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/* * Copyright 2009-2010 the original author or authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License i distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.wantscart.jade.provider.jdbc; import org.apache.commons.lang.ClassUtils; import org.springframework.dao.DataAccessException; import org.springframework.jdbc.core.PreparedStatementCallback; import org.springframework.jdbc.core.PreparedStatementSetter; import org.springframework.jdbc.core.SingleColumnRowMapper; import org.springframework.jdbc.support.JdbcUtils; import java.lang.reflect.Array; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; /** * ? {@link PreparedStatementCallback} * * @author [qieqie.wang@gmail.com] * @author [in355hz@gmail.com] */ public class PreparedStatementCallbackReturnId implements PreparedStatementCallback { private final PreparedStatementSetter setter; private final Class<?> returnType; private final Class<?> idType; private final Class<?> wrappedIdType; private final SingleColumnRowMapper mapper; public PreparedStatementCallbackReturnId(PreparedStatementSetter setter, Class<?> returnType) { this.setter = setter; if (returnType.isPrimitive()) { returnType = ClassUtils.primitiveToWrapper(returnType); } this.returnType = returnType; Class<?> idType = returnType; if (returnType.isArray()) { idType = returnType.getComponentType(); } this.idType = idType; if (idType.isPrimitive()) { idType = ClassUtils.primitiveToWrapper(idType); } this.wrappedIdType = idType; this.mapper = new SingleColumnRowMapper(idType); if (wrappedIdType != Integer.class && wrappedIdType != Long.class && wrappedIdType != Number.class) { throw new IllegalArgumentException( "wrong return type(int/long type or its array type only): " + returnType); } } @Override public Object doInPreparedStatement(PreparedStatement ps) throws SQLException, DataAccessException { if (setter != null) { setter.setValues(ps); } int updated = ps.executeUpdate(); if (updated == 0) { if (returnType.isArray()) { return Array.newInstance(wrappedIdType, 0); } else { return defaultValueOf(wrappedIdType); } } ResultSet keys = ps.getGeneratedKeys(); if (keys != null) { try { Object ret = null; if (returnType.isArray()) { keys.last(); int length = keys.getRow(); keys.beforeFirst(); ret = Array.newInstance(wrappedIdType, length); } for (int i = 0; keys.next(); i++) { Object value = mapper.mapRow(keys, i); if (value == null && idType.isPrimitive()) { // ?primitive??null?? value = defaultValueOf(wrappedIdType); } if (ret != null) { Array.set(ret, i + 1, value); } else { ret = value; break; } } return ret; } finally { JdbcUtils.closeResultSet(keys); } } else { if (returnType.isArray()) { return Array.newInstance(wrappedIdType, 0); } else { return defaultValueOf(wrappedIdType); } } } private static Object defaultValueOf(Class<?> numberType) { if (numberType == Integer.class) { return new Integer(-1); } else if (numberType == Long.class) { return new Long(-1); } throw new Error("wrong number type: " + numberType); } }