Filter special characters in Java to prevent SQL injection

 PackageCn.com.hbivt.util;  Public classStringUtils {//filter the characters submitted through the page form       Private StaticString[][] filterchars={{"<", "&lt;"},{">", "&gt;"},{"", "&nbsp;"},{"\" "," &quot; "},{" & ", "&amp;"},                                          {"/", "& #47;"},{"\", "& #92;"},{"\ n", "<br>"}}; //filter the characters processed and submitted through JavaScript scripts       Private Staticstring[][] filterscriptchars={{"\ n", "\ ' +\ ' \\n\ ' +\ '"},                                                              {"\ r", "},{" \ "," \ ' +\ ' \\\\\ ' +\ ' "},                                                                      {"\ '", "\ ' +\ ' \\\ ' \ ' +\ '"}}; /*** Connect strings with special characters *@paramstrings array of strings to concatenate *@paramspilit_sign Connection Characters *@returnConnection String*/          Public Staticstring Stringconnect (string[] strings,string spilit_sign) {string str="";  for(inti=0;i<strings.length;i++) {str+=strings[i]+spilit_sign; }            returnstr; }            /*** Filter the special characters in the string *@paramStr to filter the string *@returnFiltered String*/          Public Staticstring Stringfilter (String str) {string[] Str_arr=stringspilit (str, "");  for(inti=0;i<str_arr.length;i++){               for(intj=0;j<filterchars.length;j++){                if(filterchars[j][0].equals (Str_arr[i]) str_arr[i]=filterchars[j][1]; }            }            return(Stringconnect (Str_arr, "") . Trim (); }            /*** Filter special characters in the script (including carriage return (\ n) and line break (\ r)) *@paramStr to filter the string *@returnFiltered String * 2004-12-21 yan*/   Public Staticstring Stringfilterscriptchar (String str) {string[] Str_arr=stringspilit (str, "");  for(inti=0;i<str_arr.length;i++){       for(intj = 0; J < Filterscriptchars.length; J + +) {        if(filterscriptchars[j][0].equals (Str_arr[i]) str_arr[i]= Filterscriptchars[j][1]; }   }   return(Stringconnect (Str_arr, "") . Trim (); }              /*** Split String *@paramstr to split the string *@paramspilit_sign the split flag of a String *@returnthe resulting string array after splitting*/          Public Staticstring[] Stringspilit (String str,string spilit_sign) {string[] spilit_string=Str.split (spilit_sign); if(Spilit_string[0].equals ("") ) {string[] new_string=NewString[spilit_string.length-1];  for(inti=1;i<spilit_string.length;i++) New_string[i-1]=Spilit_string[i]; returnnew_string; }            Else             returnspilit_string; }            /*** String Character set conversion *@paramstr to convert the string *@returnconverted string*/          Public Staticstring Stringtranscharset (String str) {string New_str=NULL; Try{new_str=NewString (Str.getbytes ("iso-8859-1"), "GBK"); }            Catch(Exception e) {e.printstacktrace (); }            returnNew_str; }            /*** Test String processing class *@paramargs Console input parameters*/          Public Static voidMain (string[] args) {//test String FilteringString t_str1= "; System.out.println ("Before filtering:" +t_str1); System.out.println ("After filtering:" +Stringutils.stringfilter (T_STR1)); //Test Merge StringString[] t_str_arr1={"pg_1", "pg_2", "Pg_3"}; String T_STR2=stringutils.stringconnect (T_STR_ARR1, ",");            System.out.println (T_STR2); //Test Split stringString[] T_str_arr2=stringutils.stringspilit (T_STR2, ",");  for(inti=0;i<t_str_arr2.length;i++) {System.out.println (t_str_arr2[i]); }          }   }

Filter special characters in Java to prevent SQL injection