Generalize the automatic key value generation code so that it works on any column, and on any number of columns within a record.

src/java/com/samskivert/jdbc/depot/BindVisitor.java

@@ -22,6 +22,7 @@ package com.samskivert.jdbc.depot;
 
 import java.sql.PreparedStatement;
 import java.util.Map;
+import java.util.Set;
 
 import com.samskivert.jdbc.depot.Key.WhereCondition;
 import com.samskivert.jdbc.depot.clause.DeleteClause;
@@ -240,9 +241,9 @@ public class BindVisitor implements ExpressionVisitor
         DepotMarshaller marsh = _types.getMarshaller(insertClause.getPersistentClass());
 
         Object pojo = insertClause.getPojo();
-        String ixField = insertClause.getIndexField();
+        Set<String> generatedFields = insertClause.getIdentityFields();
         for (String field : marsh.getColumnFieldNames()) {
-            if (ixField == null || !ixField.equals(field)) {
+            if (!generatedFields.contains(field)) {
                 marsh.getFieldMarshaller(field).readFromObject(pojo, _stmt, _argIdx ++);
             }
         }

src/java/com/samskivert/jdbc/depot/BuildVisitor.java

@@ -24,6 +24,7 @@ import java.sql.SQLException;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 
 import com.samskivert.jdbc.depot.Key.WhereCondition;
 import com.samskivert.jdbc.depot.annotation.Computed;
@@ -450,12 +451,12 @@ public abstract class BuildVisitor implements ExpressionVisitor
         }
         _builder.append(") values(");
 
-        String ixField = insertClause.getIndexField();
+        Set<String> generatedFields = insertClause.getIdentityFields();
         for (int ii = 0; ii < fields.length; ii++) {
             if (ii > 0) {
                 _builder.append(", ");
             }
-            if (ixField != null && ixField.equals(fields[ii])) {
+            if (generatedFields.contains(fields[ii])) {
                 _builder.append("DEFAULT");
             } else {
                 _builder.append("?");

src/java/com/samskivert/jdbc/depot/DepotMarshaller.java

@@ -103,6 +103,8 @@ public class DepotMarshaller<T extends PersistentRecord>
             }
         }
 
+        boolean seenIdentityGenerator = false;
+
         // introspect on the class and create marshallers for persistent fields
         ArrayList<String> fields = new ArrayList<String>();
         for (Field field : _pclass.getFields()) {
@@ -136,38 +138,19 @@ public class DepotMarshaller<T extends PersistentRecord>
                     _pkColumns = new ArrayList<FieldMarshaller>();
                 }
                 _pkColumns.add(fm);
-
-                // check if this field defines a new TableGenerator
-                generator = field.getAnnotation(TableGenerator.class);
-                if (generator != null) {
-                    context.tableGenerators.put(generator.name(), generator);
-                }
-            }
-        }
-
-        // if the entity defines a single-columnar primary key, figure out if we will be generating
-        // values for it
-        if (_pkColumns != null) {
-            GeneratedValue gv = null;
-            FieldMarshaller keyField = null;
-            // loop over fields to see if there's a @GeneratedValue at all
-            for (FieldMarshaller field : _pkColumns) {
-                gv = field.getGeneratedValue();
-                if (gv != null) {
-                    keyField = field;
-                    break;
-                }
             }
 
-            if (keyField != null) {
+            // check if this field defines a new TableGenerator
-                // and if there is, make sure we've a single-column id
+            generator = field.getAnnotation(TableGenerator.class);
-                if (_pkColumns.size() > 1) {
+            if (generator != null) {
-                    throw new IllegalArgumentException(
+                context.tableGenerators.put(generator.name(), generator);
-                        "Cannot use @GeneratedValue on multiple-column @Id's");
+            }
-                }
 
-                // the primary key must be numeric if we are to auto-assign it
+            // check if this field is auto-generated
-                Class<?> ftype = keyField.getField().getType();
+            GeneratedValue gv = fm.getGeneratedValue();
+            if (gv != null) {
+                // we can only do this on numeric fields
+                Class<?> ftype = field.getType();
                 boolean isNumeric = (
                     ftype.equals(Byte.TYPE) || ftype.equals(Byte.class) ||
                     ftype.equals(Short.TYPE) || ftype.equals(Short.class) ||
@@ -175,14 +158,17 @@ public class DepotMarshaller<T extends PersistentRecord>
                     ftype.equals(Long.TYPE) || ftype.equals(Long.class));
                 if (!isNumeric) {
                     throw new IllegalArgumentException(
-                        "Cannot use @GeneratedValue on non-numeric column");
+                        "Cannot use @GeneratedValue on non-numeric column: " + field.getName());
                 }
-
                 switch(gv.strategy()) {
                 case AUTO:
                 case IDENTITY:
-                    _keyGenerator = new IdentityKeyGenerator(
+                    if (seenIdentityGenerator) {
-                        gv, getTableName(), keyField.getColumnName());
+                        throw new IllegalArgumentException(
+                            "Persistent records can have at most one AUTO/IDENTITY generator.");
+                    }
+                    _valueGenerators.put(field.getName(), new IdentityValueGenerator(gv, this, fm));
+                    seenIdentityGenerator = true;
                     break;
 
                 case TABLE:
@@ -192,11 +178,12 @@ public class DepotMarshaller<T extends PersistentRecord>
                         throw new IllegalArgumentException(
                             "Unknown generator [generator=" + name + "]");
                     }
-                    _keyGenerator = new TableKeyGenerator(
+                    _valueGenerators.put(
-                        generator, gv, getTableName(), keyField.getColumnName());
+                        field.getName(), new TableValueGenerator(generator, gv, this, fm));
                     break;
                 }
             }
+
         }
 
         // generate our full list of fields/columns for use in queries
@@ -270,12 +257,12 @@ public class DepotMarshaller<T extends PersistentRecord>
     }
 
     /**
-     * Returns the {@link KeyGenerator} used to generate primary keys for this persistent object,
+     * Returns the {@link ValueGenerator} used to generate primary keys for this persistent object,
      * or null if it does not use a key generator.
      */
-    public KeyGenerator getKeyGenerator ()
+    public Iterable<ValueGenerator> getValueGenerators ()
     {
-        return _keyGenerator;
+        return _valueGenerators.values();
     }
 
     /**
@@ -435,37 +422,40 @@ public class DepotMarshaller<T extends PersistentRecord>
     }
 
     /**
-     * Fills in the primary key just assigned to the supplied persistence object by the execution
+     * Go through the registered {@link ValueGenerator}s for our persistent object and run the
-     * of the results of {@link #createInsert}.
+     * ones that match the current postFactum phase, filling in the fields on the supplied object
+     * while we go. This method used to generate a key; that is now a separate step.
      *
-     * @return the newly assigned primary key or null if the object does not use primary keys or
+     * The return value is only non-empty for the !postFactum phase, in which case it is a set
-     * this is not the right time to assign the key.
+     * of field names that are associated with {@link IdentityValueGenerator}, because these need
+     * special handling in the INSERT (specifically, 'DEFAULT' must be supplied as a value in
+     * the eventual SQL).
      */
-    public Key assignPrimaryKey (
+    public Set<String> generateFieldValues (
         Connection conn, DatabaseLiaison liaison, Object po, boolean postFactum)
-        throws SQLException
     {
-        // if we have no primary key or no generator, then we're done
+        Set<String> idFields = new HashSet<String>();
-        if (!hasPrimaryKey() || _keyGenerator == null) {
-            return null;
-        }
 
-        // run this generator either before or after the actual insertion
+        for (ValueGenerator vg : _valueGenerators.values()) {
-        if (_keyGenerator.isPostFactum() != postFactum) {
+            if (!postFactum && vg instanceof IdentityValueGenerator) {
-            return null;
+                idFields.add(vg.getFieldMarshaller().getField().getName());
-        }
+            }
+            if (vg.isPostFactum() != postFactum) {
+                continue;
+            }
 
-        try {
+            try {
-            int nextValue = _keyGenerator.nextGeneratedValue(conn, liaison);
+                int nextValue = vg.nextGeneratedValue(conn, liaison);
-            _pkColumns.get(0).getField().set(po, nextValue);
+                vg.getFieldMarshaller().getField().set(po, nextValue);
-            return makePrimaryKey(nextValue);
+
-        } catch (Exception e) {
+            } catch (Exception e) {
-            String errmsg = "Failed to assign primary key [type=" + _pclass + "]";
+                throw new IllegalStateException(
-            throw (SQLException) new SQLException(errmsg).initCause(e);
+                    "Failed to assign primary key [type=" + _pclass + "]", e);
+            }
         }
+        return idFields;
     }
 
-
     /**
      * This is called by the persistence context to register a migration for the entity managed by
      * this marshaller.
@@ -575,9 +565,9 @@ public class DepotMarshaller<T extends PersistentRecord>
                             getTableName() + "_" + idx.name(), idx.unique());
                     }
 
-                    // its key generator
+                    // its value generators
-                    if (_keyGenerator != null) {
+                    for (ValueGenerator vg : _valueGenerators.values()) {
-                        _keyGenerator.init(conn, liaison);
+                        vg.init(conn, liaison);
                     }
 
                     // and its full text search indexes
@@ -969,6 +959,9 @@ public class DepotMarshaller<T extends PersistentRecord>
     /** The @Computed annotation of this entity, or null. */
     protected Computed _computed;
 
+    /** A mapping of field names to value generators for that field. */
+    protected Map<String, ValueGenerator> _valueGenerators = new HashMap<String, ValueGenerator>();
+
     /** A field marshaller for each persistent field in our object. */
     protected Map<String, FieldMarshaller> _fields = new HashMap<String, FieldMarshaller>();
 
@@ -976,9 +969,6 @@ public class DepotMarshaller<T extends PersistentRecord>
      * define a primary key. */
     protected ArrayList<FieldMarshaller> _pkColumns;
 
-    /** The generator to use for auto-generating primary key values, or null. */
-    protected KeyGenerator _keyGenerator;
-
     /** The persisent fields of our object, in definition order. */
     protected String[] _allFields;
 
@@ -999,4 +989,5 @@ public class DepotMarshaller<T extends PersistentRecord>
 
     /** The name of the table we use to track schema versions. */
     protected static final String SCHEMA_VERSION_TABLE = "DepotSchemaVersion";
+
 }

src/java/com/samskivert/jdbc/depot/DepotRepository.java

@@ -37,10 +37,7 @@ import com.samskivert.jdbc.JDBCUtil;
 
 import com.samskivert.jdbc.depot.Modifier.*;
 import com.samskivert.jdbc.depot.clause.DeleteClause;
-import com.samskivert.jdbc.depot.clause.FieldOverride;
-import com.samskivert.jdbc.depot.clause.FromOverride;
 import com.samskivert.jdbc.depot.clause.InsertClause;
-import com.samskivert.jdbc.depot.clause.Join;
 import com.samskivert.jdbc.depot.clause.QueryClause;
 import com.samskivert.jdbc.depot.clause.UpdateClause;
 import com.samskivert.jdbc.depot.expression.SQLExpression;
@@ -175,24 +172,26 @@ public abstract class DepotRepository
         // key will be null if record was supplied without a primary key
         return _ctx.invoke(new CachingModifier<T>(record, key, key) {
             public int invoke (Connection conn, DatabaseLiaison liaison) throws SQLException {
-                // update our modifier's key so that it can cache our results
+                // set any auto-generated column values
+                Set<String> identityFields = marsh.generateFieldValues(conn, liaison, _result, false);
+
+                // if needed, update our modifier's key so that it can cache our results
                 if (_key == null) {
-                    updateKey(marsh.assignPrimaryKey(conn, liaison, _result, false));
+                    updateKey(marsh.getPrimaryKey(_result, false));
                 }
 
-                String ixField = null;
+                builder.newQuery(new InsertClause<T>(pClass, _result, identityFields));
-                if (_key == null && marsh.hasPrimaryKey() && marsh.getKeyGenerator() != null &&
-                        marsh.getKeyGenerator() instanceof IdentityKeyGenerator) {
-                    ixField = ((IdentityKeyGenerator) marsh.getKeyGenerator()).getColumn();
-                }
-                builder.newQuery(new InsertClause<T>(pClass, _result, ixField));
 
                 PreparedStatement stmt = builder.prepare(conn);
                 try {
                     int mods = stmt.executeUpdate();
-                    // check again in case we have a post-factum key generator
+
+                    // run any post-factum value generators
+                    marsh.generateFieldValues(conn, liaison, _result, true);
+
+                    // and check once more if a key now exists
                     if (_key == null) {
-                        updateKey(marsh.assignPrimaryKey(conn, liaison, _result, true));
+                        updateKey(marsh.getPrimaryKey(_result, false));
                     }
                     return mods;
                 } finally {
@@ -575,22 +574,25 @@ public abstract class DepotRepository
                     }
 
                     // if the update modified zero rows or the primary key was obviously unset, do
-                    // an insertion
+                    // an insertion: first,  set any auto-generated column values
+                    Set<String> identityFields = marsh.generateFieldValues(conn, liaison, _result, false);
+
+                    // update our modifier's key so that it can cache our results
                     if (_key == null) {
-                        updateKey(marsh.assignPrimaryKey(conn, liaison, _result, false));
+                        updateKey(marsh.getPrimaryKey(_result, false));
                     }
 
-                    String ixField = null;
+                    builder.newQuery(new InsertClause<T>(pClass, _result, identityFields));
-                    if (_key == null && marsh.hasPrimaryKey() && marsh.getKeyGenerator() != null &&
-                            marsh.getKeyGenerator() instanceof IdentityKeyGenerator) {
-                        ixField = ((IdentityKeyGenerator) marsh.getKeyGenerator()).getColumn();
-                    }
-                    builder.newQuery(new InsertClause<T>(pClass, _result, ixField));
 
                     stmt = builder.prepare(conn);
                     int mods = stmt.executeUpdate();
+
+                    // run any post-factum value generators
+                    marsh.generateFieldValues(conn, liaison, _result, true);
+
+                    // and check once more if a key now exists
                     if (_key == null) {
-                        updateKey(marsh.assignPrimaryKey(conn, liaison, _result, true));
+                        updateKey(marsh.getPrimaryKey(_result, false));
                     }
                     created[0] = true;
                     return mods;

src/java/com/samskivert/jdbc/depot/FieldMarshaller.java

@@ -222,10 +222,8 @@ public abstract class FieldMarshaller<T>
             return;
         }
 
-        if (field.getAnnotation(Id.class) != null) {
+        // figure out how we're going to generate our primary key values
-            // figure out how we're going to generate our primary key values
+        _generatedValue = field.getAnnotation(GeneratedValue.class);
-            _generatedValue = field.getAnnotation(GeneratedValue.class);
-        }
     }
 
     protected static class BooleanMarshaller extends FieldMarshaller<Boolean> {

src/java/com/samskivert/jdbc/depot/IdentityValueGenerator.java

@@ -3,7 +3,7 @@
 //
 // samskivert library - useful routines for java programs
 // Copyright (C) 2006-2007 Michael Bayne, 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
@@ -24,17 +24,16 @@ import java.sql.Connection;
 import java.sql.SQLException;
 
 import com.samskivert.jdbc.DatabaseLiaison;
-import com.samskivert.jdbc.LiaisonRegistry;
 import com.samskivert.jdbc.depot.annotation.GeneratedValue;
 
 /**
  * Generates primary keys using an identity column.
  */
-public class IdentityKeyGenerator extends KeyGenerator
+public class IdentityValueGenerator extends ValueGenerator
 {
-    public IdentityKeyGenerator (GeneratedValue gv, String table, String column)
+    public IdentityValueGenerator (GeneratedValue gv, DepotMarshaller dm, FieldMarshaller fm)
     {
-        super(gv, table, column);
+        super(gv, dm, fm);
     }
 
     // from interface KeyGenerator
@@ -47,13 +46,14 @@ public class IdentityKeyGenerator extends KeyGenerator
     public void init (Connection conn, DatabaseLiaison liaison)
         throws SQLException
     {
-        liaison.initializeGenerator(conn, _table, _column, _initialValue, _allocationSize);
+        liaison.initializeGenerator(
+            conn, _dm.getTableName(), _fm.getColumnName(), _initialValue, _allocationSize);
     }
 
     // from interface KeyGenerator
     public int nextGeneratedValue (Connection conn, DatabaseLiaison liaison)
         throws SQLException
     {
-        return liaison.lastInsertedId(conn, _table, _column);
+        return liaison.lastInsertedId(conn, _dm.getTableName(), _fm.getColumnName());
     }
 }

src/java/com/samskivert/jdbc/depot/TableValueGenerator.java

@@ -30,16 +30,15 @@ import com.samskivert.jdbc.depot.annotation.TableGenerator;
 
 import com.samskivert.jdbc.DatabaseLiaison;
 import com.samskivert.jdbc.JDBCUtil;
-import com.samskivert.jdbc.LiaisonRegistry;
 
 /**
  * Generates primary keys using an external table .
  */
-public class TableKeyGenerator extends KeyGenerator
+public class TableValueGenerator extends ValueGenerator
 {
-    public TableKeyGenerator (TableGenerator tg, GeneratedValue gv, String table, String column)
+    public TableValueGenerator (TableGenerator tg, GeneratedValue gv, DepotMarshaller dm, FieldMarshaller fm)
     {
-        super(gv, table, column);
+        super(gv, dm, fm);
         _valueTable = defStr(tg.table(), "IdSequences");
         _pkColumnName = defStr(tg.pkColumnName(), "sequence");
         _pkColumnValue = defStr(tg.pkColumnValue(), "default");

src/java/com/samskivert/jdbc/depot/ValueGenerator.java

@@ -27,16 +27,16 @@ import com.samskivert.jdbc.DatabaseLiaison;
 import com.samskivert.jdbc.depot.annotation.GeneratedValue;
 
 /**
- * Defines the interface to our primary key generators.
+ * Defines the interface to our value generators.
  */
-public abstract class KeyGenerator
+public abstract class ValueGenerator
 {
-    public KeyGenerator (GeneratedValue gv, String table, String column)
+    public ValueGenerator (GeneratedValue gv, DepotMarshaller dm, FieldMarshaller fm)
     {
         _allocationSize = gv.allocationSize();
         _initialValue = gv.initialValue();
-        _table = table;
+        _dm = dm;
-        _column = column;
+        _fm = fm;
     }
 
     /**
@@ -57,24 +57,19 @@ public abstract class KeyGenerator
     public abstract int nextGeneratedValue (Connection conn, DatabaseLiaison liaison)
         throws SQLException;
 
-    /**
+
-     * Returns the name of the table for which we're generating a key value.
+    public DepotMarshaller getDepotMarshaller ()
-     */
-    public String getTable ()
     {
-        return _table;
+        return _dm;
     }
 
-    /**
+    public FieldMarshaller getFieldMarshaller ()
-     * Returns the name of the column for which we're generating a key value.
-     */
-    public String getColumn ()
     {
-        return _column;
+        return _fm;
     }
 
     protected int _initialValue;
     protected int _allocationSize;
-    protected String _table;
+    protected DepotMarshaller _dm;
-    protected String _column;
+    protected FieldMarshaller _fm;
 }

src/java/com/samskivert/jdbc/depot/clause/InsertClause.java

@@ -21,6 +21,7 @@
 package com.samskivert.jdbc.depot.clause;
 
 import java.util.Collection;
+import java.util.Set;
 
 import com.samskivert.jdbc.depot.PersistentRecord;
 import com.samskivert.jdbc.depot.expression.ExpressionVisitor;
@@ -30,11 +31,12 @@ import com.samskivert.jdbc.depot.expression.ExpressionVisitor;
  */
 public class InsertClause<T extends PersistentRecord> extends QueryClause
 {
-    public InsertClause (Class<? extends PersistentRecord> pClass, Object pojo, String ixField)
+    public InsertClause (
+        Class<? extends PersistentRecord> pClass, Object pojo, Set<String> identityFields)
     {
         _pClass = pClass;
         _pojo = pojo;
-        _ixField = ixField;
+        _idFields = identityFields;
     }
 
     public Class<? extends PersistentRecord> getPersistentClass ()
@@ -47,9 +49,9 @@ public class InsertClause<T extends PersistentRecord> extends QueryClause
         return _pojo;
     }
 
-    public String getIndexField ()
+    public Set<String> getIdentityFields ()
     {
-        return _ixField;
+        return _idFields;
     }
 
     // from SQLExpression
@@ -70,5 +72,5 @@ public class InsertClause<T extends PersistentRecord> extends QueryClause
     /** The object from which to fetch values, or null. */
     protected Object _pojo;
 
-    protected String _ixField;
+    protected Set<String> _idFields;
 }