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/* Copyright (c) 2001-2004, The HSQL Development Group
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * Neither the name of the HSQL Development Group nor the names of its
 * contributors may be used to endorse or promote products derived from this
 * software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL HSQL DEVELOPMENT GROUP, HSQLDB.ORG, 
 * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */


package org.hsqldb.jdbc;

import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.SQLWarning;

import org.hsqldb.HsqlException;
import org.hsqldb.Result;
import org.hsqldb.ResultConstants;
import org.hsqldb.Trace;
import org.hsqldb.Types;

// fredt@users 20020320 - patch 1.7.0 - JDBC 2 support and error trapping
// JDBC 2 methods can now be called from jdk 1.1.x - see javadoc comments
// SCROLL_INSENSITIVE and FORWARD_ONLY types for ResultSet are now supported
// boucherb@users 20020509 - added "throws SQLException" to all methods where
// it was missing here but specified in the java.sql.Statement interface,
// updated generic documentation to JDK 1.4, and added JDBC3 methods and docs
// boucherb@users and fredt@users - 20020505 extensive review and update
// of docs and behaviour to comply with java.sql specification
// fredt@users 20030620 - patch 1.7.2 - rewritten and simplified
// boucherb@users 200404xx - javadoc updates toward 1.7.2 final

/**
 * 
 * The object used for executing a static SQL statement
 * and returning the results it produces.
 * 

* By default, only one ResultSet object per Statement * object can be open at the same time. Therefore, if the reading of one * ResultSet object is interleaved * with the reading of another, each must have been generated by * different Statement objects. All execution methods in the * Statement interface implicitly close a statment's current * ResultSet object if an open one exists.

* * * *

*

HSQLDB-Specific Information:

* * JRE 1.1.x Notes:

* * In general, JDBC 2 support requires Java 1.2 and above, and JDBC3 requires * Java 1.4 and above. In HSQLDB, support for methods introduced in different * versions of JDBC depends on the JDK version used for compiling and building * HSQLDB.

* * Since 1.7.0, all JDBC 2 methods can be called while executing under the * version 1.1.x * Java Runtime EnvironmentTM. * However, in addition to this technique requiring explicit casts to the * org.hsqldb.jdbcXXX classes, some of these method calls require * int values that are defined only in the JDBC 2 or greater * version of the * * ResultSet interface. For this reason these values are * defined in {@link jdbcResultSet jdbcResultSet}.

* * In a JRE 1.1.x environment, calling JDBC 2 methods that take or return the * JDBC2-only ResultSet values can be achieved by referring * to them in parameter specifications and return value comparisons, * respectively, as follows:

* *

 * jdbcResultSet.FETCH_FORWARD
 * jdbcResultSet.TYPE_FORWARD_ONLY
 * jdbcResultSet.TYPE_SCROLL_INSENSITIVE
 * jdbcResultSet.CONCUR_READ_ONLY
 * //etc.
 * 

* * However, please note that code written to use HSQLDB JDBC 2 features under * JDK 1.1.x will not be compatible for use with other JDBC 2 drivers. Please * also note that this feature is offered solely as a convenience to developers * who must work under JDK 1.1.x due to operating constraints, yet wish to * use some of the more advanced features available under the JDBC 2 * specification.

* * (fredt@users)
* (boucherb@users)

* *

* * * @author boucherb@users * @author fredt@user * @version 1.7.2 * @see jdbcConnection#createStatement * @see jdbcResultSet */ public class jdbcStatement implements java.sql.Statement { /** * Whether this Statement has been explicitly closed. A jdbcConnection * object now explicitly closes all of its open jdbcXXXStatement objects * when it is closed. */ boolean isClosed; /** Is escape processing enabled? */ private boolean isEscapeProcessing = true; /** The connection used to execute this statement. */ protected jdbcConnection connection; /** The maximum number of rows to generate when executing this statement. */ protected int maxRows; /** The result of executing this statement. */ protected Result resultIn; /** The result set type obtained by executing this statement. */ protected int rsType = jdbcResultSet.TYPE_FORWARD_ONLY; /** Used by this statement to communicate non-batched requests. */ protected Result resultOut = new Result(ResultConstants.SQLEXECDIRECT); /** Use by this statement to communicate batched execution requests */ protected Result batchResultOut = null; // boucherb@users // NOTE: // This method is synchronized since resultIn is an instance attribute // and thus it is theoretically possible that a race condition occurs // in which a different thread executes fetchResult(sql), replacing // resultIn before it gets assigned propery to the new result set. // fredt - this class is not supposed to be called multi-threaded - // For example, if two threads call execute() then both call getResult() in // the wrong order, the ResultSet object for one call could actually belong // to the other call. /** * * Executes the given SQL statement, which returns a single * ResultSet object.

* * * @param sql an SQL statement to be sent to the database, typically a * static SQL SELECT statement * @return a ResultSet object that contains the data produced * by the given query; never null * @exception SQLException if a database access error occurs or the given * SQL statement produces anything other than a single * ResultSet object */ public ResultSet executeQuery(String sql) throws SQLException { checkClosed(); connection.clearWarningsNoCheck(); fetchResult(sql); return new jdbcResultSet(this, resultIn, connection.connProperties, connection.isNetConn); } /** * * Executes the given SQL statement, which may be an INSERT, * UPDATE, or DELETE statement or an * SQL statement that returns nothing, such as an SQL DDL statement.

* * * @param sql an SQL INSERT, UPDATE or * DELETE statement or an SQL statement that returns nothing * @return either the row count for INSERT, UPDATE * or DELETE statements, or 0 for SQL statements * that return nothing * @exception SQLException if a database access error occurs or the given * SQL statement produces a ResultSet object */ public int executeUpdate(String sql) throws SQLException { checkClosed(); connection.clearWarningsNoCheck(); fetchResult(sql); if (resultIn == null || resultIn.iMode == ResultConstants.DATA) { /** * @todo: - fredt@users - check for type of statement _must_ be done * in the engine and error returned _without_ executing */ throw new SQLException( Trace.getMessage(Trace.jdbcStatement_executeUpdate)); } else if (resultIn.iMode == ResultConstants.ERROR) { jdbcUtil.throwError(resultIn); } return resultIn.getUpdateCount(); } /** * * Releases this Statement object's database * and JDBC resources immediately instead of waiting for * this to happen when it is automatically closed. * It is generally good practice to release resources as soon as * you are finished with them to avoid tying up database * resources. *

* Calling the method close on a Statement * object that is already closed has no effect. *

* Note: A Statement object is automatically closed * when it is garbage collected. When a Statement object is * closed, its current ResultSet object, if one exists, is * also closed.

* * * @exception SQLException if a database access error occurs */ public void close() throws SQLException { if (isClosed) { return; } batchResultOut = null; connection = null; resultIn = null; resultOut = null; isClosed = true; } //---------------------------------------------------------------------- /** * * Retrieves the maximum number of bytes that can be * returned for character and binary column values in a ResultSet * object produced by this Statement object. * This limit applies only to BINARY, * VARBINARY, LONGVARBINARY, CHAR, * VARCHAR, and LONGVARCHAR * columns. If the limit is exceeded, the excess data is silently * discarded.

* * * *

*

HSQLDB-Specific Information:

* * Including 1.7.2, HSQLDB always returns zero, meaning there * is no limit. *

* * * @return the current column size limit for columns storing character and * binary values; zero means there is no limit * @exception SQLException if a database access error occurs * @see #setMaxFieldSize */ public int getMaxFieldSize() throws SQLException { checkClosed(); return 0; } /** * * Sets the limit for the maximum number of bytes in a ResultSet * column storing character or binary values to * the given number of bytes. This limit applies * only to BINARY, VARBINARY, * LONGVARBINARY, CHAR, VARCHAR, and * LONGVARCHAR fields. If the limit is exceeded, the excess data * is silently discarded. For maximum portability, use values * greater than 256.

* * * *

*

HSQLDB-Specific Information:

* * Including 1.7.2, calls to this method are simply ignored; HSQLDB always * stores the full number of bytes when dealing with any of the field types * mentioned above. These types all have an absolute maximum element upper * bound determined by the Java array index limit * java.lang.Integer.MAX_VALUE. For XXXBINARY types, this translates to * Integer.MAX_VALUE bytes. For XXXCHAR types, this translates to * 2 * Integer.MAX_VALUE bytes (2 bytes / character) *

* * * @param max the new column size limit in bytes; zero means there is no limit * @exception SQLException if a database access error occurs * or the condition max >= 0 is not satisfied * @see #getMaxFieldSize */ public void setMaxFieldSize(int max) throws SQLException { checkClosed(); if (max < 0) { throw jdbcUtil.sqlException(Trace.INVALID_JDBC_ARGUMENT); } } /** * * Retrieves the maximum number of rows that a * ResultSet object produced by this * Statement object can contain. If this limit is exceeded, * the excess rows are silently dropped.

* * * @return the current maximum number of rows for a ResultSet * object produced by this Statement object; * zero means there is no limit * @exception SQLException if a database access error occurs * @see #setMaxRows */ public int getMaxRows() throws SQLException { checkClosed(); return maxRows; } /** * * Sets the limit for the maximum number of rows that any * ResultSet object can contain to the given number. * If the limit is exceeded, the excess * rows are silently dropped.

* * * @param max the new max rows limit; zero means there is no limit * @exception SQLException if a database access error occurs * or the condition max >= 0 is not satisfied * @see #getMaxRows */ public void setMaxRows(int max) throws SQLException { checkClosed(); if (max < 0) { throw jdbcUtil.sqlException(Trace.INVALID_JDBC_ARGUMENT); } maxRows = max; } /** * * Sets escape processing on or off. * If escape scanning is on (the default), the driver will do * escape substitution before sending the SQL statement to the database. * * Note: Since prepared statements have usually been parsed prior * to making this call, disabling escape processing for * PreparedStatements objects will have no effect.

* * * @param enable true to enable escape processing; * false to disable it * @exception SQLException if a database access error occurs */ public void setEscapeProcessing(boolean enable) throws SQLException { checkClosed(); isEscapeProcessing = enable; } /** * * Retrieves the number of seconds the driver will * wait for a Statement object to execute. If the * limit is exceeded, an SQLException is thrown.

* * * *

*

HSQLDB-Specific Information:

* * Including 1.7.2, HSQLDB always returns zero, meaning there * is no limit. *

* * * @return the current query timeout limit in seconds; zero means there is * no limit * @exception SQLException if a database access error occurs * @see #setQueryTimeout */ public int getQueryTimeout() throws SQLException { checkClosed(); return 0; } /** * * Sets the number of seconds the driver will wait for a * Statement object to execute to the given number of seconds. * If the limit is exceeded, an SQLException is thrown.

* * * *

*

HSQLDB-Specific Information:

* * Including 1.7.2, calls to this method are ignored; HSQLDB waits an * unlimited amount of time for statement execution * requests to return. *

* * * @param seconds the new query timeout limit in seconds; zero means * there is no limit * @exception SQLException if a database access error occurs * or the condition seconds >= 0 is not satisfied * @see #getQueryTimeout */ public void setQueryTimeout(int seconds) throws SQLException { checkClosed(); if (seconds < 0) { throw jdbcUtil.sqlException(Trace.INVALID_JDBC_ARGUMENT); } } /** * * Cancels this Statement object if both the DBMS and * driver support aborting an SQL statement. * This method can be used by one thread to cancel a statement that * is being executed by another thread.

* * * *

*

HSQLDB-Specific Information:

* * Including 1.7.2, HSQLDB does not support aborting a SQL * statement; calls to this method are ignored. *

* * * @exception SQLException if a database access error occurs */ public void cancel() throws SQLException { checkClosed(); } /** * * Retrieves the first warning reported by calls on this Statement object. * Subsequent Statement object warnings will be chained to this * SQLWarning object. * *

The warning chain is automatically cleared each time * a statement is (re)executed. This method may not be called on a closed * Statement object; doing so will cause an SQLException * to be thrown. * *

Note: If you are processing a ResultSet object, any * warnings associated with reads on that ResultSet object * will be chained on it rather than on the Statement * object that produced it.

* * * *

*

HSQLDB-Specific Information:

* * Including 1.7.2, HSQLDB never produces Statement warnings; * this method always returns null. *

* * * @return the first SQLWarning object or null * if there are no warnings * @exception SQLException if a database access error occurs or this * method is called on a closed statement */ public SQLWarning getWarnings() throws SQLException { checkClosed(); return null; } /** * * Clears all the warnings reported on this Statement * object. After a call to this method, * the method getWarnings will return * null until a new warning is reported for this * Statement object.

* * * *

*

HSQLDB-Specific Information:

* * Including HSQLDB 1.7.2, SQLWarning objects are * never produced for Statement Objects; calls to this method are * ignored. *

* * * @exception SQLException if a database access error occurs */ public void clearWarnings() throws SQLException { checkClosed(); } /** * * Sets the SQL cursor name to the given String, which * will be used by subsequent Statement object * execute methods. This name can then be * used in SQL positioned update or delete statements to identify the * current row in the ResultSet object generated by this * statement. If the database does not support positioned update/delete, * this method is a noop. To insure that a cursor has the proper isolation * level to support updates, the cursor's SELECT statement * should have the form SELECT FOR UPDATE. If * FOR UPDATE is not present, positioned updates may fail. * *

Note: By definition, the execution of positioned updates and * deletes must be done by a different Statement object than * the one that generated the ResultSet object being used for * positioning. Also, cursor names must be unique within a connection.

* * * *

*

HSQLDB-Specific Information:

* * Including 1.7.2, HSQLDB does not support named cursors, * updateable results or table locking via SELECT FOR UPDATE; * calls to this method are ignored. *

* * * @param name the new cursor name, which must be unique within * a connection * @exception SQLException if a database access error occurs */ public void setCursorName(String name) throws SQLException { checkClosed(); } //----------------------- Multiple Results -------------------------- /** * * Executes the given SQL statement, which may return multiple results. * In some (uncommon) situations, a single SQL statement may return * multiple result sets and/or update counts. Normally you can ignore * this unless you are (1) executing a stored procedure that you know may * return multiple results or (2) you are dynamically executing an * unknown SQL string. *

* The execute method executes an SQL statement and indicates the * form of the first result. You must then use the methods * getResultSet or getUpdateCount * to retrieve the result, and getMoreResults to * move to any subsequent result(s).

* * * @param sql any SQL statement * @return true if the first result is a ResultSet * object; false if it is an update count or there are * no results * @exception SQLException if a database access error occurs * @see #getResultSet * @see #getUpdateCount * @see #getMoreResults */ public boolean execute(String sql) throws SQLException { checkClosed(); connection.clearWarningsNoCheck(); fetchResult(sql); return resultIn.iMode == ResultConstants.DATA; } /** * * Retrieves the current result as a ResultSet object. * This method should be called only once per result.

* * * *

*

HSQLDB-Specific Information:

* * Without an interceding call to executeXXX, each invocation of this * method will produce a new, initialized ResultSet instance referring to * the current result, if any. *

* * * @return the current result as a ResultSet object or * null if the result is an update count or there * are no more results * @exception SQLException if a database access error occurs * @see #execute */ public ResultSet getResultSet() throws SQLException { checkClosed(); return resultIn == null || resultIn.iMode != ResultConstants.DATA ? null : new jdbcResultSet(this, resultIn, connection.connProperties, connection.isNetConn); } /** * * Retrieves the current result as an update count; * if the result is a ResultSet object or there are no more results, -1 * is returned. This method should be called only once per result.

* * * @return the current result as an update count; -1 if the current result is a * ResultSet object or there are no more results * @exception SQLException if a database access error occurs * @see #execute */ public int getUpdateCount() throws SQLException { // fredt - omit checkClosed() in order to be able to handle the result of a // SHUTDOWN query // checkClosed(); return (resultIn == null || resultIn.iMode == ResultConstants.DATA) ? -1 : resultIn.getUpdateCount(); } /** * * Moves to this Statement object's next result, returns * true if it is a ResultSet object, and * implicitly closes any current ResultSet * object(s) obtained with the method getResultSet. * *

There are no more results when the following is true: *

     *    (!getMoreResults() && (getUpdateCount() == -1)
     * 

* * * @return true if the next result is a ResultSet * object; false if it is an update count or there are * no more results * @exception SQLException if a database access error occurs * @see #execute */ public boolean getMoreResults() throws SQLException { checkClosed(); resultIn = null; return false; } //--------------------------JDBC 2.0----------------------------- /** * * Gives the driver a hint as to the direction in which * rows will be processed in ResultSet * objects created using this Statement object. The * default value is ResultSet.FETCH_FORWARD. *

* Note that this method sets the default fetch direction for * result sets generated by this Statement object. * Each result set has its own methods for getting and setting * its own fetch direction.

* * * *

*

HSQLDB-Specific Information:

* * Including 1.7.2, HSQLDB supports only FETCH_FORWARD.

* * Setting any other value will throw an SQLException * stating that the operation is not supported. *

* * * @param direction the initial direction for processing rows * @exception SQLException if a database access error occurs * or the given direction * is not one of ResultSet.FETCH_FORWARD, * ResultSet.FETCH_REVERSE, or * ResultSet.FETCH_UNKNOWN

* * HSQLDB throws for all values except FETCH_FORWARD * @since JDK 1.2 (JDK 1.1.x developers: read the new overview * for jdbcStatement) * @see #getFetchDirection */ public void setFetchDirection(int direction) throws SQLException { checkClosed(); if (direction != jdbcResultSet.FETCH_FORWARD) { throw jdbcUtil.notSupported; } } /** * * Retrieves the direction for fetching rows from * database tables that is the default for result sets * generated from this Statement object. * If this Statement object has not set * a fetch direction by calling the method setFetchDirection, * the return value is implementation-specific.

* * * *

*

HSQLDB-Specific Information:

* * Including 1.7.2, HSQLDB always returns FETCH_FORWARD. *

* * * @return the default fetch direction for result sets generated * from this Statement object * @exception SQLException if a database access error occurs * @since JDK 1.2 (JDK 1.1.x developers: read the new overview * for jdbcStatement) * @see #setFetchDirection */ public int getFetchDirection() throws SQLException { checkClosed(); return jdbcResultSet.FETCH_FORWARD; } /** * * Gives the JDBC driver a hint as to the number of rows that should * be fetched from the database when more rows are needed. The number * of rows specified affects only result sets created using this * statement. If the value specified is zero, then the hint is ignored. * The default value is zero.

* * * *

*

HSQLDB-Specific Information:

* * Including 1.7.2, calls to this method are ignored; * HSQLDB fetches each result completely as part of * executing its statement. *

* * * @param rows the number of rows to fetch * @exception SQLException if a database access error occurs, or the * condition 0 <= rows <= this.getMaxRows() * is not satisfied.

* * HSQLDB never throws an exception, since calls to this method * are always ignored. * @since JDK 1.2 (JDK 1.1.x developers: read the new overview * for jdbcStatement) * @see #getFetchSize */ public void setFetchSize(int rows) throws SQLException { checkClosed(); } /** * * Retrieves the number of result set rows that is the default * fetch size for ResultSet objects * generated from this Statement object. * If this Statement object has not set * a fetch size by calling the method setFetchSize, * the return value is implementation-specific.

* * * *

* HSQLDB-Specific Information

* * Including 1.7.2, this method always returns 0. * HSQLDB fetches each result completely as part of * executing its statement *

* * * @return the default fetch size for result sets generated * from this Statement object * @exception SQLException if a database access error occurs * @since JDK 1.2 (JDK 1.1.x developers: read the new overview * for jdbcStatement) * @see #setFetchSize */ public int getFetchSize() throws SQLException { checkClosed(); return 0; } /** * * Retrieves the result set concurrency for ResultSet objects * generated by this Statement object.

* * * *

*

HSQLDB-Specific Information:

* * Including 1.7.2, HSQLDB supports only * CONCUR_READ_ONLY concurrency. *

* * * @return either ResultSet.CONCUR_READ_ONLY or * ResultSet.CONCUR_UPDATABLE (not supported) * @exception SQLException if a database access error occurs * @since JDK 1.2 (JDK 1.1.x developers: read the new overview * for jdbcStatement) */ public int getResultSetConcurrency() throws SQLException { checkClosed(); return jdbcResultSet.CONCUR_READ_ONLY; } /** * * Retrieves the result set type for ResultSet objects * generated by this Statement object.

* * * *

*

HSQLDB-Specific Information:

* * HSQLDB 1.7.0 and later versions support TYPE_FORWARD_ONLY * and TYPE_SCROLL_INSENSITIVE. *

* * * @return one of ResultSet.TYPE_FORWARD_ONLY, * ResultSet.TYPE_SCROLL_INSENSITIVE, or * ResultSet.TYPE_SCROLL_SENSITIVE (not supported)

* * Note: Up to and including 1.7.1, HSQLDB never returns * TYPE_SCROLL_SENSITIVE * @exception SQLException if a database access error occurs * @since JDK 1.2 (JDK 1.1.x developers: read the new overview * for jdbcStatement) */ public int getResultSetType() throws SQLException { // fredt - omit checkClosed() in order to be able to handle the result of a // SHUTDOWN query // checkClosed(); return rsType; } /** * * Adds the given SQL command to the current list of commmands for this * Statement object. The commands in this list can be * executed as a batch by calling the method executeBatch. *

* NOTE: This method is optional.

* * * *

*

HSQLDB-Specific Information:

* * Starting with 1.7.2, this feature is supported. *

* * * @param sql typically this is a static SQL INSERT or * UPDATE statement * @exception SQLException if a database access error occurs, or the * driver does not support batch updates * @see #executeBatch * @since JDK 1.2 (JDK 1.1.x developers: read the new overview * for jdbcStatement) */ public void addBatch(String sql) throws SQLException { checkClosed(); if (isEscapeProcessing) { sql = connection.nativeSQL(sql); } if (batchResultOut == null) { batchResultOut = new Result(ResultConstants.BATCHEXECDIRECT, new int[]{ Types.VARCHAR }, 0); } batchResultOut.add(new Object[]{ sql }); } /** * * Empties this Statement object's current list of * SQL commands. *

* NOTE: This method is optional.

* * * *

*

HSQLDB-Specific Information:

* * Starting with HSQLDB 1.7.2, this feature is supported. *

* * * @exception SQLException if a database access error occurs or the * driver does not support batch updates * @see #addBatch * @since JDK 1.2 (JDK 1.1.x developers: read the new overview * for jdbcStatement) */ public void clearBatch() throws SQLException { checkClosed(); if (batchResultOut != null) { batchResultOut.clear(); } } /** * * Submits a batch of commands to the database for execution and * if all commands execute successfully, returns an array of update counts. * The int elements of the array that is returned are ordered * to correspond to the commands in the batch, which are ordered * according to the order in which they were added to the batch. * The elements in the array returned by the method executeBatch * may be one of the following: *
    *
  1. A number greater than or equal to zero -- indicates that the * command was processed successfully and is an update count giving the * number of rows in the database that were affected by the command's * execution *
  2. A value of SUCCESS_NO_INFO -- indicates that the command was * processed successfully but that the number of rows affected is * unknown *

    * If one of the commands in a batch update fails to execute properly, * this method throws a BatchUpdateException, and a JDBC * driver may or may not continue to process the remaining commands in * the batch. However, the driver's behavior must be consistent with a * particular DBMS, either always continuing to process commands or never * continuing to process commands. If the driver continues processing * after a failure, the array returned by the method * BatchUpdateException.getUpdateCounts * will contain as many elements as there are commands in the batch, and * at least one of the elements will be the following: *

    *

  3. A value of EXECUTE_FAILED -- indicates that the command failed * to execute successfully and occurs only if a driver continues to * process commands after a command fails *
*

* A driver is not required to implement this method. * The possible implementations and return values have been modified in * the Java 2 SDK, Standard Edition, version 1.3 to * accommodate the option of continuing to proccess commands in a batch * update after a BatchUpdateException obejct has been thrown.

* * * *

*

HSQLDB-Specific Information:

* * Starting with HSQLDB 1.7.2, this feature is supported.

* * HSQLDB stops execution of commands in a batch when one of the commands * results in an exception. The size of the returned array equals the * number of commands that were executed successfully.

* * When the product is built under the JAVA1 target, an exception * is never thrown and it is the responsibility of the client software to * check the size of the returned update count array to determine if any * batch items failed. To build and run under the JAVA2 target, JDK/JRE * 1.3 or higher must be used. *

* * * @return an array of update counts containing one element for each * command in the batch. The elements of the array are ordered according * to the order in which commands were added to the batch. * @exception SQLException if a database access error occurs or the * driver does not support batch statements. Throws * {@link java.sql.BatchUpdateException} * (a subclass of java.sql.SQLException) if one of the commands * sent to the database fails to execute properly or attempts to return a * result set. * @since JDK 1.3 (JDK 1.1.x developers: read the new overview * for jdbcStatement) */ public int[] executeBatch() throws SQLException { int[] updateCounts; int batchCount; HsqlException he; checkClosed(); connection.clearWarningsNoCheck(); if (batchResultOut == null) { batchResultOut = new Result(ResultConstants.BATCHEXECDIRECT, new int[]{ Types.VARCHAR }, 0); } batchCount = batchResultOut.getSize(); try { resultIn = connection.sessionProxy.execute(batchResultOut); } catch (HsqlException e) { batchResultOut.clear(); throw jdbcUtil.sqlException(e); } batchResultOut.clear(); if (resultIn.iMode == ResultConstants.ERROR) { jdbcUtil.throwError(resultIn); } updateCounts = resultIn.getUpdateCounts(); //#ifdef JAVA2 if (updateCounts.length != batchCount) { throw new java.sql.BatchUpdateException("failed batch", updateCounts); } //#endif JAVA2 return updateCounts; } /** * * Retrieves the Connection object * that produced this Statement object.

* * * @return the connection that produced this statement * @exception SQLException if a database access error occurs * @since JDK 1.2 (JDK 1.1.x developers: read the new overview * for jdbcStatement) */ public Connection getConnection() throws SQLException { checkClosed(); return connection; } //--------------------------JDBC 3.0----------------------------- /** * * Moves to this Statement object's next result, deals with * any current ResultSet object(s) according to the instructions * specified by the given flag, and returns * true if the next result is a ResultSet object. * *

There are no more results when the following is true: *

     *   (!getMoreResults() && (getUpdateCount() == -1)
     * 

* * * *

*

HSQLDB-Specific Information:

* * HSQLDB 1.7.2 does not support this feature.

* * Calling this method always throws an SQLException, * stating that the function is not supported. *

* * * @param current one of the following Statement * constants indicating what should happen to current * ResultSet objects obtained using the method * getResultSetCLOSE_CURRENT_RESULT, * KEEP_CURRENT_RESULT, or * CLOSE_ALL_RESULTS * @return true if the next result is a ResultSet * object; false if it is an update count or there are no * more results * @exception SQLException if a database access error occurs * @since JDK 1.4, HSQLDB 1.7 * @see #execute */ //#ifdef JDBC3 public boolean getMoreResults(int current) throws SQLException { throw jdbcUtil.notSupported; } //#endif JDBC3 /** * * Retrieves any auto-generated keys created as a result of executing this * Statement object. If this Statement object did * not generate any keys, an empty ResultSet * object is returned.

* * * *

*

HSQLDB-Specific Information:

* * HSQLDB 1.7.2 does not support this feature.

* * Calling this method always throws an SQLException, * stating that the function is not supported. *

* * * @return a ResultSet object containing the auto-generated key(s) * generated by the execution of this Statement object * @exception SQLException if a database access error occurs * @since JDK 1.4, HSQLDB 1.7 */ //#ifdef JDBC3 public ResultSet getGeneratedKeys() throws SQLException { throw jdbcUtil.notSupported; } //#endif JDBC3 /** * * Executes the given SQL statement and signals the driver with the * given flag about whether the * auto-generated keys produced by this Statement object * should be made available for retrieval.

* * * *

*

HSQLDB-Specific Information:

* * HSQLDB 1.7.2 does not support this feature.

* * Calling this method always throws an SQLException, * stating that the function is not supported. *

* * * @param sql must be an SQL INSERT, UPDATE or * DELETE statement or an SQL statement that * returns nothing * @param autoGeneratedKeys a flag indicating whether auto-generated keys * should be made available for retrieval; * one of the following constants: * Statement.RETURN_GENERATED_KEYS * Statement.NO_GENERATED_KEYS * @return either the row count for INSERT, UPDATE * or DELETE statements, or 0 for SQL * statements that return nothing * @exception SQLException if a database access error occurs, the given * SQL statement returns a ResultSet object, or * the given constant is not one of those allowed * @since JDK 1.4, HSQLDB 1.7 */ //#ifdef JDBC3 public int executeUpdate(String sql, int autoGeneratedKeys) throws SQLException { throw jdbcUtil.notSupported; } //#endif JDBC3 /** * * Executes the given SQL statement and signals the driver that the * auto-generated keys indicated in the given array should be made available * for retrieval. The driver will ignore the array if the SQL statement * is not an INSERT statement.

* * * *

*

HSQLDB-Specific Information:

* * HSQLDB 1.7.2 does not support this feature.

* * Calling this method always throws an SQLException, * stating that the function is not supported. *

* * * @param sql an SQL INSERT, UPDATE or * DELETE statement or an SQL statement that returns nothing, * such as an SQL DDL statement * @param columnIndexes an array of column indexes indicating the columns * that should be returned from the inserted row * @return either the row count for INSERT, UPDATE, * or DELETE statements, or 0 for SQL statements * that return nothing * @exception SQLException if a database access error occurs or the SQL * statement returns a ResultSet object * @since JDK 1.4, HSQLDB 1.7 */ //#ifdef JDBC3 public int executeUpdate(String sql, int columnIndexes[]) throws SQLException { throw jdbcUtil.notSupported; } //#endif JDBC3 /** * * Executes the given SQL statement and signals the driver that the * auto-generated keys indicated in the given array should be made available * for retrieval. The driver will ignore the array if the SQL statement * is not an INSERT statement.

* * * *

*

HSQLDB-Specific Information:

* * HSQLDB 1.7.2 does not support this feature.

* * Calling this method always throws an SQLException, * stating that the function is not supported. *

* * * @param sql an SQL INSERT, UPDATE or * DELETE statement or an SQL statement that returns nothing * @param columnNames an array of the names of the columns that should be * returned from the inserted row * @return either the row count for INSERT, UPDATE, * or DELETE statements, or 0 for SQL statements * that return nothing * @exception SQLException if a database access error occurs * @since JDK 1.4, HSQLDB 1.7 */ //#ifdef JDBC3 public int executeUpdate(String sql, String columnNames[]) throws SQLException { throw jdbcUtil.notSupported; } //#endif JDBC3 /** * * Executes the given SQL statement, which may return multiple results, * and signals the driver that any * auto-generated keys should be made available * for retrieval. The driver will ignore this signal if the SQL statement * is not an INSERT statement. *

* In some (uncommon) situations, a single SQL statement may return * multiple result sets and/or update counts. Normally you can ignore * this unless you are (1) executing a stored procedure that you know may * return multiple results or (2) you are dynamically executing an * unknown SQL string. *

* The execute method executes an SQL statement and indicates the * form of the first result. You must then use the methods * getResultSet or getUpdateCount * to retrieve the result, and getMoreResults to * move to any subsequent result(s).

* * * *

*

HSQLDB-Specific Information:

* * HSQLDB 1.7.2 does not support this feature.

* * Calling this method always throws an SQLException, * stating that the function is not supported. *

* * * @param sql any SQL statement * @param autoGeneratedKeys a constant indicating whether auto-generated * keys should be made available for retrieval using the method * getGeneratedKeys; one of the following constants: * Statement.RETURN_GENERATED_KEYS or * Statement.NO_GENERATED_KEYS * @return true if the first result is a ResultSet * object; false if it is an update count or there are * no results * @exception SQLException if a database access error occurs * @see #getResultSet * @see #getUpdateCount * @see #getMoreResults * @see #getGeneratedKeys * @since JDK 1.4, HSQLDB 1.7 */ //#ifdef JDBC3 public boolean execute(String sql, int autoGeneratedKeys) throws SQLException { throw jdbcUtil.notSupported; } //#endif JDBC3 /** * * Executes the given SQL statement, which may return multiple results, * and signals the driver that the * auto-generated keys indicated in the given array should be made available * for retrieval. This array contains the indexes of the columns in the * target table that contain the auto-generated keys that should be made * available. The driver will ignore the array if the given SQL statement * is not an INSERT statement. *

* Under some (uncommon) situations, a single SQL statement may return * multiple result sets and/or update counts. Normally you can ignore * this unless you are (1) executing a stored procedure that you know may * return multiple results or (2) you are dynamically executing an * unknown SQL string. *

* The execute method executes an SQL statement and indicates the * form of the first result. You must then use the methods * getResultSet or getUpdateCount * to retrieve the result, and getMoreResults to * move to any subsequent result(s).

* * * *

*

HSQLDB-Specific Information:

* * HSQLDB 1.7.2 does not support this feature.

* * Calling this method always throws an SQLException, * stating that the function is not supported. *

* * * @param sql any SQL statement * @param columnIndexes an array of the indexes of the columns in the * inserted row that should be made available for retrieval by a * call to the method getGeneratedKeys * @return true if the first result is a ResultSet * object; false if it is an update count or there * are no results * @exception SQLException if a database access error occurs * @see #getResultSet * @see #getUpdateCount * @see #getMoreResults * @since JDK 1.4, HSQLDB 1.7 */ //#ifdef JDBC3 public boolean execute(String sql, int columnIndexes[]) throws SQLException { throw jdbcUtil.notSupported; } //#endif JDBC3 /** * * Executes the given SQL statement, which may return multiple results, * and signals the driver that the * auto-generated keys indicated in the given array should be made available * for retrieval. This array contains the names of the columns in the * target table that contain the auto-generated keys that should be made * available. The driver will ignore the array if the given SQL statement * is not an INSERT statement. *

* In some (uncommon) situations, a single SQL statement may return * multiple result sets and/or update counts. Normally you can ignore * this unless you are (1) executing a stored procedure that you know may * return multiple results or (2) you are dynamically executing an * unknown SQL string. *

* The execute method executes an SQL statement and indicates the * form of the first result. You must then use the methods * getResultSet or getUpdateCount * to retrieve the result, and getMoreResults to * move to any subsequent result(s).

* * * *

*

HSQLDB-Specific Information:

* * HSQLDB 1.7.2 does not support this feature.

* * Calling this method always throws an SQLException, * stating that the function is not supported. *

* * * @param sql any SQL statement * @param columnNames an array of the names of the columns in the inserted * row that should be made available for retrieval by a call to the * method getGeneratedKeys * @return true if the next result is a ResultSet * object; false if it is an update count or there * are no more results * @exception SQLException if a database access error occurs * @see #getResultSet * @see #getUpdateCount * @see #getMoreResults * @see #getGeneratedKeys * @since JDK 1.4, HSQLDB 1.7 */ //#ifdef JDBC3 public boolean execute(String sql, String columnNames[]) throws SQLException { throw jdbcUtil.notSupported; } //#endif JDBC3 /** * * Retrieves the result set holdability for ResultSet objects * generated by this Statement object.

* * * *

*

HSQLDB-Specific Information:

* * Starting with 1.7.2, this method returns HOLD_CURSORS_OVER_COMMIT *

* * * @return either ResultSet.HOLD_CURSORS_OVER_COMMIT or * ResultSet.CLOSE_CURSORS_AT_COMMIT * @exception SQLException if a database access error occurs * @since JDK 1.4, HSQLDB 1.7 */ //#ifdef JDBC3 public int getResultSetHoldability() throws SQLException { return jdbcResultSet.HOLD_CURSORS_OVER_COMMIT; } //#endif JDBC3 // -------------------- Internal Implementation ---------------------------- /** * Constructs a new jdbcStatement with the specified connection and * result type. * * @param c the connection on which this statement will execute * @param type the kind of results this will return */ jdbcStatement(jdbcConnection c, int type) { // PRE: assume connection is not null and is not closed // PRE: assume type is a valid result set type code connection = c; rsType = type; } /** * Retrieves whether this statement is closed. */ boolean isClosed() { return isClosed; } /** * An internal check for closed statements. * * @throws SQLException when the connection is closed */ void checkClosed() throws SQLException { if (isClosed) { throw jdbcUtil.sqlException(Trace.STATEMENT_IS_CLOSED); } if (connection.isClosed) { throw jdbcUtil.sqlException(Trace.CONNECTION_IS_CLOSED); } } /** * Internal result producer for jdbcStatement (sqlExecDirect mode).

* * @param sql a character sequence representing the SQL to be executed * @throws SQLException when a database access error occurs */ private void fetchResult(String sql) throws SQLException { if (isEscapeProcessing) { sql = connection.nativeSQL(sql); } resultIn = null; resultOut.setMainString(sql); resultOut.setMaxRows(maxRows); try { resultIn = connection.sessionProxy.execute(resultOut); if (resultIn.iMode == ResultConstants.ERROR) { throw new HsqlException(resultIn); } } catch (HsqlException e) { throw jdbcUtil.sqlException(e); } } }




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