ADD: Test and possible fix for (C)LOBs being handed out of connnection-context

Signed-off-by: Jonas Pöhler (JPo) <jonas.poehler@foconis.de>

ebean-core/src/main/java/io/ebeaninternal/server/rawsql/DRawSqlService.java

@@ -9,6 +9,7 @@ import io.ebeaninternal.server.query.DefaultSqlRow;
 import java.sql.ResultSet;
 import java.sql.ResultSetMetaData;
 import java.sql.SQLException;
+import java.sql.Types;
 
 public class DRawSqlService implements SpiRawSqlService {
 
@@ -49,6 +50,26 @@ public class DRawSqlService implements SpiRawSqlService {
         name = combine(meta.getSchemaName(i), meta.getTableName(i), name);
       }
       ret.put(name, resultSet.getObject(i));
+
+      // convert (C/B)LOBs to java objects.
+      // A java.sql.Clob depends on an open connection, so storing this object in a map
+      // that is accessed later, when the connection is closed, will result in a "connection is closed" exception.
+      // From the java.sql.Clob documentation: "... which means that a Clob object contains a logical pointer to the SQL CLOB
+      // data rather than the data itself."
+      switch (meta.getColumnType(i)) {
+        case Types.CLOB:
+        case Types.NCLOB:
+          ret.put(name, resultSet.getString(i));
+          break;
+
+        case Types.BLOB:
+          ret.put(name, resultSet.getBytes(i));
+          break;
+
+        default:
+          ret.put(name, resultSet.getObject(i));
+          break;
+      }
     }
     return ret;
   }

ebean-core/src/test/java/io/ebeaninternal/server/rawsql/TestRawSqlBuilder.java

@@ -9,17 +9,26 @@ import io.ebean.RawSqlBuilder;
 import io.ebean.SqlRow;
 import io.ebean.annotation.ForPlatform;
 import io.ebean.annotation.Platform;
+import io.ebean.datasource.DataSourceConfig;
+import io.ebeaninternal.server.core.DefaultServer;
 import io.ebeaninternal.server.rawsql.SpiRawSql.Sql;
 import org.junit.Test;
 import org.tests.model.basic.Customer;
+import org.tests.model.basic.EBasicClob;
+import org.tests.model.basic.PersistentFileContent;
 import org.tests.model.basic.ResetBasicData;
 import org.tests.model.rawsql.ERawSqlAggBean;
 
 import javax.sql.DataSource;
+import java.nio.charset.StandardCharsets;
+import java.sql.Blob;
 import java.sql.Connection;
+import java.sql.DriverManager;
 import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.SQLException;
+import java.util.ArrayList;
+import java.util.List;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.junit.Assert.assertEquals;
@@ -283,4 +292,59 @@ public class TestRawSqlBuilder extends BaseTestCase {
     }
   }
 
+  @Test
+  public void testCLobClosedConnection() throws Exception {
+    final EBasicClob eBasicClob = new EBasicClob();
+    eBasicClob.setName("eBasicClob");
+    final String description = "This is the CLob description";
+    eBasicClob.setDescription(description);
+    DB.save(eBasicClob);
+
+    final String sql = "select description from ebasic_clob where id = ?";
+
+    List<SqlRow> rows = new ArrayList<>();
+    final DataSourceConfig config = ((DefaultServer) DB.getDefault()).getServerConfig().getDataSourceConfig();
+
+    try (Connection connection = DriverManager.getConnection(config.getUrl(), config.getUsername(), config.getPassword());
+         PreparedStatement stmt = connection.prepareStatement(sql)) {
+      stmt.setLong(1, eBasicClob.getId());
+
+      try (ResultSet resultSet = stmt.executeQuery()) {
+        while (resultSet.next()) {
+          rows.add(RawSqlBuilder.sqlRow(resultSet, "true", false));
+        }
+      }
+    }
+
+    assertThat(rows).hasSize(1);
+    assertThat(rows.get(0).getString("description")).isEqualTo(description);
+  }
+
+  @Test
+  public void testBLobClosedConnection() throws Exception {
+    final PersistentFileContent pfc = new PersistentFileContent();
+    final byte[] bytes = "This is the blob as String".getBytes(StandardCharsets.UTF_8);
+    pfc.setContent(bytes);
+    DB.save(pfc);
+
+    final String sql = "select content from persistent_file_content where id = ?";
+
+    List<SqlRow> rows = new ArrayList<>();
+    final DataSourceConfig config = ((DefaultServer) DB.getDefault()).getServerConfig().getDataSourceConfig();
+
+    try (Connection connection = DriverManager.getConnection(config.getUrl(), config.getUsername(), config.getPassword());
+         PreparedStatement stmt = connection.prepareStatement(sql)) {
+      stmt.setLong(1, pfc.getId());
+
+      try (ResultSet resultSet = stmt.executeQuery()) {
+        while (resultSet.next()) {
+          rows.add(RawSqlBuilder.sqlRow(resultSet, "true", false));
+        }
+      }
+    }
+
+    assertThat(rows).hasSize(1);
+    assertThat(((Blob) rows.get(0).get("content")).getBytes(0, bytes.length)).isEqualTo(bytes);
+  }
+
 }