org.dromara.hutool.db.sql.NamedSql Maven / Gradle / Ivy
/*
* Copyright (c) 2013-2024 Hutool Team and hutool.cn
*
* 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 is 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 org.dromara.hutool.db.sql;
import org.dromara.hutool.core.array.ArrayUtil;
import org.dromara.hutool.core.map.MapUtil;
import org.dromara.hutool.core.text.StrUtil;
import java.util.Collection;
import java.util.Map;
/**
* 使用命名占位符的SQL，例如：select * from table where field1=:name1
* 支持的占位符格式为：
*
* 1、:name
* 2、@name
* 3、?name
*
*
* @author looly
* @since 4.0.10
*/
public class NamedSql extends BoundSql {
private static final char[] NAME_START_CHARS = {':', '@', '?'};
private final String namedSql;
private final Map paramMap;
/**
* 构造
*
* @param namedSql 命名占位符的SQL
* @param paramMap 名和参数的对应Map
*/
public NamedSql(final String namedSql, final Map paramMap) {
this.namedSql = namedSql;
this.paramMap = paramMap;
parse(namedSql, paramMap);
}
/**
* 获取原始地带名称占位符的SQL语句
*
* @return 名称占位符的SQL
*/
public String getNamedSql() {
return namedSql;
}
/**
* 获取原始参数名和参数值对应关系参数表
*
* @return 参数名和参数值对应关系参数表
*/
public Map getParamMap() {
return paramMap;
}
/**
* 解析命名占位符的SQL
*
* @param namedSql 命名占位符的SQL
* @param paramMap 名和参数的对应Map
*/
private void parse(final String namedSql, final Map paramMap) {
if (MapUtil.isEmpty(paramMap)) {
setSql(namedSql);
return;
}
final int len = namedSql.length();
final StringBuilder name = new StringBuilder();
final StringBuilder sqlBuilder = new StringBuilder();
char c;
Character nameStartChar = null;
for (int i = 0; i < len; i++) {
c = namedSql.charAt(i);
if (ArrayUtil.contains(NAME_START_CHARS, c)) {
// 新的变量开始符出现，要处理之前的变量
replaceVar(nameStartChar, name, sqlBuilder, paramMap);
nameStartChar = c;
} else if (null != nameStartChar) {
// 变量状态
if (isGenerateChar(c)) {
// 变量名
name.append(c);
} else {
// 非标准字符也非变量开始的字符出现表示变量名结束，开始替换
replaceVar(nameStartChar, name, sqlBuilder, paramMap);
nameStartChar = null;
sqlBuilder.append(c);
}
} else {
// 变量以外的字符原样输出
sqlBuilder.append(c);
}
}
// 收尾，如果SQL末尾存在变量，处理之
if (name.length() > 0) {
replaceVar(nameStartChar, name, sqlBuilder, paramMap);
}
setSql(sqlBuilder.toString());
}
/**
* 替换变量，如果无变量，原样输出到SQL中去
*
* @param nameStartChar 变量开始字符
* @param name 变量名
* @param sqlBuilder 结果SQL缓存
* @param paramMap 变量map（非空）
*/
private void replaceVar(final Character nameStartChar, final StringBuilder name, final StringBuilder sqlBuilder, final Map paramMap) {
if (name.length() == 0) {
if (null != nameStartChar) {
// 类似于:的情况，需要补上:
sqlBuilder.append(nameStartChar);
}
// 无变量，按照普通字符处理
return;
}
// 变量结束
final String nameStr = name.toString();
if (paramMap.containsKey(nameStr)) {
// 有变量对应值（值可以为null），替换占位符为?，变量值放入相应index位置
Object paramValue = paramMap.get(nameStr);
if ((paramValue instanceof Collection || ArrayUtil.isArray(paramValue)) && StrUtil.containsIgnoreCase(sqlBuilder, "in")) {
if (paramValue instanceof Collection) {
// 转为数组
paramValue = ((Collection) paramValue).toArray();
}
// 可能为select in (xxx)语句，则拆分参数为多个参数，变成in (?,?,?)
final int length = ArrayUtil.length(paramValue);
for (int i = 0; i < length; i++) {
if (0 != i) {
sqlBuilder.append(',');
}
sqlBuilder.append('?');
addParam(ArrayUtil.get(paramValue, i));
}
} else {
sqlBuilder.append('?');
addParam(paramValue);
}
} else {
// 无变量对应值，原样输出
sqlBuilder.append(nameStartChar).append(name);
}
//清空变量，表示此变量处理结束
name.setLength(0);
}
/**
* 是否为标准的字符，包括大小写字母、下划线和数字
*
* @param c 字符
* @return 是否标准字符
*/
private static boolean isGenerateChar(final char c) {
return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || c == '_' || (c >= '0' && c <= '9');
}
}