fix: NPE was thrown when getting an array of structs from a ResultSet

src/main/java/com/google/cloud/spanner/jdbc/JdbcDataType.java

@@ -17,6 +17,7 @@
 package com.google.cloud.spanner.jdbc;
 
 import com.google.cloud.spanner.ResultSet;
+import com.google.cloud.spanner.Struct;
 import com.google.cloud.spanner.Type;
 import com.google.cloud.spanner.Type.Code;
 import java.math.BigDecimal;
@@ -253,6 +254,32 @@ public List<Timestamp> getArrayElements(ResultSet rs, int columnIndex) {
  public Type getSpannerType() {
  return Type.timestamp();
  }
+ },
+ STRUCT {
+ @Override
+ public int getSqlType() {
+ return Types.STRUCT;
+ }
+
+ @Override
+ public Class<Struct> getJavaClass() {
+ return Struct.class;
+ }
+
+ @Override
+ public Code getCode() {
+ return Code.STRUCT;
+ }
+
+ @Override
+ public List<Struct> getArrayElements(ResultSet rs, int columnIndex) {
+ return rs.getStructList(columnIndex);
+ }
+
+ @Override
+ public Type getSpannerType() {
+ return Type.struct();
+ }
  };
 
  public abstract int getSqlType();

src/test/java/com/google/cloud/spanner/jdbc/JdbcArrayTest.java

@@ -18,15 +18,19 @@
 
 import static com.google.cloud.spanner.jdbc.JdbcTypeConverter.toSqlDate;
 import static com.google.common.truth.Truth.assertThat;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertThrows;
 import static org.junit.Assert.fail;
 
 import com.google.cloud.spanner.ErrorCode;
+import com.google.cloud.spanner.Struct;
 import com.google.cloud.spanner.jdbc.JdbcSqlExceptionFactory.JdbcSqlExceptionImpl;
 import java.math.BigDecimal;
 import java.sql.Date;
 import java.sql.ResultSet;
 import java.sql.ResultSetMetaData;
 import java.sql.SQLException;
+import java.sql.SQLFeatureNotSupportedException;
 import java.sql.Timestamp;
 import java.sql.Types;
 import org.junit.Test;
@@ -174,16 +178,17 @@ public void testCreateArrayOfArray() {
  }
 
  @Test
- public void testCreateArrayOfStruct() {
- try {
- JdbcArray.createArray("STRUCT", new Object[] {});
- fail("missing expected exception");
- } catch (SQLException e) {
- assertThat((Exception) e).isInstanceOf(JdbcSqlException.class);
- JdbcSqlException jse = (JdbcSqlException) e;
- assertThat(jse.getErrorCode())
- .isEqualTo(ErrorCode.INVALID_ARGUMENT.getGrpcStatusCode().value());
- }
+ public void testCreateArrayOfStruct() throws SQLException {
+ JdbcArray array =
+ JdbcArray.createArray(
+ "STRUCT",
+ new Struct[] {Struct.newBuilder().set("f1").to("v1").set("f2").to(1L).build(), null});
+ assertEquals(Types.STRUCT, array.getBaseType());
+ assertThat((Struct[]) array.getArray())
+ .asList()
+ .containsExactly(Struct.newBuilder().set("f1").to("v1").set("f2").to(1L).build(), null)
+ .inOrder();
+ assertThrows(SQLFeatureNotSupportedException.class, () -> array.getResultSet());
  }
 
  @Test

src/test/java/com/google/cloud/spanner/jdbc/it/ITJdbcSimpleStatementsTest.java

@@ -17,14 +17,22 @@
 package com.google.cloud.spanner.jdbc.it;
 
 import static com.google.common.truth.Truth.assertThat;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertThrows;
+import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
 
 import com.google.cloud.spanner.IntegrationTest;
+import com.google.cloud.spanner.Struct;
+import com.google.cloud.spanner.Value;
 import com.google.cloud.spanner.jdbc.ITAbstractJdbcTest;
+import java.sql.Array;
 import java.sql.Connection;
 import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.SQLException;
+import java.sql.SQLFeatureNotSupportedException;
 import java.sql.Statement;
 import org.junit.Test;
 import org.junit.experimental.categories.Category;
@@ -149,4 +157,38 @@ public void testAddBatchWhenAlreadyInBatch() {
  "Calling addBatch() is not allowed when a DML or DDL batch has been started on the connection.");
  }
  }
+
+ @Test
+ public void testSelectArrayOfStructs() throws SQLException {
+ String sql =
+ "WITH points AS\n"
+ + " (SELECT [1, 5] as point\n"
+ + " UNION ALL SELECT [2, 8] as point\n"
+ + " UNION ALL SELECT [3, 7] as point\n"
+ + " UNION ALL SELECT [4, 1] as point\n"
+ + " UNION ALL SELECT [5, 7] as point)\n"
+ + "SELECT ARRAY(\n"
+ + " SELECT STRUCT(point)\n"
+ + " FROM points)\n"
+ + " AS coordinates";
+ try (Connection connection = createConnection()) {
+ try (ResultSet resultSet = connection.createStatement().executeQuery(sql)) {
+ assertTrue(resultSet.next());
+ assertEquals(resultSet.getMetaData().getColumnCount(), 1);
+ Array array = resultSet.getArray(1);
+ assertThat((Struct[]) array.getArray())
+ .asList()
+ .containsExactly(
+ Struct.newBuilder().set("point").to(Value.int64Array(new long[] {1L, 5L})).build(),
+ Struct.newBuilder().set("point").to(Value.int64Array(new long[] {2L, 8L})).build(),
+ Struct.newBuilder().set("point").to(Value.int64Array(new long[] {3L, 7L})).build(),
+ Struct.newBuilder().set("point").to(Value.int64Array(new long[] {4L, 1L})).build(),
+ Struct.newBuilder().set("point").to(Value.int64Array(new long[] {5L, 7L})).build());
+ // Getting a result set from an array of structs is not supported, as structs are not
+ // supported as a valid column type in a result set.
+ assertThrows(SQLFeatureNotSupportedException.class, () -> array.getResultSet());
+ assertFalse(resultSet.next());
+ }
+ }
+ }
 }