攔截器中讀取request中的流後，controller 無法獲取到資料解決方案
阿新 • • 發佈：2019-02-05
一般我們會在InterceptorAdapter攔截器中對請求的token進行驗證
如果是content-type 是 application/x-www-form-urlencoded 則沒有什麼問題
如果我們的介面是用@RequestBody來接受資料，那麼我們在攔截器中驗證token時
需要讀取request的輸入流 ，因為 ServletRequest中getReader()和getInputStream()只能呼叫一次
這樣就會導致controller 無法拿到資料。
解決方法 ：
自定義一個類 BodyReaderHttpServletRequestWrapper.java
import java.io.BufferedInputStream; import java.io.BufferedReader; import java.io.ByteArrayInputStream; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.io.UnsupportedEncodingException; import java.net.URLDecoder; import java.util.Collections; import java.util.Enumeration; import java.util.HashMap; import java.util.Map; import java.util.StringTokenizer; import javax.servlet.ReadListener; import javax.servlet.ServletInputStream; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletRequestWrapper; import com.microdata.core.util.Encodes; public class BodyReaderHttpServletRequestWrapper extends HttpServletRequestWrapper { private Map<String, String[]> paramsMap; @Override public Map getParameterMap() { return paramsMap; } @Override public String getParameter(String name) {// 重寫getParameter，代表引數從當前類中的map獲取 String[] values = paramsMap.get(name); if (values == null || values.length == 0) { return null; } return values[0]; } @Override public String[] getParameterValues(String name) {// 同上 return paramsMap.get(name); } @Override public Enumeration getParameterNames() { return Collections.enumeration(paramsMap.keySet()); } private String getRequestBody(InputStream stream) { String line = ""; StringBuilder body = new StringBuilder(); int counter = 0; // 讀取POST提交的資料內容 BufferedReader reader = new BufferedReader(new InputStreamReader(stream)); try { while ((line = reader.readLine()) != null) { if (counter > 0) { body.append("rn"); } body.append(line); counter++; } } catch (IOException e) { e.printStackTrace(); } return body.toString(); } private HashMap<String, String[]> getParamMapFromPost(HttpServletRequest request) { String body = ""; try { body = getRequestBody(request.getInputStream()); } catch (IOException e) { e.printStackTrace(); } HashMap<String, String[]> result = new HashMap<String, String[]>(); if (null == body || 0 == body.length()) { return result; } return parseQueryString(body); } // 自定義解碼函式 private String decodeValue(String value) { if (value.contains("%u")) { return Encodes.urlDecode(value); } else { try { return URLDecoder.decode(value, "UTF-8"); } catch (UnsupportedEncodingException e) { return "";// 非UTF-8編碼 } } } public HashMap<String, String[]> parseQueryString(String s) { String valArray[] = null; if (s == null) { throw new IllegalArgumentException(); } HashMap<String, String[]> ht = new HashMap<String, String[]>(); StringTokenizer st = new StringTokenizer(s, "&"); while (st.hasMoreTokens()) { String pair = (String) st.nextToken(); int pos = pair.indexOf('='); if (pos == -1) { continue; } String key = pair.substring(0, pos); String val = pair.substring(pos + 1, pair.length()); if (ht.containsKey(key)) { String oldVals[] = (String[]) ht.get(key); valArray = new String[oldVals.length + 1]; for (int i = 0; i < oldVals.length; i++) { valArray[i] = oldVals[i]; } valArray[oldVals.length] = decodeValue(val); } else { valArray = new String[1]; valArray[0] = decodeValue(val); } ht.put(key, valArray); } return ht; } private Map<String, String[]> getParamMapFromGet(HttpServletRequest request) { return parseQueryString(request.getQueryString()); } private final byte[] body; // 報文 public BodyReaderHttpServletRequestWrapper(HttpServletRequest request) throws IOException { super(request); body = readBytes(request.getInputStream()); // 首先從POST中獲取資料 if ("POST".equals(request.getMethod().toUpperCase())) { paramsMap = getParamMapFromPost(this); } else { paramsMap = getParamMapFromGet(this); } } @Override public BufferedReader getReader() throws IOException { return new BufferedReader(new InputStreamReader(getInputStream())); } @Override public ServletInputStream getInputStream() throws IOException { final ByteArrayInputStream bais = new ByteArrayInputStream(body); return new ServletInputStream() { @Override public int read() throws IOException { return bais.read(); } @Override public boolean isFinished() { return false; } @Override public boolean isReady() { return false; } @Override public void setReadListener(ReadListener arg0) { } }; } private static byte[] readBytes(InputStream in) throws IOException { BufferedInputStream bufin = new BufferedInputStream(in); int buffSize = 1024; ByteArrayOutputStream out = new ByteArrayOutputStream(buffSize); byte[] temp = new byte[buffSize]; int size = 0; while ((size = bufin.read(temp)) != -1) { out.write(temp, 0, size); } bufin.close(); byte[] content = out.toByteArray(); return content; } }
自定義Filter HttpServletRequestReplacedFilter.java
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; import com.microdata.core.request.BodyReaderHttpServletRequestWrapper; public class HttpServletRequestReplacedFilter implements Filter { @Override public void destroy() { } @Override public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException { ServletRequest requestWrapper = null; if (request instanceof HttpServletRequest) { HttpServletRequest httpServletRequest = (HttpServletRequest) request; if ("POST".equals(httpServletRequest.getMethod().toUpperCase()) && httpServletRequest.getContentType().equalsIgnoreCase( "application/json; charset=utf-8")) { requestWrapper = new BodyReaderHttpServletRequestWrapper( (HttpServletRequest) request); } } if (requestWrapper == null) { chain.doFilter(request, response); } else { chain.doFilter(requestWrapper, response); } } @Override public void init(FilterConfig arg0) throws ServletException { } }
在web.xml 配置
<filter>
<filter-name>HttpServletRequestReplacedFilter</filter-name>
<filter-class>com.microdata.core.filter.HttpServletRequestReplacedFilter</filter-class>
<init-param>
<param-name>encoding</param-name>
<param-value>utf-8</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>HttpServletRequestReplacedFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>Encodes 類
package com.microdata.core.util;
import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;
import java.net.URLEncoder;
import org.apache.commons.codec.DecoderException;
import org.apache.commons.codec.binary.Base64;
import org.apache.commons.codec.binary.Hex;
import org.apache.commons.lang3.StringEscapeUtils;
/**
* 封裝各種格式的編碼解碼工具類.
*
* 1.Commons-Codec的 hex/base64 編碼
* 2.自制的base62 編碼
* 3.Commons-Lang的xml/html escape
* 4.JDK提供的URLEncoder
*
*/
public class Encodes {
private static final String DEFAULT_URL_ENCODING = "UTF-8";
private static final char[] BASE62 = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz".toCharArray();
/**
* Hex編碼.
*/
public static String encodeHex(byte[] input) {
return Hex.encodeHexString(input);
}
/**
* Hex解碼.
*/
public static byte[] decodeHex(String input) {
try {
return Hex.decodeHex(input.toCharArray());
} catch (DecoderException e) {
throw Exceptions.unchecked(e);
}
}
/**
* Base64編碼.
*/
public static String encodeBase64(byte[] input) {
return Base64.encodeBase64String(input);
}
/**
* Base64編碼, URL安全(將Base64中的URL非法字元'+'和'/'轉為'-'和'_', 見RFC3548).
*/
public static String encodeUrlSafeBase64(byte[] input) {
return Base64.encodeBase64URLSafeString(input);
}
/**
* Base64解碼.
*/
public static byte[] decodeBase64(String input) {
return Base64.decodeBase64(input);
}
/**
* Base62編碼。
*/
public static String encodeBase62(byte[] input) {
char[] chars = new char[input.length];
for (int i = 0; i < input.length; i++) {
chars[i] = BASE62[(input[i] & 0xFF) % BASE62.length];
}
return new String(chars);
}
/**
* Html 轉碼.
*/
public static String escapeHtml(String html) {
return StringEscapeUtils.escapeHtml4(html);
}
/**
* Html 解碼.
*/
public static String unescapeHtml(String htmlEscaped) {
return StringEscapeUtils.unescapeHtml4(htmlEscaped);
}
/**
* Xml 轉碼.
*/
public static String escapeXml(String xml) {
return StringEscapeUtils.escapeXml(xml);
}
/**
* Xml 解碼.
*/
public static String unescapeXml(String xmlEscaped) {
return StringEscapeUtils.unescapeXml(xmlEscaped);
}
/**
* URL 編碼, Encode預設為UTF-8.
*/
public static String urlEncode(String part) {
try {
return URLEncoder.encode(part, DEFAULT_URL_ENCODING);
} catch (UnsupportedEncodingException e) {
throw Exceptions.unchecked(e);
}
}
/**
* URL 解碼, Encode預設為UTF-8.
*/
public static String urlDecode(String part) {
try {
return URLDecoder.decode(part, DEFAULT_URL_ENCODING);
} catch (UnsupportedEncodingException e) {
throw Exceptions.unchecked(e);
}
}
}