A prepared statement if type CALL that returned a result set could throw a…

A prepared statement if type CALL that returned a result set could throw a NullPointerExecption if executed multiple times.

h2/src/main/org/h2/command/dml/Call.java

@@ -15,7 +15,6 @@ import org.h2.expression.ExpressionVisitor;
 import org.h2.result.LocalResult;
 import org.h2.result.ResultInterface;
 import org.h2.value.Value;
-import org.h2.value.ValueResultSet;
 
 /**
  * This class represents the statement
@@ -23,6 +22,7 @@ import org.h2.value.ValueResultSet;
  */
 public class Call extends Prepared {
 
+    private boolean isResultSet;
     private Expression expression;
     private Expression[] expressions;
 
@@ -31,9 +31,8 @@ public class Call extends Prepared {
     }
 
     public ResultInterface queryMeta() {
-        int expressionType = expression.getType();
         LocalResult result;
-        if (expressionType == Value.RESULT_SET) {
+        if (isResultSet) {
             Expression[] expr = expression.getExpressionColumns(session);
             result = new LocalResult(session, expr, expr.length);
         } else {
@@ -62,8 +61,9 @@ public class Call extends Prepared {
     public ResultInterface query(int maxrows) {
         setCurrentRowNumber(1);
         Value v = expression.getValue(session);
-        if (v.getType() == Value.RESULT_SET) {
-            ResultSet rs = ((ValueResultSet) v).getResultSet();
+        if (isResultSet) {
+            v = v.convertTo(Value.RESULT_SET);
+            ResultSet rs = v.getResultSet();
             return LocalResult.read(session, rs, maxrows);
         }
         LocalResult result = new LocalResult(session, expressions, 1);
@@ -76,6 +76,10 @@ public class Call extends Prepared {
     public void prepare() {
         expression = expression.optimize(session);
         expressions = new Expression[] { expression };
+        isResultSet = expression.getType() == Value.RESULT_SET;
+        if (isResultSet) {
+            prepareAlways = true;
+        }
     }
 
     public void setExpression(Expression expression) {
@@ -99,4 +103,8 @@ public class Call extends Prepared {
         return CommandInterface.CALL;
     }
 
+    public boolean isCacheable() {
+        return !isResultSet;
+    }
+
 }

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

@@ -13,6 +13,7 @@ import java.lang.ref.SoftReference;
 import java.math.BigDecimal;
 import java.sql.Date;
 import java.sql.PreparedStatement;
+import java.sql.ResultSet;
 import java.sql.SQLException;
 import java.sql.Time;
 import java.sql.Timestamp;
@@ -24,6 +25,7 @@ import org.h2.store.DataHandler;
 import org.h2.store.LobStorage;
 import org.h2.tools.SimpleResultSet;
 import org.h2.util.IOUtils;
+import org.h2.util.MathUtils;
 import org.h2.util.StringUtils;
 import org.h2.util.Utils;
 
@@ -1068,6 +1070,13 @@ public abstract class Value {
         return this;
     }
 
+    public ResultSet getResultSet() {
+        SimpleResultSet rs = new SimpleResultSet();
+        rs.addColumn("X", DataType.convertTypeToSQLType(getType()), MathUtils.convertLongToInt(getPrecision()), getScale());
+        rs.addRow(getObject());
+        return rs;
+    }
+
     /**
      * A "binary large object".
      */

h2/src/test/org/h2/test/jdbc/TestPreparedStatement.java

@@ -44,6 +44,7 @@ public class TestPreparedStatement extends TestBase {
     public void test() throws Exception {
         deleteDb("preparedStatement");
         Connection conn = getConnection("preparedStatement");
+        testCallTablePrepared(conn);
         testValues(conn);
         testToString(conn);
         testExecuteUpdateCall(conn);
@@ -80,6 +81,12 @@ public class TestPreparedStatement extends TestBase {
         deleteDb("preparedStatement");
     }
 
+    private void testCallTablePrepared(Connection conn) throws SQLException {
+        PreparedStatement prep = conn.prepareStatement("call table(x int = (1))");
+        prep.executeQuery();
+        prep.executeQuery();
+    }
+
     private void testValues(Connection conn) throws SQLException {
         PreparedStatement prep = conn.prepareStatement("values(?, ?)");
         prep.setInt(1, 1);