com.zh.oukele.util;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
public class CreateSqlUtil {
public static void main(String[] args) {
Map<String ,Object> map =
new HashMap<>
();
map.put("stuName","欧可乐"
);
map.put("stuAge",20
);
map.put("stuSex","男"
);
map.put("Key_stuId","ASDF"
);
map.put("Key_stuSex","ASDF"
);
try {
System.out.println(getSql("table_name", "delete", map,
false, ""
));
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* 动态组装 简单sql语法
* @param tableName 表名
* @param operation 操作标识符 select|delete|update ,默认为 select
* @param mapData 数据的map集合
* @param useMySQL true|false , false 为使用动态组装SQL，true为使用自已的sql
* @param mySql 自已的sql
* 注意：update 这里，where xxx = xxx ,的时候，mapData 里的键必须要有 Key_ 前缀（其他的 并不影响到）
*
* @return
* @throws Exception
*/
public static String getSql(String tableName, String operation, Map<?,?> mapData,
boolean useMySQL,String mySql)
throws Exception {
String sql =
null;
// 使用组装sql的功能
if( !
useMySQL){
if( !(tableName !=
null && !tableName.equals("") && tableName.length() > 0
) ){
throw new Exception(" 参数 tableName 的值为空！"
);
}else if( !(mapData !=
null && !mapData.equals("") && mapData.size() > 0
) ){
throw new Exception(" 参数 mapData 的值为空！"
);
}
// 操作标识 默认为 select
String operations = "select"
;
String condition = " a.* from " + tableName + " a where "
;
if( operation !=
null && !operation.equals(""
) ){
if( operation.equals("update") || operation.equals("UPDATE"
) ){
operations = "update"
;
condition = " " + tableName + " a set "
;
}else if( operation.equals("delete") || operation.equals("DELETE"
) ){
operations = "delete"
;
condition = " from " + tableName + " a where "
;
}else if( operation.equals("insert") || operation.equals("INSERT"
) ){
operations = "insert"
;
condition = " into " + tableName + " values ("
;
String link = ""
;
Iterator<?> iterator =
mapData.keySet().iterator();
while (iterator.hasNext()) {
String next =
(String) iterator.next();
condition += link +
next;
link = ","
;
}
condition += ") values( "
;
}
}
String value= ""
;
String link =""
;
String keyValueOperations = " where "
;
Iterator<?
extends Map.Entry<?, ?>> iterator =
mapData.entrySet().iterator();
while (iterator.hasNext()) {
Map.Entry<?, ?> next =
iterator.next();
if( next.getValue()
instanceof String ){
value = "‘" + next.getValue() +"‘"
;
}else {
value = "" + next.getValue() +""
;
}
if( next.getKey().toString().lastIndexOf("Key_") == -1
){
if( !operations.equals("insert"
)){
if( operations.equals("select") || operations.equals("delete"
)){
condition += link + "a." +
next.getKey();
condition += "=" +
value;
link = " and "
;
}else {
condition += link + "a." +
next.getKey();
condition += "=" +
value;
link = ","
;
}
}else {
condition += link +
value;
link = ","
;
}
}else {
continue;
}
}
// 组装 insert sql 的结尾
if( operations.equals("insert"
) ){
condition += ")"
;
}else if(operations.equals("update")){
// 组装 update sql 的结尾
condition += " where "
;
String and = ""
;
Iterator<?
extends Map.Entry<?, ?>> iterator1 =
mapData.entrySet().iterator();
while (iterator1.hasNext()) {
Map.Entry<?, ?> next =
iterator1.next();
if( next.getValue()
instanceof String ){
value = "‘" + next.getValue() +"‘"
;
}else {
value = "" + next.getValue() +""
;
}
String key =
next.getKey().toString();
if( key.lastIndexOf("Key_") != -1
){
key = key.substring(key.indexOf("Key_")+ 4
,key.length());
condition += and +"a." +key + "=" +
value;
and = " and "
;
}
}
}
sql = operations +
condition;
}else {
// 不使用组装sql的功能
sql =
mySql;
}
return sql;
}
}
Java 实现简单的SQL动态组装工具类
标签：equals ble boolean import int @param exception throw key
