Fix findColumn and get*(String label) methods.

The ResultSet `findColumn` methods (`BQForwardOnlyResultSet.findColumn`,
`BQScrollableResultSet.findColumn`, and `BQResultSet.findColumn`) called
`BQResultSetMetadata.getCatalogName` to determine the name of each column
instead of `BQResultSetMetadata.getColumnLabel`.

This was wrong because `getCatalogName` always returns the BigQuery project ID,
not the column name.

This bug in turn broke the get methods that are implemented in terms of
`findColumn`, e.g. `getString(String)`.

This change fixes `findColumn` and adds tests for methods that use it with some
caveats:

- `BQResultSet` has its findColumn fixed but it's not tested. That's because
its unused, even by its tests, which request a `TYPE_SCROLL_INSENSITIVE`
result set and thus get a `BQScrollableResultSet`.

- `BQScrollableResultSet` only accepts dates and times that can be parsed as
longs, which disagrees with the more widely used `BQForwardOnlyResultSet`.
Its date and time accessors are uncovered.

- `getBigDecimal` is excluded because it calls `BigDecimal.setScale`
without a rounding mode, which no longer works in modern Java. A
separate change can fix this.

src/main/java/net/starschema/clouddb/jdbc/BQForwardOnlyResultSet.java

@@ -61,7 +61,12 @@
 import java.sql.Statement;
 import java.sql.Time;
 import java.sql.Timestamp;
-import java.util.*;
+import java.util.ArrayList;
+import java.util.Calendar;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Optional;
 import javax.annotation.Nullable;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -593,12 +598,13 @@ public void deleteRow() throws SQLException {
    */
   @Override
   public int findColumn(String columnLabel) throws SQLException {
-    if (this.isClosed()) {
+    if (isClosed()) {
       throw new BQSQLException("This Resultset is Closed");
     }
-    int columncount = this.getMetaData().getColumnCount();
-    for (int i = 1; i <= columncount; i++) {
-      if (this.getMetaData().getCatalogName(i).equals(columnLabel)) {
+    final ResultSetMetaData metadata = this.getMetaData();
+    int columns = metadata.getColumnCount();
+    for (int i = 1; i <= columns; i++) {
+      if (metadata.getColumnLabel(i).equals(columnLabel)) {
         return i;
       }
     }

src/main/java/net/starschema/clouddb/jdbc/BQResultSet.java

@@ -112,9 +112,10 @@ public int findColumn(String columnLabel) throws SQLException {
     if (this.isClosed()) {
       throw new BQSQLException("This Resultset is Closed");
     }
-    int columncount = this.getMetaData().getColumnCount();
-    for (int i = 1; i <= columncount; i++) {
-      if (this.getMetaData().getCatalogName(i).equals(columnLabel)) {
+    final ResultSetMetaData metadata = this.getMetaData();
+    int columns = metadata.getColumnCount();
+    for (int i = 1; i <= columns; i++) {
+      if (metadata.getColumnLabel(i).equals(columnLabel)) {
         return i;
       }
     }

src/main/java/net/starschema/clouddb/jdbc/BQScrollableResultSet.java

@@ -140,9 +140,10 @@ public int findColumn(String columnLabel) throws SQLException {
     if (this.isClosed()) {
       throw new BQSQLException("This Resultset is Closed");
     }
-    int columncount = this.getMetaData().getColumnCount();
-    for (int i = 1; i <= columncount; i++) {
-      if (this.getMetaData().getCatalogName(i).equals(columnLabel)) {
+    final ResultSetMetaData metadata = this.getMetaData();
+    int columns = metadata.getColumnCount();
+    for (int i = 1; i <= columns; i++) {
+      if (metadata.getColumnLabel(i).equals(columnLabel)) {
         return i;
       }
     }

src/test/java/net/starschema/clouddb/jdbc/BQForwardOnlyResultSetFunctionTest.java

@@ -28,6 +28,7 @@
 import com.google.gson.Gson;
 import java.io.IOException;
 import java.math.BigDecimal;
+import java.sql.Connection;
 import java.sql.DriverManager;
 import java.sql.ResultSet;
 import java.sql.SQLException;
@@ -58,7 +59,7 @@
  * @author Horváth Attila
  * @author Gunics Balazs
  */
-public class BQForwardOnlyResultSetFunctionTest {
+public class BQForwardOnlyResultSetFunctionTest extends CommonTestsForResultSets {
 
   private static java.sql.Connection con = null;
   private java.sql.ResultSet resultForTest = null;
@@ -845,4 +846,10 @@ public void testStatelessQuery() throws SQLException {
     Assertions.assertThat(bqResultSet.getJobId()).isNull();
     Assertions.assertThat(bqResultSet.getQueryId()).contains("!");
   }
+
+  @Override
+  protected Statement createStatementForCommonTests(final Connection connection)
+      throws SQLException {
+    return connection.createStatement(ResultSet.TYPE_FORWARD_ONLY, ResultSet.CONCUR_READ_ONLY);
+  }
 }

src/test/java/net/starschema/clouddb/jdbc/BQScrollableResultSetFunctionTest.java

@@ -22,6 +22,7 @@
 
 import com.google.api.client.testing.http.MockHttpTransport;
 import com.google.api.client.testing.http.MockLowLevelHttpResponse;
+import java.sql.Connection;
 import java.sql.DriverManager;
 import java.sql.ResultSet;
 import java.sql.SQLException;
@@ -31,6 +32,7 @@
 import org.assertj.core.api.Assertions;
 import org.junit.After;
 import org.junit.Before;
+import org.junit.Ignore;
 import org.junit.Test;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -41,7 +43,7 @@
  * @author Horváth Attila
  * @author Gunics Balazs
  */
-public class BQScrollableResultSetFunctionTest {
+public class BQScrollableResultSetFunctionTest extends CommonTestsForResultSets {
 
   private static java.sql.Connection con = null;
   private static java.sql.ResultSet Result = null;
@@ -745,4 +747,31 @@ public void testStatelessQuery() throws SQLException {
     Assertions.assertThat(bqResultSet.getJobId()).isNull();
     Assertions.assertThat(bqResultSet.getQueryId()).contains("!");
   }
+
+  @Override
+  protected Statement createStatementForCommonTests(Connection connection) throws SQLException {
+    return connection.createStatement(
+        ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_READ_ONLY);
+  }
+
+  @Override
+  @Test
+  @Ignore(
+      "Contradiction between BQSCrollableResultSet and BQForwardOnlyResultSet "
+          + "dates and times: b/317107706")
+  public void testGetTimeByLabel() throws SQLException {}
+
+  @Override
+  @Test
+  @Ignore(
+      "Contradiction between BQSCrollableResultSet and BQForwardOnlyResultSet "
+          + "dates and times: b/317107706")
+  public void testGetDateByLabel() throws SQLException {}
+
+  @Override
+  @Test
+  @Ignore(
+      "Contradiction between BQSCrollableResultSet and BQForwardOnlyResultSet "
+          + "dates and times: b/317107706")
+  public void testGetTimestampByLabel() throws SQLException {}
 }