1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one or more 3 * contributor license agreements. See the NOTICE file distributed with 4 * this work for additional information regarding copyright ownership. 5 * The ASF licenses this file to You under the Apache License, Version 2.0 6 * (the "License"); you may not use this file except in compliance with 7 * the License. You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 */ 17 package org.apache.commons.dbutils.handlers; 18 19 import java.sql.ResultSet; 20 import java.sql.SQLException; 21 22 import org.apache.commons.dbutils.ResultSetHandler; 23 import org.apache.commons.dbutils.RowProcessor; 24 25 /** 26 * {@code ResultSetHandler} implementation that converts the first 27 * {@code ResultSet} row into a JavaBean. This class is thread safe. 28 * 29 * @param <T> the target bean type 30 * @see org.apache.commons.dbutils.ResultSetHandler 31 */ 32 public class BeanHandler<T> implements ResultSetHandler<T> { 33 34 /** 35 * The Class of beans produced by this handler. 36 */ 37 private final Class<? extends T> type; 38 39 /** 40 * The RowProcessor implementation to use when converting rows 41 * into beans. 42 */ 43 private final RowProcessor convert; 44 45 /** 46 * Creates a new instance of BeanHandler. 47 * 48 * @param type The Class that objects returned from {@code handle()} 49 * are created from. 50 */ 51 public BeanHandler(final Class<? extends T> type) { 52 this(type, ArrayHandler.ROW_PROCESSOR); 53 } 54 55 /** 56 * Creates a new instance of BeanHandler. 57 * 58 * @param type The Class that objects returned from {@code handle()} 59 * are created from. 60 * @param convert The {@code RowProcessor} implementation 61 * to use when converting rows into beans. 62 */ 63 public BeanHandler(final Class<? extends T> type, final RowProcessor convert) { 64 this.type = type; 65 this.convert = convert; 66 } 67 68 /** 69 * Convert the first row of the {@code ResultSet} into a bean with the 70 * {@code Class} given in the constructor. 71 * @param resultSet {@code ResultSet} to process. 72 * @return An initialized JavaBean or {@code null} if there were no 73 * rows in the {@code ResultSet}. 74 * 75 * @throws SQLException if a database access error occurs 76 * @see org.apache.commons.dbutils.ResultSetHandler#handle(java.sql.ResultSet) 77 */ 78 @Override 79 public T handle(final ResultSet resultSet) throws SQLException { 80 return resultSet.next() ? this.convert.toBean(resultSet, this.type) : null; 81 } 82 83 }