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/*
 * Firebird Open Source JDBC Driver
 *
 * Distributable under LGPL license.
 * You may obtain a copy of the License at http://www.gnu.org/copyleft/lgpl.html
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * LGPL License for more details.
 *
 * This file was created by members of the firebird development team.
 * All individual contributions remain the Copyright (C) of those
 * individuals.  Contributors to this file are either listed here or
 * can be obtained from a source control history command.
 *
 * All rights reserved.
 */
package org.firebirdsql.jdbc;

import org.firebirdsql.gds.ISCConstants;
import org.firebirdsql.gds.impl.GDSHelper;
import org.firebirdsql.gds.ng.fields.FieldDescriptor;
import org.firebirdsql.gds.ng.fields.RowDescriptor;
import org.firebirdsql.jdbc.field.JdbcTypeConverter;
import org.firebirdsql.util.InternalApi;

import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.sql.Types;
import java.util.*;

import static org.firebirdsql.jaybird.util.StringUtils.isNullOrEmpty;

/**
 * Information about the types and properties of the columns in a {@link ResultSet} object.
 * 

* This class is internal API of Jaybird. Future versions may radically change, move, or make inaccessible this type. * For the public API, refer to the {@link ResultSetMetaData} and {@link FirebirdResultSetMetaData} interfaces. *

* * @author David Jencks * @author Mark Rotteveel */ @SuppressWarnings("RedundantThrows") @InternalApi public class FBResultSetMetaData extends AbstractFieldMetaData implements FirebirdResultSetMetaData { private final ColumnStrategy columnStrategy; /** * Creates a new {@code FBResultSetMetaData} instance. * * @param rowDescriptor * a row descriptor * @param connection * a {@code FBConnection} value * @throws SQLException * if an error occurs */ //TODO Need another constructor for metadata from constructed result set, where we supply the ext field info. protected FBResultSetMetaData(RowDescriptor rowDescriptor, FBConnection connection) throws SQLException { super(rowDescriptor, connection); // Decide how to handle column names and column labels if (isColumnLabelForName(connection)) { columnStrategy = ColumnStrategy.COLUMN_LABEL_FOR_NAME; } else { columnStrategy = ColumnStrategy.DEFAULT; } } private static boolean isColumnLabelForName(FBConnection connection) throws SQLException { if (connection == null) { return false; } GDSHelper gdsHelper = connection.getGDSHelper(); return gdsHelper != null && gdsHelper.getConnectionProperties().isColumnLabelForName(); } @Override public int getColumnCount() throws SQLException { return getFieldCount(); } /** * {@inheritDoc} */ @Override public boolean isAutoIncrement(int column) throws SQLException { return switch (getColumnType(column)) { case Types.SMALLINT, Types.INTEGER, Types.BIGINT -> { ExtendedFieldInfo extFieldInfo = getExtFieldInfo(column); yield extFieldInfo != null && extFieldInfo.autoIncrement(); } default -> false; }; } /** * {@inheritDoc} *

* The current implementation always returns {@code true}. *

*/ @Override public boolean isCaseSensitive(int column) throws SQLException { return true; } @Override public boolean isSearchable(int column) throws SQLException { final int sqlType = getFieldDescriptor(column).getType() & ~1; return !((sqlType == ISCConstants.SQL_ARRAY) || (sqlType == ISCConstants.SQL_BLOB)); } @Override public boolean isCurrency(int column) throws SQLException { return false; } @Override public int isNullable(int column) throws SQLException { return (getFieldDescriptor(column).getType() & 1) == 1 ? ResultSetMetaData.columnNullable : ResultSetMetaData.columnNoNulls; } @Override public boolean isSigned(int column) throws SQLException { return isSignedInternal(column); } @Override public int getColumnDisplaySize(int column) throws SQLException { final int precision = getPrecision(column); return switch (getColumnType(column)) { case Types.DECIMAL, Types.NUMERIC -> precision + 2; // sign + decimal separator case Types.FLOAT -> 7 + 6; // 7: number of decimal digits, 6: sign + decimal separator + E + sign exp + exp (2 pos) case Types.DOUBLE -> 15 + 7; // 15: number of decimal digits, 7: sign + decimal separator + E + sign exp + exp (3 pos) case Types.INTEGER, Types.BIGINT, Types.SMALLINT -> precision + 1; // sign case JaybirdTypeCodes.DECFLOAT -> { if (precision == 16) { yield 16 + 7; // 7: sign + decimal separator + E + sign exp + exp (3 pos) } yield 34 + 8; // 8: sign + decimal separator + E + sign exp + exp (4 pos) } case Types.BOOLEAN -> 5; // assuming displaying true/false default -> precision; }; } @Override public String getColumnLabel(int column) throws SQLException { return columnStrategy.getColumnLabel(getFieldDescriptor(column)); } @Override public String getColumnName(int column) throws SQLException { return columnStrategy.getColumnName(getFieldDescriptor(column)); } /** * {@inheritDoc} * * @return Always {@code ""} as schemas are not supported. */ @Override public String getSchemaName(int column) throws SQLException { return ""; } /** * {@inheritDoc} *

* NOTE For {@code NUMERIC} and {@code DECIMAL} we attempt to retrieve the exact precision from the metadata, * if this is not possible (eg the column is dynamically defined in the query), the reported precision is * the maximum precision allowed by the underlying storage data type. *

*/ @Override public int getPrecision(int column) throws SQLException { return getPrecisionInternal(column); } @Override public int getScale(int column) throws SQLException { return getScaleInternal(column); } @Override public String getTableName(int column) throws SQLException { String result = getFieldDescriptor(column).getOriginalTableName(); if (result == null) result = ""; return result; } @Override public String getTableAlias(int column) throws SQLException { String result = getFieldDescriptor(column).getTableAlias(); if (result == null) result = getTableName(column); return result; } /** * {@inheritDoc} * * @return Always {@code ""} as catalogs are not supported */ @Override public String getCatalogName(int column) throws SQLException { return ""; } @Override public int getColumnType(int column) throws SQLException { return getFieldType(column); } @Override public String getColumnTypeName(int column) throws SQLException { return getFieldTypeName(column); } /** * {@inheritDoc} *

* The current implementation always returns {@code false}, except for a DB_KEY column. *

*/ @Override public boolean isReadOnly(int column) throws SQLException { // TODO Need to consider privileges!! return getFieldDescriptor(column).isDbKey(); } /** * {@inheritDoc} *

* The current implementation always returns {@code true}, except for a DB_KEY column. *

*/ @Override public boolean isWritable(int column) throws SQLException { // TODO Needs privileges? return !getFieldDescriptor(column).isDbKey(); } @Override public boolean isDefinitelyWritable(int column) throws SQLException { return isWritable(column); } @Override public String getColumnClassName(int column) throws SQLException { return getFieldClassName(column); } private static final int FIELD_INFO_RELATION_NAME = 1; private static final int FIELD_INFO_FIELD_NAME = 2; private static final int FIELD_INFO_FIELD_PRECISION = 3; private static final int FIELD_INFO_FIELD_AUTO_INC = 4; private static final String GET_FIELD_INFO_25 = """ select RF.RDB$RELATION_NAME as RELATION_NAME, RF.RDB$FIELD_NAME as FIELD_NAME, F.RDB$FIELD_PRECISION as FIELD_PRECISION, 'F' as FIELD_AUTO_INC from RDB$RELATION_FIELDS RF inner join RDB$FIELDS F on RF.RDB$FIELD_SOURCE = F.RDB$FIELD_NAME where RF.RDB$FIELD_NAME = ? and RF.RDB$RELATION_NAME = ?"""; private static final String GET_FIELD_INFO_30 = """ select RF.RDB$RELATION_NAME as RELATION_NAME, RF.RDB$FIELD_NAME as FIELD_NAME, F.RDB$FIELD_PRECISION as FIELD_PRECISION, RF.RDB$IDENTITY_TYPE is not null as FIELD_AUTO_INC from RDB$RELATION_FIELDS RF inner join RDB$FIELDS F on RF.RDB$FIELD_SOURCE = F.RDB$FIELD_NAME where RF.RDB$FIELD_NAME = ? and RF.RDB$RELATION_NAME = ?"""; // Apparently there is a limit in the UNION. It is necessary to split in several queries. Although the problem // reported with 93 UNION, use only 70. private static final int MAX_FIELD_INFO_UNIONS = 70; @Override @SuppressWarnings({ "java:S1994", "java:S135" }) protected Map getExtendedFieldInfo(FBConnection connection) throws SQLException { if (connection == null || !connection.isExtendedMetadata()) return Collections.emptyMap(); final int fieldCount = getFieldCount(); int currentColumn = 1; var result = new HashMap(); FBDatabaseMetaData metaData = (FBDatabaseMetaData) connection.getMetaData(); var params = new ArrayList(); var sb = new StringBuilder(); boolean fb3OrHigher = metaData.getDatabaseMajorVersion() >= 3; String getFieldInfoQuery = fb3OrHigher ? GET_FIELD_INFO_30 : GET_FIELD_INFO_25; while (currentColumn <= fieldCount) { params.clear(); sb.setLength(0); for (int unionCount = 0; currentColumn <= fieldCount && unionCount < MAX_FIELD_INFO_UNIONS; currentColumn++) { FieldDescriptor fieldDescriptor = getFieldDescriptor(currentColumn); if (!needsExtendedFieldInfo(fieldDescriptor, fb3OrHigher)) continue; String relationName = fieldDescriptor.getOriginalTableName(); String fieldName = fieldDescriptor.getOriginalName(); if (isNullOrEmpty(relationName) || isNullOrEmpty(fieldName)) continue; if (unionCount != 0) { sb.append("\nunion all\n"); } sb.append(getFieldInfoQuery); params.add(fieldName); params.add(relationName); unionCount++; } if (sb.isEmpty()) continue; try (ResultSet rs = metaData.doQuery(sb.toString(), params, true)) { while (rs.next()) { ExtendedFieldInfo fieldInfo = extractExtendedFieldInfo(rs); result.put(fieldInfo.fieldKey(), fieldInfo); } } } return result; } private static ExtendedFieldInfo extractExtendedFieldInfo(ResultSet rs) throws SQLException { return new ExtendedFieldInfo(rs.getString(FIELD_INFO_RELATION_NAME), rs.getString(FIELD_INFO_FIELD_NAME), rs.getInt(FIELD_INFO_FIELD_PRECISION), rs.getBoolean(FIELD_INFO_FIELD_AUTO_INC)); } /** * @return {@code true} when the field descriptor needs extended field info (currently only NUMERIC and DECIMAL, * and - when {@code fb3OrHigher == true} - INTEGER, BIGINT and SMALLINT) */ private static boolean needsExtendedFieldInfo(FieldDescriptor fieldDescriptor, boolean fb3OrHigher) { return switch (JdbcTypeConverter.toJdbcType(fieldDescriptor)) { case Types.NUMERIC, Types.DECIMAL -> true; case Types.INTEGER, Types.BIGINT, Types.SMALLINT -> fb3OrHigher; default -> false; }; } /** * Strategy for retrieving column labels and column names */ private enum ColumnStrategy { /** * Default, JDBC-compliant, strategy for column naming. *

* columnLabel is the AS clause (xsqlvar.aliasname) if specified, * otherwise xsqlvar.sqlname. *

*

* columnName is xsqlvar.sqlname if specified, otherwise xsqlvar.aliasname (TODO: change this?) *

*/ DEFAULT { @Override String getColumnName(FieldDescriptor fieldDescriptor) { return fieldDescriptor.getOriginalName() != null ? fieldDescriptor.getOriginalName() : getColumnLabel(fieldDescriptor); } }, /** * Alternative strategy for column naming (related to columnLabelForName connection property) *

* This strategy is not JDBC-compliant, but is provided as a workaround for use with com.sun.rowset.CachedRowSetImpl and * for people expecting the old behavior. *

* columnLabel is the AS clause (xsqlvar.aliasname) if specified, * otherwise xsqlvar.sqlname. *

*

* columnName is identical to columnLabel. *

*/ COLUMN_LABEL_FOR_NAME { @Override String getColumnName(FieldDescriptor fieldDescriptor) { return getColumnLabel(fieldDescriptor); } }; /** * Retrieve the columnName for the specified column. * * @param fieldDescriptor * Column descriptor * @return value for the columnName */ abstract String getColumnName(FieldDescriptor fieldDescriptor); /** * Retrieve the columnLabel for the specified column. * * @param fieldDescriptor * Column descriptor * @return value for the columnLabel */ String getColumnLabel(FieldDescriptor fieldDescriptor) { if (fieldDescriptor.getFieldName() != null) { return fieldDescriptor.getFieldName(); } else if (fieldDescriptor.getOriginalName() != null) { return fieldDescriptor.getOriginalName(); } else { return ""; } } } }




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