⑴ java過濾非法字元的filter
filter代碼在pujia12345提供的代碼上改的；
jsp頁面的編碼你設成你自己的，我用的是-8。
input.jsp輸入後，正常跳轉到handle.jsp，而禁詞已經被過濾。
filter：
package test;
import java.io.*;
import javax.servlet.*;
import java.util.*;
public class MyFilter implements Filter
{
private List<String> unString;
public void init(FilterConfig filterConfig) throws ServletException
{
unString = new ArrayList<String>();
unString.add("日");
}
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
throws IOException, ServletException
{
String content = request.getParameter("content");//需要過濾的參數
if(content!=null){
for (int i = 0; i < unString.size(); i++)
{
String strIllegal = unString.get(i);
if (content.indexOf(strIllegal) >= 0)
{
content = content.replaceAll(strIllegal, "");//非法字元替換成空
}
request.setAttribute("content", content);//為request設置屬性保存修改後的值
}
}
chain.doFilter(request, response);
}
public void destroy()
{
//System.out.println("過濾器銷毀");
}
}
//---------------------------//
web.xml:
<filter>
<filter-name>myfilter</filter-name>
<filter-class>test.MyFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>myfilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
//---------------------------//
輸入頁面input.jsp:
<%@page contentType="text/html;charset=utf-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>input.jsp</title>
</head>
<body>
<form action="handle.jsp" method="post">
<input type="text" name="content" />
<input type="submit" value=" 提交 " />
</form>
</body>
</html>
//---------------------------//
input提交的頁面handle.jsp:
<%@page contentType="text/html;charset=utf-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title> handle.jsp </title>
</head>
<body>
<%
String content = (String)request.getAttribute("content");
out.println(content);
%>
</body>
</html>
⑵ 防sql注入到底應過濾哪些字元
一般來說，這樣處理即可：
所有參數都當作字元串處理，用單引號括起來。另外就是要把字元串中的單引號替換掉。
⑶ 求過濾SQL非法字元的函數
Function CheckSql() '防止SQL注入
Dim sql_injdata
SQL_injdata = "'||exec|insert|select|delete|update|count|*|%|chr|mid|master|truncate|char|declare"
SQL_inj = split(SQL_Injdata,"|")
If Request.QueryString<>"" Then
For Each SQL_Get In Request.QueryString
For SQL_Data=0 To Ubound(SQL_inj)
if instr(Request.QueryString(SQL_Get),Sql_Inj(Sql_DATA))>0 Then
Response.Write "<Script Language='javascript'>{alert('請不要在參數中包含非法字元！');history.back(-1)}</Script>"
Response.end
end if
next
Next
End If
If Request.Form<>"" Then
For Each Sql_Post In Request.Form
For SQL_Data=0 To Ubound(SQL_inj)
if instr(Request.Form(Sql_Post),Sql_Inj(Sql_DATA))>0 Then
Response.Write "<Script Language='javascript'>{alert('請不要在參數中包含非法字元！');history.back(-1)} </Script>"
Response.end
end if
next
next
end if
End Function
⑷ JAVA中如何過濾字元串裡面特殊字元
class test
{
public static void main(String []args)
{
String a = "1111-22-33 13:15:46",b=new String();
int i,j,t;
for(i=0;i<a.length();i++)
if(a.charAt(i)!='-' && a.charAt(i)!=':' && a.charAt(i)!=' ')
b=b+a.charAt(i);
System.out.println(b);
}
}
⑸ java 字元串過濾
packagetest;
importjava.util.HashMap;
/**
*maxLength-需要過濾最長字元串的長度
*filterStrs<string,string>-需要過濾字元串的集合，key為需要過濾字元串，value為過濾成的字元串如"*"
*@authorAdministrator
*
*/
publicclassTest{
privateintmaxLength;
privateHashMap<String,String>filterStrs=newHashMap<String,String>();
/**
*初始化需要過濾掉*的數量
*/
privateStringinitStr(intn){
StringBuffersb=newStringBuffer();
for(inti=0;i<n;i++){
sb.append('*');
}
returnsb.toString();
}
/**
*str-被過濾得字元串
*s-需要過濾得字元串
*獲得剩下未過濾的字元串
*/
privateStringgetNextStr(Stringstr,intstart,intslength){
if(start==0){
str=str.substring(slength);
}elseif(start+slength<str.length()){
str=str.substring(start+slength);
}
returnstr;
}
/**
*str-被過濾得字元串
*s-需要過濾得字元串
*獲得過濾後的字元串
*/
(StringBuffersb,Stringstr,intstart,Strings){
if(start!=0){
sb.append(str.substring(0,start));
}
sb.append(filterStrs.get(s));
returnsb;
}
/**
*str-被過濾的字元串
*過濾，並組合過濾後的字元串
*/
publicStringfilter(Stringstr){
StringBufferresultStr=newStringBuffer();
for(intstart=0;start<str.length();start++){
for(intend=start+1;end<=str.length()&&end<=start+maxLength;end++){
Strings=str.substring(start,end);
intslength=s.length();
if(filterStrs.containsKey(s)){
resultStr=getFilterStr(resultStr,str,start,s);
str=getNextStr(str,start,slength);
start=0;
end=start;
}
}
}
resultStr.append(str);
returnresultStr.toString();
}
publicvoidput(Stringkey){
intkeyLength=key.length();
filterStrs.put(key,initStr(keyLength));
if(keyLength>this.maxLength)
maxLength=keyLength;
}
publicstaticvoidmain(String[]agrs){
Testt=newTest();
t.put("TMD");
t.put("TNND");
t.put("NND");
System.out.println(t.filter("TMD，TNND..TMDTMDTMDTMD.tTNNDTMDTNNDTNNDTNND"));
}
}
⑹ JAVA特殊字元過濾方法
public static String StringFilter(String str) throws PatternSyntaxException {
// 只允許字母和數字
// String regEx = "[^a-zA-Z0-9]";
// 清除掉所有特殊字元
String regEx="[`~!@#$%^&*()+=|{}':;',\\[\\].<>/?~！@#￥%……&*（）——+|{}【】『；：」「』。，、？]";
Pattern p = Pattern.compile(regEx);
Matcher m = p.matcher(str);
return m.replaceAll("").trim();
}