jdbctemplate.java

Java/J2EE application framework based on [Expert One-on-One J2EE Design and Development] by Rod John

	}

	/**
	 * Extract output parameters from the completed stored procedure.
	 * @param cs JDBC wrapper for the stored procedure
	 * @param parameters parameter list for the stored procedure
	 * @return parameters to the stored procedure
	 * @return Map that contains returned results
	 */
	protected Map extractOutputParameters(CallableStatement cs, List parameters) throws SQLException {
		Map returnedResults = new HashMap();
		int sqlColIndex = 1;
		for (int i = 0; i < parameters.size(); i++) {
			Object param = parameters.get(i);
			if (param instanceof SqlOutParameter) {
				SqlOutParameter outParam = (SqlOutParameter) param;
				if (outParam.isReturnTypeSupported()) {
					Object out = outParam.getSqlReturnType().getTypeValue(cs, sqlColIndex, outParam.getSqlType(), outParam.getTypeName());
					returnedResults.put(outParam.getName(), out);
				}
				else {
					Object out = cs.getObject(sqlColIndex);
					if (out instanceof ResultSet) {
						if (outParam.isResultSetSupported()) {
							returnedResults.putAll(processResultSet((ResultSet) out, outParam));
						}
						else {
							logger.warn("ResultSet returned from stored procedure but a corresponding " +
													"SqlOutParameter with a RowCallbackHandler was not declared");
							returnedResults.put(outParam.getName(), "ResultSet was returned but not processed.");
						}
					}
					else {
						returnedResults.put(outParam.getName(), out);
					}
				}
			}
			if (!(param instanceof SqlReturnResultSet)) {
				sqlColIndex++;
			}
		}
		return returnedResults;
	}

	/**
	 * Process the given ResultSet from a stored procedure.
	 * @param rs the ResultSet to process
	 * @param param the corresponding stored procedure parameter
	 * @return Map that contains returned results
	 */
	protected Map processResultSet(ResultSet rs, ResultSetSupportingSqlParameter param) throws SQLException {
		Map returnedResults = new HashMap();
		try {
			ResultSet rsToUse = rs;
			if (this.nativeJdbcExtractor != null) {
				rsToUse = this.nativeJdbcExtractor.getNativeResultSet(rs);
			}
			if (param.isRowCallbackHandlerSupported()) {
				// It's a RowCallbackHandler or RowMapper.
				// We'll get a RowCallbackHandler to use in both cases.
				RowCallbackHandler rch = param.getRowCallbackHandler();
				(new RowCallbackHandlerResultSetExtractor(rch)).extractData(rsToUse);
				if (rch instanceof ResultReader) {
					returnedResults.put(param.getName(), ((ResultReader) rch).getResults());
				}
				else {
					returnedResults.put(param.getName(), "ResultSet returned from stored procedure was processed.");
				}
			}
			else {
				// It's a ResultSetExtractor - simply apply it.
				Object result = param.getResultSetExtractor().extractData(rsToUse);
				returnedResults.put(param.getName(), result);
			}
		}
		finally {
			JdbcUtils.closeResultSet(rs);
		}
		return returnedResults;
	}


	/**
	 * Throw an SQLWarningException if we're not ignoring warnings.
	 * @param warning warning from current statement. May be null,
	 * in which case this method does nothing.
	 */
	private void throwExceptionOnWarningIfNotIgnoringWarnings(SQLWarning warning) throws SQLWarningException {
		if (warning != null) {
			if (this.ignoreWarnings) {
				logger.warn("SQLWarning ignored: " + warning);
			}
			else {
				throw new SQLWarningException("Warning not ignored", warning);
			}
		}
	}

	/**
	 * Determine SQL from potential provider object.
	 * @param sqlProvider object that's potentially a SqlProvider
	 * @return the SQL string, or null
	 * @see SqlProvider
	 */
	private String getSql(Object sqlProvider) {
		if (sqlProvider instanceof SqlProvider) {
			return ((SqlProvider) sqlProvider).getSql();
		}
		else {
			return null;
		}
	}


	/**
	 * Simple adapter for PreparedStatementCreator, allowing to use a plain SQL statement.
	 */
	private static class SimplePreparedStatementCreator
			implements PreparedStatementCreator, SqlProvider {

		private final String sql;

		public SimplePreparedStatementCreator(String sql) {
			this.sql = sql;
		}

		public PreparedStatement createPreparedStatement(Connection con) throws SQLException {
			return con.prepareStatement(this.sql);
		}

		public String getSql() {
			return sql;
		}
	}


	/**
	 * Simple adapter for CallableStatementCreator, allowing to use a plain SQL statement.
	 */
	private static class SimpleCallableStatementCreator
			implements CallableStatementCreator, SqlProvider {

		private final String callString;

		public SimpleCallableStatementCreator(String callString) {
			this.callString = callString;
		}

		public CallableStatement createCallableStatement(Connection con) throws SQLException {
			return con.prepareCall(this.callString);
		}

		public String getSql() {
			return callString;
		}

	}


	/**
	 * Simple adapter for PreparedStatementSetter that applies
	 * a given array of arguments.
	 */
	private static class ArgPreparedStatementSetter implements PreparedStatementSetter, ParameterDisposer {

		private final Object[] args;

		public ArgPreparedStatementSetter(Object[] args) {
			this.args = args;
		}

		public void setValues(PreparedStatement ps) throws SQLException {
			if (this.args != null) {
				for (int i = 0; i < this.args.length; i++) {
					StatementCreatorUtils.setParameterValue(ps, i + 1, SqlTypeValue.TYPE_UNKNOWN, null, this.args[i]);
				}
			}
		}

		public void cleanupParameters() {
			StatementCreatorUtils.cleanupParameters(this.args);
		}
	}


	/**
	 * Simple adapter for PreparedStatementSetter that applies
	 * given arrays of arguments and JDBC argument types.
	 */
	private static class ArgTypePreparedStatementSetter implements PreparedStatementSetter, ParameterDisposer {

		private final Object[] args;

		private final int[] argTypes;

		public ArgTypePreparedStatementSetter(Object[] args, int[] argTypes) {
			if ((args != null && argTypes == null) || (args == null && argTypes != null) ||
					(args != null && args.length != argTypes.length)) {
				throw new InvalidDataAccessApiUsageException("args and argTypes parameters must match");
			}
			this.args = args;
			this.argTypes = argTypes;
		}

		public void setValues(PreparedStatement ps) throws SQLException {
			if (this.args != null) {
				for (int i = 0; i < this.args.length; i++) {
					StatementCreatorUtils.setParameterValue(ps, i + 1, this.argTypes[i], null, this.args[i]);
				}
			}
		}

		public void cleanupParameters() {
			StatementCreatorUtils.cleanupParameters(this.args);
		}
	}


	/**
	 * Adapter to enable use of a RowCallbackHandler inside a ResultSetExtractor.
	 * <p>Uses a regular ResultSet, so we have to be careful when using it:
	 * We don't use it for navigating since this could lead to unpredictable consequences.
	 */
	private static class RowCallbackHandlerResultSetExtractor implements ResultSetExtractor {

		private final RowCallbackHandler rch;

		public RowCallbackHandlerResultSetExtractor(RowCallbackHandler rch) {
			this.rch = rch;
		}

		public Object extractData(ResultSet rs) throws SQLException {
			while (rs.next()) {
				this.rch.processRow(rs);
			}
			if (this.rch instanceof ResultReader) {
				return ((ResultReader) this.rch).getResults();
			}
			else {
				return null;
			}
		}
	}


	/**
	 * ResultSetExtractor implementation that returns an ArrayList of HashMaps.
	 */
	private static class ListResultSetExtractor implements ResultSetExtractor {

		public Object extractData(ResultSet rs) throws SQLException {
			ResultSetMetaData rsmd = rs.getMetaData();
			int numberOfColumns = rsmd.getColumnCount();
			List listOfRows = new ArrayList();
			while (rs.next()) {
				Map mapOfColValues = CollectionFactory.createLinkedMapIfPossible(numberOfColumns);
				for (int i = 1; i <= numberOfColumns; i++) {
					mapOfColValues.put(rsmd.getColumnName(i), rs.getObject(i));
				}
				listOfRows.add(mapOfColValues);
			}
			return listOfRows;
		}
	}


	/**
	 * ResultSetExtractor implementation that returns single result object.
	 */
	private static class ObjectResultSetExtractor implements ResultSetExtractor {

		private final Class requiredType;

		public ObjectResultSetExtractor(Class requiredType) {
			this.requiredType = requiredType;
		}

		public Object extractData(ResultSet rs) throws SQLException {
			ResultSetMetaData rsmd = rs.getMetaData();
			int nrOfColumns = rsmd.getColumnCount();
			if (nrOfColumns != 1) {
				throw new IncorrectResultSizeDataAccessException(
						"Expected single column but found " + nrOfColumns, 1, nrOfColumns);
			}
			if (!rs.next()) {
				throw new IncorrectResultSizeDataAccessException("Expected single row but found none", 1, 0);
			}
			Object result = rs.getObject(1);
			if (rs.next()) {
				throw new IncorrectResultSizeDataAccessException("Expected single row but found more than one", 1, -1);
			}
			if (result != null && this.requiredType != null && !this.requiredType.isInstance(result)) {
				if (String.class == this.requiredType) {
					result = result.toString();
				} 
				else if (Number.class.isAssignableFrom(this.requiredType) && Number.class.isInstance(result)) {
					try {
						if (Byte.class.isAssignableFrom(this.requiredType)) {
							result = new Byte(((Number) result).byteValue());
						}
						else if (Short.class.isAssignableFrom(this.requiredType)) {
							result = new Short(((Number) result).shortValue());
						}
						else if (Integer.class.isAssignableFrom(this.requiredType)) {
							result = new Integer(((Number) result).intValue());
						}
						else if (Long.class.isAssignableFrom(this.requiredType)) {
							result = new Long(((Number) result).longValue());
						}
						else if (Float.class.isAssignableFrom(this.requiredType)) {
							result = new Float(((Number) result).floatValue());
						}
						else if (Double.class.isAssignableFrom(this.requiredType)) {
							result = new Double(((Number) result).doubleValue());
						}
						else if (BigDecimal.class.isAssignableFrom(this.requiredType)) {
							result = new BigDecimal(((Number) result).doubleValue());
						}
						else if (BigInteger.class.isAssignableFrom(this.requiredType)) {
							result = new BigInteger(result.toString());
						}
						else {
							throw new NumberFormatException(
									"Could not convert [" + result + "] to required type [" + this.requiredType.getName() + "]");
						}
					}
					catch (NumberFormatException ne) {
						throw new TypeMismatchDataAccessException(
								"Result object (db-type=\"" + rsmd.getColumnTypeName(1)
										+ "\" value=\"" + result + "\") is of type ["
										+ rsmd.getColumnClassName(1)
										+ "] and could not be converted to required type ["
										+ this.requiredType.getName() + "]");
					}
				}
				else {
					throw new TypeMismatchDataAccessException(
							"Result object (db-type=\"" + rsmd.getColumnTypeName(1)
									+ "\" value=\"" + result + "\") is of type ["
									+ rsmd.getColumnClassName(1)
									+ "] and not of required type ["
									+ this.requiredType.getName() + "]");
				}
			}
			return result;
		}
	}

}