Java functions: array component types are now preserved, so that a…

Java functions: array component types are now preserved, so that a ResultSet.getObject() will return Integer[] if the Java functions returns Integer[]. Thanks to Noel Grandin for the patch.

h2/src/docsrc/html/changelog.html

@@ -18,7 +18,9 @@ Change Log
 <h1>Change Log</h1>
 
 <h2>Next Version (unreleased)</h2>
-<ul><li>Recover tool: the script generated by the recover tool didn't work 
+<ul><li>Java functions: array component types are now preserved, so that a ResultSet.getObject()
+    will return Integer[] if the Java functions returns Integer[]. Thanks to Noel Grandin for the patch.
+</li><li>Recover tool: the script generated by the recover tool didn't work 
     if fulltext search was used, because the triggers were created before the primary keys.
 </li><li>Issue 321: the database does not expect XA rollback without XA prepare
     (an exception was unnecessarily written into the .trace.db file).

h2/src/main/org/h2/engine/FunctionAlias.java

@@ -30,6 +30,7 @@ import org.h2.util.StringUtils;
 import org.h2.util.Utils;
 import org.h2.value.DataType;
 import org.h2.value.Value;
+import org.h2.value.ValueArray;
 import org.h2.value.ValueNull;
 
 /**
@@ -352,6 +353,14 @@ public class FunctionAlias extends SchemaObjectBase {
                 Object o;
                 if (Value.class.isAssignableFrom(paramClass)) {
                     o = v;
+                } else if (v.getType() == Value.ARRAY && paramClass.isArray() && paramClass.getComponentType() != Object.class) {
+                    Value[] array = ((ValueArray) v).getList();
+                    Object[] objArray = (Object[]) Array.newInstance(paramClass.getComponentType(), array.length);
+                    int componentType = DataType.getTypeFromClass(paramClass.getComponentType());
+                    for (int i = 0; i < objArray.length; i++) {
+                        objArray[i] = array[i].convertTo(componentType).getObject();
+                    }
+                    o = objArray;
                 } else {
                     v = v.convertTo(type);
                     o = v.getObject();

h2/src/main/org/h2/value/DataType.java

@@ -917,7 +917,7 @@ public class DataType {
             for (int i = 0; i < len; i++) {
                 v[i] = convertToValue(session, o[i], type);
             }
-            return ValueArray.get(v);
+            return ValueArray.get(x.getClass().getComponentType(), v);
         } else if (x instanceof Character) {
             return ValueStringFixed.get(((Character) x).toString());
         } else {

h2/src/main/org/h2/value/ValueArray.java

@@ -6,6 +6,7 @@
  */
 package org.h2.value;
 
+import java.lang.reflect.Array;
 import java.sql.PreparedStatement;
 import java.util.ArrayList;
 import org.h2.engine.Constants;
@@ -18,13 +19,19 @@ import org.h2.util.StatementBuilder;
  */
 public class ValueArray extends Value {
 
+    private final Class<?> componentType;
     private final Value[] values;
     private int hash;
 
-    private ValueArray(Value[] list) {
+    private ValueArray(Class<?> componentType, Value[] list) {
+        this.componentType = componentType;
         this.values = list;
     }
     
+    private ValueArray(Value[] list) {
+        this(Object.class, list);
+    }
+
     /**
      * Get or create a array value for the given value array.
      * Do not clone the data.
@@ -36,6 +43,17 @@ public class ValueArray extends Value {
         return new ValueArray(list);
     }
 
+    /**
+     * Get or create a array value for the given value array.
+     * Do not clone the data.
+     *
+     * @param list the value array
+     * @return the value
+     */
+    public static ValueArray get(Class<?> componentType, Value[] list) {
+        return new ValueArray(componentType, list);
+    }
+    
     public int hashCode() {
         if (hash != 0) {
             return hash;
@@ -56,6 +74,10 @@ public class ValueArray extends Value {
         return Value.ARRAY;
     }
     
+    public Class<?> getComponentType() {
+        return componentType;
+    }
+
     public long getPrecision() {
         long p = 0;
         for (Value v : values) {
@@ -94,7 +116,7 @@ public class ValueArray extends Value {
 
     public Object getObject() {
         int len = values.length;
-        Object[] list = new Object[len];
+        Object[] list = (Object[]) Array.newInstance(componentType, len);
         for (int i = 0; i < len; i++) {
             list[i] = values[i].getObject();
         }

h2/src/test/org/h2/test/TestBase.java

@@ -578,6 +578,30 @@ public abstract class TestBase {
         }
     }
 
+    /**
+     * Check if two values are equal, and if not throw an exception.
+     *
+     * @param expected the expected value
+     * @param actual the actual value
+     * @throws AssertionError if the values are not equal
+     */
+    public void assertEquals(Object[] expected, Object[] actual) {
+        if (expected == null || actual == null) {
+            assertTrue(expected == actual);
+            return;
+        }
+        assertEquals(expected.length, actual.length);
+        for (int i = 0; i < expected.length; i++) {
+            if (expected[i] == null || actual[i] == null) {
+                if (expected[i] != actual[i]) {
+                    fail("[" + i + "]: expected: " + expected[i] + " actual: " + actual[i]);
+                }
+            } else if (!expected[i].equals(actual[i])) {
+                fail("[" + i + "]: expected: " + expected[i] + " actual: " + actual[i]);
+            }
+        }
+    }
+    
     /**
      * Check if two readers are equal, and if not throw an exception.
      *

h2/src/test/org/h2/test/db/TestFunctions.java

@@ -13,6 +13,7 @@ import java.io.OutputStream;
 import java.math.BigDecimal;
 import java.sql.Array;
 import java.sql.Blob;
+import java.sql.CallableStatement;
 import java.sql.Connection;
 import java.sql.DatabaseMetaData;
 import java.sql.DriverManager;
@@ -50,6 +51,7 @@ public class TestFunctions extends TestBase implements AggregateFunction {
 
     public void test() throws Exception {
         deleteDb("functions");
+        testArrayParameters();
         testDefaultConnection();
         testFunctionInSchema();
         testGreatest();
@@ -731,6 +733,33 @@ public class TestFunctions extends TestBase implements AggregateFunction {
         conn.close();
     }
 
+    private void testArrayParameters() throws SQLException {
+        deleteDb("functions");
+        Connection conn = getConnection("functions");
+        Statement stat = conn.createStatement();
+        ResultSet rs;
+        stat.execute("create alias array_test AS "
+                + "$$ Integer[] array_test(Integer[] in_array) "
+                + "{ return in_array; } $$;");
+
+        PreparedStatement stmt = conn.prepareStatement("select array_test(?) from dual");
+        stmt.setObject(1, new Integer[] { 1, 2 });
+        rs = stmt.executeQuery();
+        rs.next();
+        assertEquals(Integer[].class.getName(), rs.getObject(1).getClass().getName());
+
+        CallableStatement call = conn.prepareCall("{ ? = call array_test(?) }");
+        call.setObject(2, new Integer[] { 2, 1 });
+        call.registerOutParameter(1, Types.ARRAY);
+        call.execute();
+        assertEquals(Integer[].class.getName(), call.getArray(1).getArray().getClass().getName());
+        assertEquals(new Integer[] { 2, 1 }, (Integer[]) call.getObject(1));
+
+        stat.execute("drop alias array_test");
+
+        conn.close();
+    }
+
     private void assertCallResult(String expected, Statement stat, String sql) throws SQLException {
         ResultSet rs = stat.executeQuery("CALL " + sql);
         rs.next();