, exp2, exp3).get(0); // TODO: revamp FindOneQuery and use that
+    }
+
+    /**
+     * Returns the value from the first row that matches the configured query clauses.
+     */
+    public <V1, V2, V3, V4> Tuple4<V1, V2, V3, V4> load (
+        SQLExpression<V1> exp1, SQLExpression<V2> exp2,
+        SQLExpression<V3> exp3, SQLExpression<V4> exp4)
+    {
+        return select(exp1, exp2, exp3, exp4).get(0); // TODO: revamp FindOneQuery and use that
+    }
+
+    /**
+     * Returns the value from the first row that matches the configured query clauses.
+     */
+    public <V1, V2, V3, V4, V5> Tuple5<V1, V2, V3, V4, V5> load (
+        SQLExpression<V1> exp1, SQLExpression<V2> exp2, SQLExpression<V3> exp3,
+        SQLExpression<V4> exp4, SQLExpression<V5> exp5)
+    {
+        return select(exp1, exp2, exp3, exp4, exp5).get(0); // TODO: use revamped FindOneQuery
+    }
+
     /**
      * Returns just the supplied expression from the rows matching the query.
      */
@@ -396,6 +426,40 @@ public class QueryBuilder<T extends PersistentRecord>
                                _ctx, Projector.create(_pclass, exp1, exp2), getClauses()));
     }
 
+    /**
+     * Returns just the supplied expressions from the rows matching the query.
+     */
+    public <V1, V2, V3> List<Tuple3<V1,V2,V3>> select (
+        SQLExpression<V1> exp1, SQLExpression<V2> exp2, SQLExpression<V3> exp3)
+    {
+        return _ctx.invoke(new FindAllQuery.Projection<T,Tuple3<V1,V2,V3>>(
+                               _ctx, Projector.create(_pclass, exp1, exp2, exp3), getClauses()));
+    }
+
+    /**
+     * Returns just the supplied expressions from the rows matching the query.
+     */
+    public <V1, V2, V3, V4> List<Tuple4<V1,V2,V3,V4>> select (
+        SQLExpression<V1> exp1, SQLExpression<V2> exp2,
+        SQLExpression<V3> exp3, SQLExpression<V4> exp4)
+    {
+        return _ctx.invoke(new FindAllQuery.Projection<T,Tuple4<V1,V2,V3,V4>>(
+                               _ctx, Projector.create(_pclass, exp1, exp2, exp3, exp4),
+                               getClauses()));
+    }
+
+    /**
+     * Returns just the supplied expressions from the rows matching the query.
+     */
+    public <V1, V2, V3, V4, V5> List<Tuple5<V1,V2,V3,V4,V5>> select (
+        SQLExpression<V1> exp1, SQLExpression<V2> exp2, SQLExpression<V3> exp3,
+        SQLExpression<V4> exp4, SQLExpression<V5> exp5)
+    {
+        return _ctx.invoke(new FindAllQuery.Projection<T,Tuple5<V1,V2,V3,V4,V5>>(
+                               _ctx, Projector.create(_pclass, exp1, exp2, exp3, exp4, exp5),
+                               getClauses()));
+    }
+
     /**
      * Deletes the records that match the configured query clauses. Note that only the where
      * clauses are used to evaluate a deletion. Attempts to use other clauses will result in

src/main/java/com/samskivert/depot/impl/Projector.java

@@ -21,8 +21,8 @@
 package com.samskivert.depot.impl;
 
 import com.samskivert.depot.PersistentRecord;
-import com.samskivert.depot.Tuple2;
 import com.samskivert.depot.expression.SQLExpression;
+import com.samskivert.depot.util.*; // TupleN
 
 /**
  * Contains a set of selection expressions which are to be projected (selected) from a set of
@@ -53,6 +53,54 @@ public abstract class Projector<T extends PersistentRecord,R>
         };
     }
 
+    public static <T extends PersistentRecord, V1, V2, V3> Projector<T,Tuple3<V1,V2,V3>> create (
+        Class<T> ptype, SQLExpression<V1> col1, SQLExpression<V2> col2, SQLExpression<V3> col3)
+    {
+        return new Projector<T, Tuple3<V1,V2,V3>>(ptype, new SQLExpression[] { col1, col2, col3 }) {
+            public Tuple3<V1,V2,V3> createObject (Object[] results) {
+                @SuppressWarnings("unchecked") V1 r1 = (V1)results[0];
+                @SuppressWarnings("unchecked") V2 r2 = (V2)results[1];
+                @SuppressWarnings("unchecked") V3 r3 = (V3)results[2];
+                return new Tuple3<V1,V2,V3>(r1, r2, r3);
+            }
+        };
+    }
+
+    public static <T extends PersistentRecord, V1, V2, V3, V4>
+        Projector<T,Tuple4<V1,V2,V3,V4>> create (
+            Class<T> ptype, SQLExpression<V1> col1, SQLExpression<V2> col2, SQLExpression<V3> col3,
+            SQLExpression<V4> col4)
+    {
+        return new Projector<T, Tuple4<V1,V2,V3,V4>>(
+            ptype, new SQLExpression[] { col1, col2, col3, col4 }) {
+            public Tuple4<V1,V2,V3,V4> createObject (Object[] results) {
+                @SuppressWarnings("unchecked") V1 r1 = (V1)results[0];
+                @SuppressWarnings("unchecked") V2 r2 = (V2)results[1];
+                @SuppressWarnings("unchecked") V3 r3 = (V3)results[2];
+                @SuppressWarnings("unchecked") V4 r4 = (V4)results[3];
+                return new Tuple4<V1,V2,V3,V4>(r1, r2, r3, r4);
+            }
+        };
+    }
+
+    public static <T extends PersistentRecord, V1, V2, V3, V4, V5>
+        Projector<T,Tuple5<V1,V2,V3,V4,V5>> create (
+            Class<T> ptype, SQLExpression<V1> col1, SQLExpression<V2> col2, SQLExpression<V3> col3,
+            SQLExpression<V4> col4, SQLExpression<V5> col5)
+    {
+        return new Projector<T, Tuple5<V1,V2,V3,V4,V5>>(
+            ptype, new SQLExpression[] { col1, col2, col3, col4, col5 }) {
+            public Tuple5<V1,V2,V3,V4,V5> createObject (Object[] results) {
+                @SuppressWarnings("unchecked") V1 r1 = (V1)results[0];
+                @SuppressWarnings("unchecked") V2 r2 = (V2)results[1];
+                @SuppressWarnings("unchecked") V3 r3 = (V3)results[2];
+                @SuppressWarnings("unchecked") V4 r4 = (V4)results[3];
+                @SuppressWarnings("unchecked") V5 r5 = (V5)results[4];
+                return new Tuple5<V1,V2,V3,V4,V5>(r1, r2, r3, r4, r5);
+            }
+        };
+    }
+
     public final Class<T> ptype;
     public final SQLExpression<?>[] selexps;
 

src/main/java/com/samskivert/depot/util/Tuple2.java

@@ -18,7 +18,7 @@
 // License along with this library; if not, write to the Free Software
 // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 
-package com.samskivert.depot;
+package com.samskivert.depot.util;
 
 import java.io.Serializable;
 

src/main/java/com/samskivert/depot/util/Tuple3.java

@@ -0,0 +1,79 @@
+//
+// $Id$
+//
+// Depot library - a Java relational persistence library
+// Copyright (C) 2006-2010 Michael Bayne and Pär Winzell
+//
+// This library is free software; you can redistribute it and/or modify it
+// under the terms of the GNU Lesser General Public License as published
+// by the Free Software Foundation; either version 2.1 of the License, or
+// (at your option) any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public
+// License along with this library; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+
+package com.samskivert.depot.util;
+
+import java.io.Serializable;
+
+import com.google.common.base.Objects;
+
+/**
+ * Contains a three column result. This class is immutable and the objects it references are also
+ * meant to be immutable. They will generally contain only Depot primitive types (Java primitives,
+ * SQL primitives and some array types), which should be treated as immutable.
+ */
+public class Tuple3<A,B,C> implements Serializable
+{
+    /** The first column of the result. */
+    public final A a;
+
+    /** The second column of the result. */
+    public final B b;
+
+    /** The third column of the result. */
+    public final C c;
+
+    /** Constructs an initialized tuple. */
+    public static <A, B, C> Tuple3<A, B, C> create (A a, B b, C c)
+    {
+        return new Tuple3<A, B, C>(a, b, c);
+    }
+
+    /** Constructs an initialized tuple. */
+    public Tuple3 (A a, B b, C c)
+    {
+        this.a = a;
+        this.b = b;
+        this.c = c;
+    }
+
+    @Override
+    public String toString ()
+    {
+        return "[" + a + "," + b + "," + c + "]";
+    }
+
+    @Override
+    public int hashCode ()
+    {
+        return Objects.hashCode(a, b, c);
+    }
+
+    @Override
+    public boolean equals (Object other)
+    {
+        if (other instanceof Tuple3<?,?,?>) {
+            Tuple3<?,?,?> otup = (Tuple3<?,?,?>)other;
+            return Objects.equal(a, otup.a) && Objects.equal(b, otup.b) && Objects.equal(c, otup.c);
+        } else {
+            return false;
+        }
+    }
+}

src/main/java/com/samskivert/depot/util/Tuple4.java

@@ -0,0 +1,84 @@
+//
+// $Id$
+//
+// Depot library - a Java relational persistence library
+// Copyright (C) 2006-2010 Michael Bayne and Pär Winzell
+//
+// This library is free software; you can redistribute it and/or modify it
+// under the terms of the GNU Lesser General Public License as published
+// by the Free Software Foundation; either version 2.1 of the License, or
+// (at your option) any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public
+// License along with this library; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+
+package com.samskivert.depot.util;
+
+import java.io.Serializable;
+
+import com.google.common.base.Objects;
+
+/**
+ * Contains a four column result. This class is immutable and the objects it references are also
+ * meant to be immutable. They will generally contain only Depot primitive types (Java primitives,
+ * SQL primitives and some array types), which should be treated as immutable.
+ */
+public class Tuple4<A,B,C,D> implements Serializable
+{
+    /** The first column of the result. */
+    public final A a;
+
+    /** The second column of the result. */
+    public final B b;
+
+    /** The third column of the result. */
+    public final C c;
+
+    /** The fourth column of the result. */
+    public final D d;
+
+    /** Constructs an initialized tuple. */
+    public static <A, B, C, D> Tuple4<A, B, C, D> create (A a, B b, C c, D d)
+    {
+        return new Tuple4<A, B, C, D>(a, b, c, d);
+    }
+
+    /** Constructs an initialized tuple. */
+    public Tuple4 (A a, B b, C c, D d)
+    {
+        this.a = a;
+        this.b = b;
+        this.c = c;
+        this.d = d;
+    }
+
+    @Override
+    public String toString ()
+    {
+        return "[" + a + "," + b + "," + c + "," + d + "]";
+    }
+
+    @Override
+    public int hashCode ()
+    {
+        return Objects.hashCode(a, b, c, d);
+    }
+
+    @Override
+    public boolean equals (Object other)
+    {
+        if (other instanceof Tuple4<?,?,?,?>) {
+            Tuple4<?,?,?,?> otup = (Tuple4<?,?,?,?>)other;
+            return Objects.equal(a, otup.a) && Objects.equal(b, otup.b) &&
+                Objects.equal(c, otup.c) && Objects.equal(d, otup.d);
+        } else {
+            return false;
+        }
+    }
+}

src/main/java/com/samskivert/depot/util/Tuple5.java

@@ -0,0 +1,88 @@
+//
+// $Id$
+//
+// Depot library - a Java relational persistence library
+// Copyright (C) 2006-2010 Michael Bayne and Pär Winzell
+//
+// This library is free software; you can redistribute it and/or modify it
+// under the terms of the GNU Lesser General Public License as published
+// by the Free Software Foundation; either version 2.1 of the License, or
+// (at your option) any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public
+// License along with this library; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+
+package com.samskivert.depot.util;
+
+import java.io.Serializable;
+
+import com.google.common.base.Objects;
+
+/**
+ * Contains a five column result. This class is immutable and the objects it references are also
+ * meant to be immutable. They will generally contain only Depot primitive types (Java primitives,
+ * SQL primitives and some array types), which should be treated as immutable.
+ */
+public class Tuple5<A,B,C,D,E> implements Serializable
+{
+    /** The first column of the result. */
+    public final A a;
+
+    /** The second column of the result. */
+    public final B b;
+
+    /** The third column of the result. */
+    public final C c;
+
+    /** The fourth column of the result. */
+    public final D d;
+
+    /** The fifth column of the result. */
+    public final E e;
+
+    /** Constructs an initialized tuple. */
+    public static <A, B, C, D, E> Tuple5<A, B, C, D, E> create (A a, B b, C c, D d, E e)
+    {
+        return new Tuple5<A, B, C, D, E>(a, b, c, d, e);
+    }
+
+    /** Constructs an initialized tuple. */
+    public Tuple5 (A a, B b, C c, D d, E e)
+    {
+        this.a = a;
+        this.b = b;
+        this.c = c;
+        this.d = d;
+        this.e = e;
+    }
+
+    @Override
+    public String toString ()
+    {
+        return "[" + a + "," + b + "," + c + "," + d + "," + e + "]";
+    }
+
+    @Override
+    public int hashCode ()
+    {
+        return Objects.hashCode(a, b, c, d, e);
+    }
+
+    @Override
+    public boolean equals (Object other)
+    {
+        if (other instanceof Tuple5<?,?,?,?,?>) {
+            Tuple5<?,?,?,?,?> otup = (Tuple5<?,?,?,?,?>)other;
+            return Objects.equal(a, otup.a) && Objects.equal(b, otup.b) &&
+                Objects.equal(c, otup.c) && Objects.equal(d, otup.d) && Objects.equal(e, otup.e);
+        } else {
+            return false;
+        }
+    }
+}

src/test/java/com/samskivert/depot/ProjectionTest.java

@@ -23,7 +23,7 @@ package com.samskivert.depot;
 import java.util.List;
 
 import com.google.common.collect.Lists;
-import com.samskivert.depot.Tuple2;
+import com.samskivert.depot.util.*; // TupleN
 
 import org.junit.After;
 import org.junit.Before;
@@ -31,9 +31,9 @@ import org.junit.Test;
 import static org.junit.Assert.*;
 
 /**
- * Tests individual field selection.
+ * Tests projection selections, aggregates, etc.
  */
-public class SelectFieldsTest extends TestBase
+public class ProjectionTest extends TestBase
 {
     @Before public void createRecords ()
     {
@@ -70,6 +70,24 @@ public class SelectFieldsTest extends TestBase
         assertEquals(data, want);
     }
 
+    @Test public void testTupleN ()
+    {
+        assertEquals(Tuple2.create(1, "Elvis"),
+                     _repo.from(TestRecord.class).where(TestRecord.RECORD_ID.eq(1)).
+                     load(TestRecord.RECORD_ID, TestRecord.NAME));
+        assertEquals(Tuple3.create(1, "Elvis", 99),
+                     _repo.from(TestRecord.class).where(TestRecord.RECORD_ID.eq(1)).
+                     load(TestRecord.RECORD_ID, TestRecord.NAME, TestRecord.AGE));
+        assertEquals(Tuple4.create(1, "Elvis", 99, "Right here"),
+                     _repo.from(TestRecord.class).where(TestRecord.RECORD_ID.eq(1)).
+                     load(TestRecord.RECORD_ID, TestRecord.NAME, TestRecord.AGE,
+                          TestRecord.HOME_TOWN));
+        assertEquals(Tuple5.create(1, "Elvis", 99, "Right here", EnumKeyRecord.Type.A),
+                     _repo.from(TestRecord.class).where(TestRecord.RECORD_ID.eq(1)).
+                     load(TestRecord.RECORD_ID, TestRecord.NAME, TestRecord.AGE,
+                          TestRecord.HOME_TOWN, TestRecord.TYPE));
+    }
+
     @Test public void testProjectedJoin ()
     {
         // test a basic join

src/test/java/com/samskivert/depot/TestBase.java

@@ -75,6 +75,7 @@ public abstract class TestBase
         rec.age = 99;
         rec.created = now;
         rec.homeTown = "Right here";
+        rec.type = EnumKeyRecord.Type.A;
         rec.lastModified = tnow;
         rec.numbers = new int[] { 9, 0, 2, 1, 0 };
         return rec;
@@ -90,6 +91,7 @@ public abstract class TestBase
         assertEquals(expect.age, got.age);
         assertEquals(expect.created, got.created);
         assertEquals(expect.homeTown, got.homeTown);
+        assertEquals(expect.type, got.type);
         assertEquals(expect.lastModified, got.lastModified);
         assertTrue(Arrays.equals(expect.numbers, got.numbers));
     }

src/test/java/com/samskivert/depot/TestRecord.java

@@ -42,6 +42,7 @@ public class TestRecord extends PersistentRecord
     public static final ColumnExp<String> NAME = colexp(_R, "name");
     public static final ColumnExp<Integer> AGE = colexp(_R, "age");
     public static final ColumnExp<String> HOME_TOWN = colexp(_R, "homeTown");
+    public static final ColumnExp<EnumKeyRecord.Type> TYPE = colexp(_R, "type");
     public static final ColumnExp<Date> CREATED = colexp(_R, "created");
     public static final ColumnExp<Timestamp> LAST_MODIFIED = colexp(_R, "lastModified");
     public static final ColumnExp<int[]> NUMBERS = colexp(_R, "numbers");
@@ -58,6 +59,8 @@ public class TestRecord extends PersistentRecord
 
     public String homeTown;
 
+    public EnumKeyRecord.Type type;
+
     @Index
     public Date created;