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本项目主要弥补在使用mybatis3+springmvc+jquery easyui快速搭建web应用系统是遇到的框架不足.
主要工作包括：
1，扩展了ApplicationContextAware，通过单例注入spring容器，提供spring容器外的bean获取方法
2，扩展了apache shiro框架，统一了安全结构
3，扩展了mybatis3拦截器，在两个拦截器中自动完成分页注入，实现内存分页。
4，分页设计数据库方言
5，提供了一个easyuigrid的模型
6，提供了java泛型的jstl
7， xml工具包等一些小工具
package net.sourceforge.orm.dialect;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
* @author [email protected]
**/
public class MSPageHepler {
/**
* 得到查询总数的sql
*/
public static String getCountString(String querySelect) {
querySelect = getLineSql(querySelect);
int orderIndex = getLastOrderInsertPoint(querySelect);
int formIndex = getAfterFormInsertPoint(querySelect);
String select = querySelect.substring(0, formIndex);
// 如果SELECT 中包含 DISTINCT 只能在外层包含COUNT
if (select.toLowerCase().indexOf("select distinct") != -1 || querySelect.toLowerCase().indexOf("group by") != -1) {
return new StringBuffer(querySelect.length()).append("select count(1) count from (").append(querySelect.substring(0, orderIndex)).append(" ) t").toString();
} else {
return new StringBuffer(querySelect.length()).append("select count(1) count ").append(querySelect.substring(formIndex, orderIndex)).toString();
}
}
/**
* 得到最后一个Order By的插入点位置
*
* @return 返回最后一个Order By插入点的位置
*/
private static int getLastOrderInsertPoint(String querySelect) {
int orderIndex = querySelect.toLowerCase().lastIndexOf("order by");
if (orderIndex == -1) {
orderIndex = querySelect.length();
}
if (!isBracketCanPartnership(querySelect.substring(orderIndex, querySelect.length()))) {
throw new RuntimeException("My SQL 分页必须要有Order by 语句!");
}
return orderIndex;
}
/**
* 得到分页的SQL
*
* @param offset
* 偏移量
* @param limit
* 位置
* @return 分页SQL
*/
public static String getLimitString(String querySelect, int offset, int limit) {
querySelect = getLineSql(querySelect);
int selectIndex = querySelect.toUpperCase().lastIndexOf("SELECT");
if (selectIndex > -1) {
querySelect = querySelect.substring(0, selectIndex) + "SELECT TOP " + (limit + offset) + querySelect.substring(selectIndex + 6);
}
String sql = "SELECT * FROM(SELECT ROW_NUMBER () OVER (ORDER BY getdate()) rownum,* FROM( " + querySelect + " ) A ) B WHERE B.rownum > " + offset + " AND B.rownum <= "
+ (limit + offset);
return sql;
}
/**
* 将SQL语句变成一条语句，并且每个单词的间隔都是1个空格
*
* @param sql
* SQL语句
* @return 如果sql是NULL返回空，否则返回转化后的SQL
*/
private static String getLineSql(String sql) {
return sql.replaceAll("[\r\n]", " ").replaceAll("\\s{2,}", " ");
}
/**
* 得到SQL第一个正确的FROM的的插入点
*/
private static int getAfterFormInsertPoint(String querySelect) {
String regex = "\\s+FROM\\s+";
Pattern pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE);
Matcher matcher = pattern.matcher(querySelect);
while (matcher.find()) {
int fromStartIndex = matcher.start(0);
String text = querySelect.substring(0, fromStartIndex);
if (isBracketCanPartnership(text)) {
return fromStartIndex;
}
}
return 0;
}
/**
* 判断括号"()"是否匹配,并不会判断排列顺序是否正确
*
* @param text
* 要判断的文本
* @return 如果匹配返回TRUE,否则返回FALSE
*/
private static boolean isBracketCanPartnership(String text) {
if (text == null || (getIndexOfCount(text, '(') != getIndexOfCount(text, ')'))) {
return false;
}
return true;
}
/**
* 得到一个字符在另一个字符串中出现的次数
*
* @param text
* 文本
* @param ch
* 字符
*/
private static int getIndexOfCount(String text, char ch) {
int count = 0;
for (int i = 0; i < text.length(); i++) {
count = (text.charAt(i) == ch) ? count + 1 : count;
}
return count;
}
}