java配置多個過濾器優先級以及幾個常用過濾器操作
一個項目中不出意外的話會有兩個以上的過濾器，但是直接不配置的話他會按照你的過濾器名字排序執行，這樣的話可能會導致一些性能上或者邏輯上的問題。那麼，控制一下執行順序是我們所必須要做的。
java封裝瞭一個FilterRegistrationBean對象，可以把他比作一個容器，將過濾器套入這個對象中，可以對這個對象進行優先級設置、過濾規則設置等屬性，下面是幾個常用的過濾器以及過濾器配置。
過濾器配置：
package cn.ask.filter;
import javax.servlet.DispatcherType;
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.filter.DelegatingFilterProxy;
/**
* Title: FilterConfig
* @date 2018年10月25日
* @version V1.0
* Description: 過濾器配置
*/
@SuppressWarnings("all")
@Configuration
public class FilterConfig {
/**
* @Description 防xss攻擊過濾器
* @date 2018年8月16日下午4:55:44
*/
@Bean
public FilterRegistrationBean xssFilterRegistration() {
FilterRegistrationBean registration = new FilterRegistrationBean();
registration.setDispatcherTypes(DispatcherType.REQUEST);
registration.setFilter(new XssFilter());
registration.addUrlPatterns("/*");
registration.setName("xssFilter");
//order數字越小越先執行
registration.setOrder(1);
return registration;
}
/**
* @Description 獲取登錄信息
* @date 2018年10月25日上午9:14:48
*/
@Bean
public FilterRegistrationBean cookieRegistration() {
FilterRegistrationBean registration = new FilterRegistrationBean();
registration.setDispatcherTypes(DispatcherType.REQUEST);
registration.setFilter(new CookieFilter());
registration.addUrlPatterns("/*");
registration.setName("firstFilter");
registration.setOrder(2);
return registration;
}
}
常用過濾器之一：
sso單點登錄（使用cookie記錄跨站數據）
package cn.ask.filter;
import java.io.IOException;
import java.net.URLDecoder;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import org.apache.commons.lang3.StringUtils;
/**
* Servlet Filter implementation class FirstFilter
*/
public class CookieFilter implements Filter {
/**
* Default constructor.
*/
public CookieFilter() {
// TODO Auto-generated constructor stub
}
/**
* @see Filter#destroy()
*/
public void destroy() {
// TODO Auto-generated method stub
}
/**
* @see Filter#doFilter(ServletRequest, ServletResponse, FilterChain)
*/
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
HttpServletRequest req = (HttpServletRequest) request;
String tokenHeader = req.getHeader("token");
if(StringUtils.isBlank(tokenHeader)) {
Cookie[] cookies = req.getCookies();
if (cookies != null && cookies.length > 0) {
for (int i = 0; i < cookies.length; i++) {
String name = cookies[i].getName();
String value = cookies[i].getValue();
if ("user_accesstoken".equals(name)) { // 用戶token
req.setAttribute("token", URLDecoder.decode(value, "utf-8"));
}
if ("user_avatar".equals(name)) { // 頭像
req.setAttribute("avatar", URLDecoder.decode(value, "utf-8"));
}
if ("user_nickname".equals(name)) { // 昵稱
req.setAttribute("nickname", URLDecoder.decode(value, "utf-8"));
}
String token = (String) req.getAttribute("token");
if (StringUtils.isBlank(token)) {
req.setAttribute("isLogin", "no");
} else {
req.setAttribute("isLogin", "yes");
}
}
}else {
req.removeAttribute("token");
req.removeAttribute("avatar");
req.removeAttribute("nickname");
req.setAttribute("isLogin", "no");
}
} else {
req.setAttribute("token", tokenHeader);
}
chain.doFilter(request, response);
}
/**
* @see Filter#init(FilterConfig)
*/
public void init(FilterConfig fConfig) throws ServletException {
// TODO Auto-generated method stub
}
}
常用過濾器之二：
xss過濾以及防html註入過濾（包括過濾敏感詞）
package cn.ask.filter;
import java.io.IOException;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
/**
* Title: XssFilter
* @date 2018年8月16日
* @version V1.0
* Description: xss過濾
*/
public class XssFilter implements Filter {
@Override
public void init(FilterConfig config) throws ServletException {
}
@Override
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
throws IOException, ServletException {
XssHttpServletRequestWrapper xssRequest = new XssHttpServletRequestWrapper((HttpServletRequest) request);
chain.doFilter(xssRequest, response);
}
@Override
public void destroy() {
}
}
package cn.ask.filter;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.util.LinkedHashMap;
import java.util.Map;
import javax.servlet.ReadListener;
import javax.servlet.ServletInputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import org.apache.commons.io.IOUtils;
import org.apache.commons.lang3.StringUtils;
import org.springframework.http.HttpHeaders;
import org.springframework.http.MediaType;
/**
* Title: XssHttpServletRequestWrapper
* @date 2018年8月16日
* @version V1.0
* Description: XSS過濾處理
*/
public class XssHttpServletRequestWrapper extends HttpServletRequestWrapper {
/**沒被包裝過的HttpServletRequest（特殊場景，需要自己過濾*/
HttpServletRequest orgRequest;
/**html過濾*/
private final static HtmlFilter HTMLFILTER = new HtmlFilter();
public XssHttpServletRequestWrapper(HttpServletRequest request) {
super(request);
orgRequest = request;
}
@Override
public ServletInputStream getInputStream() throws IOException {
//非json類型，直接返回
if(!super.getHeader(HttpHeaders.CONTENT_TYPE).equalsIgnoreCase(MediaType.APPLICATION_JSON_VALUE)){
return super.getInputStream();
}
//為空，直接返回
String json = IOUtils.toString(super.getInputStream(), "utf-8");
if (StringUtils.isBlank(json)) {
return super.getInputStream();
}
//xss過濾
json = xssEncode(json);
final ByteArrayInputStream bis = new ByteArrayInputStream(json.getBytes());
return new ServletInputStream() {
@Override
public boolean isFinished() {
return true;
}
@Override
public boolean isReady() {
return true;
}
@Override
public void setReadListener(ReadListener readListener) {
}
@Override
public int read() throws IOException {
return bis.read();
}
};
}
@Override
public String getParameter(String name) {
String value = super.getParameter(xssEncode(name));
if (StringUtils.isNotBlank(value)) {
value = xssEncode(value);
}
return value;
}
@Override
public String[] getParameterValues(String name) {
String[] parameters = super.getParameterValues(name);
if (parameters == null || parameters.length == 0) {
return null;
}
for (int i = 0; i < parameters.length; i++) {
parameters[i] = xssEncode(parameters[i]);
}
return parameters;
}
@Override
public Map<String,String[]> getParameterMap() {
Map<String,String[]> map = new LinkedHashMap<>();
Map<String,String[]> parameters = super.getParameterMap();
for (String key : parameters.keySet()) {
String[] values = parameters.get(key);
for (int i = 0; i < values.length; i++) {
values[i] = xssEncode(values[i]);
}
map.put(key, values);
}
return map;
}
@Override
public String getHeader(String name) {
String value = super.getHeader(xssEncode(name));
if (StringUtils.isNotBlank(value)) {
value = xssEncode(value);
}
return value;
}
//富文本內容放行
private String xssEncode(String input) {
if(!input.startsWith("<p")&&!input.startsWith("<ol")&&!input.startsWith("<ul")&&!input.startsWith("<hr/>")) {
input=HTMLFILTER.filter(input);
}
//敏感詞過濾
input=SensitiveWordUtils.getSensitiveWordUtils().replaceSensitiveWord(input, '*', 2);
return input;
}
/**
* 獲取最原始的request
*/
public HttpServletRequest getOrgRequest() {
return orgRequest;
}
/**
* 獲取最原始的request
*/
public static HttpServletRequest getOrgRequest(HttpServletRequest request) {
if (request instanceof XssHttpServletRequestWrapper) {
return ((XssHttpServletRequestWrapper) request).getOrgRequest();
}
return request;
}
}
package cn.ask.filter;
import java.util.*;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
import java.util.logging.Logger;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
* Title: HTMLFilter
* @date 2018年8月16日
* @version V1.0
* Description: 防html註入
*/
public final class HtmlFilter {
/** regex flag union representing /si modifiers in php **/
private static final int REGEX_FLAGS_SI = Pattern.CASE_INSENSITIVE | Pattern.DOTALL;
private static final Pattern P_COMMENTS = Pattern.compile("<!--(.*?)-->", Pattern.DOTALL);
private static final Pattern P_COMMENT = Pattern.compile("^!--(.*)--$", REGEX_FLAGS_SI);
private static final Pattern P_TAGS = Pattern.compile("<(.*?)>", Pattern.DOTALL);
private static final Pattern P_END_TAG = Pattern.compile("^/([a-z0-9]+)", REGEX_FLAGS_SI);
private static final Pattern P_START_TAG = Pattern.compile("^([a-z0-9]+)(.*?)(/?)$", REGEX_FLAGS_SI);
private static final Pattern P_QUOTED_ATTRIBUTES = Pattern.compile("([a-z0-9]+)=([\"'])(.*?)\\2", REGEX_FLAGS_SI);
private static final Pattern P_UNQUOTED_ATTRIBUTES = Pattern.compile("([a-z0-9]+)(=)([^\"\\s']+)", REGEX_FLAGS_SI);
private static final Pattern P_PROTOCOL = Pattern.compile("^([^:]+):", REGEX_FLAGS_SI);
private static final Pattern P_ENTITY = Pattern.compile("&#(\\d+);?");
private static final Pattern P_ENTITY_UNICODE = Pattern.compile("&#x([0-9a-f]+);?");
private static final Pattern P_ENCODE = Pattern.compile("%([0-9a-f]{2});?");
private static final Pattern P_VALID_ENTITIES = Pattern.compile("&([^&;]*)(?=(;|&|$))");
private static final Pattern P_VALID_QUOTES = Pattern.compile("(>|^)([^<]+?)(<|$)", Pattern.DOTALL);
private static final Pattern P_END_ARROW = Pattern.compile("^>");
private static final Pattern P_BODY_TO_END = Pattern.compile("<([^>]*?)(?=<|$)");
private static final Pattern P_XML_CONTENT = Pattern.compile("(^|>)([^<]*?)(?=>)");
private static final Pattern P_STRAY_LEFT_ARROW = Pattern.compile("<([^>]*?)(?=<|$)");
private static final Pattern P_STRAY_RIGHT_ARROW = Pattern.compile("(^|>)([^<]*?)(?=>)");
private static final Pattern P_AMP = Pattern.compile("&");
private static final Pattern P_QUOTE = Pattern.compile("<");
private static final Pattern P_LEFT_ARROW = Pattern.compile("<");
private static final Pattern P_RIGHT_ARROW = Pattern.compile(">");
private static final Pattern P_BOTH_ARROWS = Pattern.compile("<>");
private static final String SS="#//";
/** @xxx could grow large... maybe use sesat's ReferenceMap */
private static final ConcurrentMap<String,Pattern> P_REMOVE_PAIR_BLANKS = new ConcurrentHashMap<String, Pattern>();
private static final ConcurrentMap<String,Pattern> P_REMOVE_SELF_BLANKS = new ConcurrentHashMap<String, Pattern>();
/** set of allowed html elements, along with allowed attributes for each element **/
private final Map<String, List<String>> vAllowed;
/** counts of open tags for each (allowable) html element **/
private final Map<String, Integer> vTagCounts = new HashMap<String, Integer>();
/** html elements which must always be self-closing (e.g. "<img />") **/
private final String[] vSelfClosingTags;
/** html elements which must always have separate opening and closing tags (e.g. "<b></b>") **/
private final String[] vNeedClosingTags;
/** set of disallowed html elements **/
private final String[] vDisallowed;
/** attributes which should be checked for valid protocols **/
private final String[] vProtocolAtts;
/** allowed protocols **/
private final String[] vAllowedProtocols;
/** tags which should be removed if they contain no content (e.g. "<b></b>" or "<b />") **/
private final String[] vRemoveBlanks;
/** entities allowed within html markup **/
private final String[] vAllowedEntities;
/** flag determining whether comments are allowed in input String. */
private final boolean stripComment;
private final boolean encodeQuotes;
private boolean vDebug = false;
/**
* flag determining whether to try to make tags when presented with "unbalanced"
* angle brackets (e.g. "<b text </b>" becomes "<b> text </b>"). If set to false,
* unbalanced angle brackets will be html escaped.
*/
private final boolean alwaysMakeTags;
/** Default constructor.
*
*/
public HtmlFilter() {
vAllowed = new HashMap<>();
final ArrayList<String> aAtts = new ArrayList<String>();
aAtts.add("href");
aAtts.add("target");
vAllowed.put("a", aAtts);
final ArrayList<String> imgAtts = new ArrayList<String>();
imgAtts.add("src");
imgAtts.add("width");
imgAtts.add("height");
imgAtts.add("alt");
vAllowed.put("img", imgAtts);
final ArrayList<String> noAtts = new ArrayList<String>();
vAllowed.put("b", noAtts);
vAllowed.put("strong", noAtts);
vAllowed.put("i", noAtts);
vAllowed.put("em", noAtts);
vSelfClosingTags = new String[]{"img"};
vNeedClosingTags = new String[]{"a", "b", "strong", "i", "em"};
vDisallowed = new String[]{};
/**no ftp*/
vAllowedProtocols = new String[]{"http", "mailto", "https"};
vProtocolAtts = new String[]{"src", "href"};
vRemoveBlanks = new String[]{"a", "b", "strong", "i", "em"};
vAllowedEntities = new String[]{"amp", "gt", "lt", "quot"};
stripComment = true;
encodeQuotes = true;
alwaysMakeTags = true;
}
/** Set debug flag to true. Otherwise use default settings. See the default constructor.
*
* @param debug turn debug on with a true argument
*/
public HtmlFilter(final boolean debug) {
this();
vDebug = debug;
}
/** Map-parameter configurable constructor.
*
* @param conf map containing configuration. keys match field names.
*/
@SuppressWarnings("unchecked")
public HtmlFilter(final Map<String,Object> conf) {
assert conf.containsKey("vAllowed") : "configuration requires vAllowed";
assert conf.containsKey("vSelfClosingTags") : "configuration requires vSelfClosingTags";
assert conf.containsKey("vNeedClosingTags") : "configuration requires vNeedClosingTags";
assert conf.containsKey("vDisallowed") : "configuration requires vDisallowed";
assert conf.containsKey("vAllowedProtocols") : "configuration requires vAllowedProtocols";
assert conf.containsKey("vProtocolAtts") : "configuration requires vProtocolAtts";
assert conf.containsKey("vRemoveBlanks") : "configuration requires vRemoveBlanks";
assert conf.containsKey("vAllowedEntities") : "configuration requires vAllowedEntities";
vAllowed = Collections.unmodifiableMap((HashMap<String, List<String>>) conf.get("vAllowed"));
vSelfClosingTags = (String[]) conf.get("vSelfClosingTags");
vNeedClosingTags = (String[]) conf.get("vNeedClosingTags");
vDisallowed = (String[]) conf.get("vDisallowed");
vAllowedProtocols = (String[]) conf.get("vAllowedProtocols");
vProtocolAtts = (String[]) conf.get("vProtocolAtts");
vRemoveBlanks = (String[]) conf.get("vRemoveBlanks");
vAllowedEntities = (String[]) conf.get("vAllowedEntities");
stripComment = conf.containsKey("stripComment") ? (Boolean) conf.get("stripComment") : true;
encodeQuotes = conf.containsKey("encodeQuotes") ? (Boolean) conf.get("encodeQuotes") : true;
alwaysMakeTags = conf.containsKey("alwaysMakeTags") ? (Boolean) conf.get("alwaysMakeTags") : true;
}
private void reset() {
vTagCounts.clear();
}
private void debug(final String msg) {
if (vDebug) {
Logger.getAnonymousLogger().info(msg);
}
}
//---------------------------------------------------------------
/**my versions of some PHP library functions*/
public static String chr(final int decimal) {
return String.valueOf((char) decimal);
}
public static String htmlSpecialChars(final String s) {
String result = s;
result = regexReplace(P_AMP, "&", result);
result = regexReplace(P_QUOTE, """, result);
result = regexReplace(P_LEFT_ARROW, "<", result);
result = regexReplace(P_RIGHT_ARROW, ">", result);
return result;
}
//---------------------------------------------------------------
/**
* given a user submitted input String, filter out any invalid or restricted
* html.
*
* @param input text (i.e. submitted by a user) than may contain html
* @return "clean" version of input, with only valid, whitelisted html elements allowed
*/
public String filter(final String input) {
reset();
String s = input;
debug("************************************************");
debug(" INPUT: " + input);
s = escapeComments(s);
debug(" escapeComments: " + s);
s = balanceHTML(s);
debug(" balanceHTML: " + s);
s = checkTags(s);
debug(" checkTags: " + s);
s = processRemoveBlanks(s);
debug("processRemoveBlanks: " + s);
s = validateEntities(s);
debug(" validateEntites: " + s);
debug("************************************************\n\n");
return s;
}
public boolean isAlwaysMakeTags(){
return alwaysMakeTags;
}
public boolean isStripComments(){
return stripComment;
}
private String escapeComments(final String s) {
final Matcher m = P_COMMENTS.matcher(s);
final StringBuffer buf = new StringBuffer();
if (m.find()) {
/**(.*?)*/
final String match = m.group(1);
m.appendReplacement(buf, Matcher.quoteReplacement("<!--" + htmlSpecialChars(match) + "-->"));
}
m.appendTail(buf);
return buf.toString();
}
private String balanceHTML(String s) {
if (alwaysMakeTags) {
//
// try and form html
//
s = regexReplace(P_END_ARROW, "", s);
s = regexReplace(P_BODY_TO_END, "<$1>", s);
s = regexReplace(P_XML_CONTENT, "$1<$2", s);
} else {
//
// escape stray brackets
//
s = regexReplace(P_STRAY_LEFT_ARROW, "<$1", s);
s = regexReplace(P_STRAY_RIGHT_ARROW, "$1$2><", s);
//
// the last regexp causes '<>' entities to appear
// (we need to do a lookahead assertion so that the last bracket can
// be used in the next pass of the regexp)
//
s = regexReplace(P_BOTH_ARROWS, "", s);
}
return s;
}
private String checkTags(String s) {
Matcher m = P_TAGS.matcher(s);
final StringBuffer buf = new StringBuffer();
while (m.find()) {
String replaceStr = m.group(1);
replaceStr = processTag(replaceStr);
m.appendReplacement(buf, Matcher.quoteReplacement(replaceStr));
}
m.appendTail(buf);
s = buf.toString();
// these get tallied in processTag
// (remember to reset before subsequent calls to filter method)
for (String key : vTagCounts.keySet()) {
for (int ii = 0; ii < vTagCounts.get(key); ii++) {
s += "</" + key + ">";
}
}
return s;
}
private String processRemoveBlanks(final String s) {
String result = s;
for (String tag : vRemoveBlanks) {
if(!P_REMOVE_PAIR_BLANKS.containsKey(tag)){
P_REMOVE_PAIR_BLANKS.putIfAbsent(tag, Pattern.compile("<" + tag + "(\\s[^>]*)?></" + tag + ">"));
}
result = regexReplace(P_REMOVE_PAIR_BLANKS.get(tag), "", result);
if(!P_REMOVE_SELF_BLANKS.containsKey(tag)){
P_REMOVE_SELF_BLANKS.putIfAbsent(tag, Pattern.compile("<" + tag + "(\\s[^>]*)?/>"));
}
result = regexReplace(P_REMOVE_SELF_BLANKS.get(tag), "", result);
}
return result;
}
private static String regexReplace(final Pattern regexPattern, final String replacement, final String s) {
Matcher m = regexPattern.matcher(s);
return m.replaceAll(replacement);
}
private String processTag(final String s) {
// ending tags
Matcher m = P_END_TAG.matcher(s);
if (m.find()) {
final String name = m.group(1).toLowerCase();
if (allowed(name)) {
if (!inArray(name, vSelfClosingTags)) {
if (vTagCounts.containsKey(name)) {
vTagCounts.put(name, vTagCounts.get(name) - 1);
return "</" + name + ">";
}
}
}
}
// starting tags
m = P_START_TAG.matcher(s);
if (m.find()) {
final String name = m.group(1).toLowerCase();
final String body = m.group(2);
String ending = m.group(3);
//debug( "in a starting tag, name='" + name + "'; body='" + body + "'; ending='" + ending + "'" );
if (allowed(name)) {
String params = "";
final Matcher m2 = P_QUOTED_ATTRIBUTES.matcher(body);
final Matcher m3 = P_UNQUOTED_ATTRIBUTES.matcher(body);
final List<String> paramNames = new ArrayList<String>();
final List<String> paramValues = new ArrayList<String>();
while (m2.find()) {
/**([a-z0-9]+)*/
paramNames.add(m2.group(1));
/**(.*?)*/
paramValues.add(m2.group(3));
}
while (m3.find()) {
/**([a-z0-9]+)*/
paramNames.add(m3.group(1));
/**([^\"\\s']+)*/
paramValues.add(m3.group(3));
}
String paramName, paramValue;
for (int ii = 0; ii < paramNames.size(); ii++) {
paramName = paramNames.get(ii).toLowerCase();
paramValue = paramValues.get(ii);
if (allowedAttribute(name, paramName)) {
if (inArray(paramName, vProtocolAtts)) {
paramValue = processParamProtocol(paramValue);
}
params += " " + paramName + "=\"" + paramValue + "\"";
}
}
if (inArray(name, vSelfClosingTags)) {
ending = " /";
}
if (inArray(name, vNeedClosingTags)) {
ending = "";
}
if (ending == null || ending.length() < 1) {
if (vTagCounts.containsKey(name)) {
vTagCounts.put(name, vTagCounts.get(name) + 1);
} else {
vTagCounts.put(name, 1);
}
} else {
ending = " /";
}
return "<" + name + params + ending + ">";
} else {
return "";
}
}
// comments
m = P_COMMENT.matcher(s);
if (!stripComment && m.find()) {
return "<" + m.group() + ">";
}
return "";
}
private String processParamProtocol(String s) {
s = decodeEntities(s);
final Matcher m = P_PROTOCOL.matcher(s);
if (m.find()) {
final String protocol = m.group(1);
if (!inArray(protocol, vAllowedProtocols)) {
// bad protocol, turn into local anchor link instead
s = "#" + s.substring(protocol.length() + 1, s.length());
if (s.startsWith(SS)) {
s = "#" + s.substring(3, s.length());
}
}
}
return s;
}
private String decodeEntities(String s) {
StringBuffer buf = new StringBuffer();
Matcher m = P_ENTITY.matcher(s);
while (m.find()) {
final String match = m.group(1);
final int decimal = Integer.decode(match).intValue();
m.appendReplacement(buf, Matcher.quoteReplacement(chr(decimal)));
}
m.appendTail(buf);
s = buf.toString();
buf = new StringBuffer();
m = P_ENTITY_UNICODE.matcher(s);
while (m.find()) {
final String match = m.group(1);
final int decimal = Integer.valueOf(match, 16).intValue();
m.appendReplacement(buf, Matcher.quoteReplacement(chr(decimal)));
}
m.appendTail(buf);
s = buf.toString();
buf = new StringBuffer();
m = P_ENCODE.matcher(s);
while (m.find()) {
final String match = m.group(1);
final int decimal = Integer.valueOf(match, 16).intValue();
m.appendReplacement(buf, Matcher.quoteReplacement(chr(decimal)));
}
m.appendTail(buf);
s = buf.toString();
s = validateEntities(s);
return s;
}
private String validateEntities(final String s) {
StringBuffer buf = new StringBuffer();
// validate entities throughout the string
Matcher m = P_VALID_ENTITIES.matcher(s);
while (m.find()) {
/**([^&;]*)*/
final String one = m.group(1);
/**(?=(;|&|$))*/
final String two = m.group(2);
m.appendReplacement(buf, Matcher.quoteReplacement(checkEntity(one, two)));
}
m.appendTail(buf);
return encodeQuotes(buf.toString());
}
private String encodeQuotes(final String s){
if(encodeQuotes){
StringBuffer buf = new StringBuffer();
Matcher m = P_VALID_QUOTES.matcher(s);
while (m.find()) {
/**(>|^)*/
final String one = m.group(1);
/**([^<]+?)*/
final String two = m.group(2);
/**(<|$)*/
final String three = m.group(3);
m.appendReplacement(buf, Matcher.quoteReplacement(one + regexReplace(P_QUOTE, """, two) + three));
}
m.appendTail(buf);
return buf.toString();
}else{
return s;
}
}
private String checkEntity(final String preamble, final String term) {
return ";".equals(term) && isValidEntity(preamble)
? '&' + preamble
: "&" + preamble;
}
private boolean isValidEntity(final String entity) {
return inArray(entity, vAllowedEntities);
}
private static boolean inArray(final String s, final String[] array) {
for (String item : array) {
if (item != null && item.equals(s)) {
return true;
}
}
return false;
}
private boolean allowed(final String name) {
return (vAllowed.isEmpty() || vAllowed.containsKey(name)) && !inArray(name, vDisallowed);
}
private boolean allowedAttribute(final String name, final String paramName) {
return allowed(name) && (vAllowed.isEmpty() || vAllowed.get(name).contains(paramName));
}
}
敏感詞過濾工具類
import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Serializable;
import java.util.*;
import org.springframework.core.io.ClassPathResource;
/**
* Title: SensitiveWordUtils
* @author: gaodeqiang
* @date 2018年12月12日
* @version V1.0
* Description: 敏感詞過濾
*/
@SuppressWarnings("all")
public class SensitiveWordUtils implements Serializable {
private static final long serialVersionUID = 1L;
private SensitiveWordUtils() {
}
private static SensitiveWordUtils sensitiveWordUtils = null;
public synchronized static SensitiveWordUtils getSensitiveWordUtils() {
if (sensitiveWordUtils == null) {
sensitiveWordUtils = new SensitiveWordUtils();
}
return sensitiveWordUtils;
}
private static Set<String> sensitiveWordSet = null;
static {
try {
readResource("keywords.txt");
} catch (Exception e) {
e.printStackTrace();
}
// 初始化敏感詞庫
initSensitiveWordMap();
}
private static final int MinMatchTYpe = 1; // 最小匹配規則，如：敏感詞庫["中國","中國人"]，語句："我是中國人"，匹配結果：我是[中國]人
private static final int MaxMatchType = 2; // 最大匹配規則，如：敏感詞庫["中國","中國人"]，語句："我是中國人"，匹配結果：我是[中國人]
private static HashMap sensitiveWordMap = new HashMap<>();
/**
* @author gaodeqiang
* @Description 讀取資源文件
* @date 2018年12月13日上午9:29:01
*/
private static void readResource(String name) throws Exception {
ClassPathResource resource = new ClassPathResource(name);
InputStream inputStream = resource.getInputStream();
InputStreamReader read = new InputStreamReader(inputStream, "utf-8");
// 初始化set集合
sensitiveWordSet = new HashSet<String>();
// 緩沖區讀取流
BufferedReader bufferedReader = new BufferedReader(read);
// 循環讀取文件中內容，每次讀取一行內容
String txt = null;
while ((txt = bufferedReader.readLine()) != null) {
// 讀取文件，將文件內容放入到set中
sensitiveWordSet.add(txt);
}
read.close();
}
/**
* @author gaodeqiang
* @Description 初始化敏感詞庫，構建DFA算法模型
* @date 2018年12月13日上午9:30:08
*/
private static void initSensitiveWordMap() {
// 初始化敏感詞容器，減少擴容操作
sensitiveWordMap = new HashMap(sensitiveWordSet.size());
String key;
Map nowMap;
Map<String, String> newWorMap;
// 迭代sensitiveWordSet
Iterator<String> iterator = sensitiveWordSet.iterator();
while (iterator.hasNext()) {
// 關鍵字
key = iterator.next();
nowMap = sensitiveWordMap;
for (int i = 0; i < key.length(); i++) {
// 轉換成char型
char keyChar = key.charAt(i);
// 庫中獲取關鍵字
Object wordMap = nowMap.get(keyChar);
// 如果存在該key，直接賦值，用於下一個循環獲取
if (wordMap != null) {
nowMap = (Map) wordMap;
} else {
// 不存在則，則構建一個map，同時將isEnd設置為0，因為他不是最後一個
newWorMap = new HashMap<>();
// 不是最後一個
newWorMap.put("isEnd", "0");
nowMap.put(keyChar, newWorMap);
nowMap = newWorMap;
}
if (i == key.length() - 1) {
// 最後一個
nowMap.put("isEnd", "1");
}
}
}
}
/**
* @author gaodeqiang
* @Description 檢查文字中是否包含敏感字符
* @date 2018年12月13日上午9:38:35
*/
private int checkSensitiveWord(String txt, int beginIndex, int matchType) {
// 敏感詞結束標識位：用於敏感詞隻有1位的情況
boolean flag = false;
// 匹配標識數默認為0
int matchFlag = 0;
char word;
Map nowMap = sensitiveWordMap;
for (int i = beginIndex; i < txt.length(); i++) {
word = txt.charAt(i);
// 獲取指定key
nowMap = (Map) nowMap.get(word);
if (nowMap != null) {// 存在，則判斷是否為最後一個
// 找到相應key，匹配標識+1
matchFlag++;
// 如果為最後一個匹配規則,結束循環，返回匹配標識數
if ("1".equals(nowMap.get("isEnd"))) {
// 結束標志位為true
flag = true;
// 最小規則，直接返回,最大規則還需繼續查找
if (MinMatchTYpe == matchType) {
break;
}
}
} else {// 不存在，直接返回
break;
}
}
if (matchFlag < 2 || !flag) {// 長度必須大於等於1，為詞
matchFlag = 0;
}
return matchFlag;
}
/**
* @author gaodeqiang
* @Description 判斷文字是否包含敏感字符 匹配規則 1：最小匹配規則，2：最大匹配規則
* @date 2018年12月13日上午9:34:23
*/
public boolean contains(String txt, int matchType) {
boolean flag = false;
for (int i = 0; i < txt.length(); i++) {
int matchFlag = checkSensitiveWord(txt, i, matchType); // 判斷是否包含敏感字符
if (matchFlag > 0) { // 大於0存在，返回true
flag = true;
}
}
return flag;
}
/**
* @author gaodeqiang
* @Description 獲取文字中的敏感詞
* @date 2018年12月13日上午9:36:00
*/
public Set<String> getSensitiveWord(String txt, int matchType) {
Set<String> sensitiveWordList = new HashSet<>();
for (int i = 0; i < txt.length(); i++) {
// 判斷是否包含敏感字符
int length = checkSensitiveWord(txt, i, matchType);
if (length > 0) {// 存在,加入list中
sensitiveWordList.add(txt.substring(i, i + length));
i = i + length - 1;// 減1的原因，是因為for會自增
}
}
return sensitiveWordList;
}
/**
* @author gaodeqiang
* @Description 替換敏感字字符
* @date 2018年12月13日上午9:36:34
*/
public String replaceSensitiveWord(String txt, char replaceChar, int matchType) {
String resultTxt = txt;
// 獲取所有的敏感詞
Set<String> set = getSensitiveWord(txt, matchType);
Iterator<String> iterator = set.iterator();
String word;
String replaceString;
while (iterator.hasNext()) {
word = iterator.next();
replaceString = getReplaceChars(replaceChar, word.length());
resultTxt = resultTxt.replaceAll(word, replaceString);
}
return resultTxt;
}
/**
* @author gaodeqiang
* @Description 獲取替換字符串
* @date 2018年12月13日上午9:37:53
*/
private String getReplaceChars(char replaceChar, int length) {
String resultReplace = String.valueOf(replaceChar);
for (int i = 1; i < length; i++) {
resultReplace += replaceChar;
}
return resultReplace;
}
}
以上為個人經驗，希望能給大傢一個參考，也希望大傢多多支持WalkonNet。
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