jodd.servlet.ServletUtil Maven / Gradle / Ivy
// Copyright (c) 2003-2011, Jodd Team (jodd.org). All Rights Reserved.
package jodd.servlet;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.File;
import java.io.StringWriter;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Map;
import javax.servlet.ServletRequest;
import javax.servlet.ServletContext;
import javax.servlet.jsp.PageContext;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import jodd.io.StreamUtil;
import jodd.util.Base64;
import jodd.util.StringPool;
import jodd.util.MimeTypes;
import jodd.io.FileNameUtil;
import jodd.servlet.upload.MultipartRequestWrapper;
import jodd.servlet.upload.FileUpload;
import jodd.util.StringUtil;
/**
* Miscellaneous servlet utilities.
*/
public class ServletUtil {
public static final String HEADER_CONTENT_TYPE = "Content-Type";
public static final String TYPE_MULTIPART_FORM_DATA = "multipart/form-data";
public static final String HEADER_AUTHORIZATION = "Authorization";
public static final String CONTENT_DISPOSITION = "Content-Disposition";
public static final String WWW_AUTHENTICATE = "WWW-Authenticate";
private static final String JAVAX_SERVLET_ERROR_EXCEPTION = "javax.servlet.error.exception";
public static final String METHOD_GET = "GET";
public static final String METHOD_HEAD = "HEAD";
public static final String METHOD_PUT = "PUT";
public static final String METHOD_POST = "POST";
public static final String METHOD_DELETE = "DELETE";
public static final String METHOD_OPTIONS = "OPTIONS";
public static final String METHOD_TRACE = "TRACE";
public static final String METHOD_CONNECT = "CONNECT";
// ---------------------------------------------------------------- multi-part
/**
* Returns true if a request is multi-part request.
*/
public static boolean isMultipartRequest(HttpServletRequest request) {
String type = request.getHeader(HEADER_CONTENT_TYPE);
return (type != null) && type.startsWith(TYPE_MULTIPART_FORM_DATA);
}
/**
* Sets the "Vary response header" to User-Agent to indicate that the page content
* varies depending on which user agent (browser) is being used.
*/
public static void setBrowserVary(HttpServletResponse response) {
response.setHeader( "Vary", "User-Agent");
}
// ---------------------------------------------------------------- authorization
/**
* Decodes the "Authorization" header and retrieves the
* user's name from it. Returns null if the header is not present.
*/
public static String getAuthUsername(HttpServletRequest request) {
String header = request.getHeader(HEADER_AUTHORIZATION);
if (header == null) {
return null;
}
String encoded = header.substring(header.indexOf(' ') + 1);
String decoded = new String(Base64.decode(encoded));
return decoded.substring(0, decoded.indexOf(':'));
}
/**
* Decodes the "Authorization" header and retrieves the
* password from it. Returns null if the header is not present.
*/
public static String getAuthPassword(HttpServletRequest request) {
String header = request.getHeader(HEADER_AUTHORIZATION);
if (header == null) {
return null;
}
String encoded = header.substring(header.indexOf(' ') + 1);
String decoded = new String(Base64.decode(encoded));
return decoded.substring(decoded.indexOf(':') + 1);
}
/**
* Sends correct headers to require basic authentication for the given realm.
*/
public static void requireAuthentication(HttpServletResponse resp, String realm) throws IOException {
resp.setHeader(WWW_AUTHENTICATE, "Basic realm=\"" + realm + '\"');
resp.sendError(HttpServletResponse.SC_UNAUTHORIZED);
}
// ---------------------------------------------------------------- content disposition
/**
* Prepares response for file download when file size is not known.
* @see #prepareDownload(javax.servlet.http.HttpServletResponse, String, int)
*/
public static void prepareDownload(HttpServletResponse response, String fileName) {
prepareDownload(response, fileName, -1);
}
/**
* Prepares response for file download. Sets correct mime type, file name and file size.
*/
public static void prepareDownload(HttpServletResponse response, String fileName, int fileSize) {
String extension = FileNameUtil.getExtension(fileName);
String name = FileNameUtil.getName(fileName);
String mime = MimeTypes.getMimeType(extension);
response.setContentType(mime);
response.setHeader(CONTENT_DISPOSITION,"attachment;filename=\"" + name + '\"');
if (fileSize >= 0) {
response.setContentLength(fileSize);
}
}
/**
* Prepares response for file download.
*/
public static void prepareDownload(HttpServletResponse response, File file) {
if (file.exists() == false) {
throw new IllegalArgumentException("Unable to prepare file for download. File '" + file + "' doesn't exist.");
}
if (file.length() > Integer.MAX_VALUE) {
throw new IllegalArgumentException("Unable to prepare file for download. File '" + file + "' is too big.");
}
prepareDownload(response, file.getAbsolutePath(), (int) file.length());
}
// ---------------------------------------------------------------- cookie
/**
* Finds and returns cookie from client by its name.
* Only the first cookie is returned.
* @see #getAllCookies(javax.servlet.http.HttpServletRequest, String)
* @return cookie value or null if cookie with specified name doesn't exist.
*/
public static Cookie getCookie(HttpServletRequest request, String cookieName) {
Cookie[] cookies = request.getCookies();
if (cookies != null) {
for (Cookie cookie : cookies) {
if (cookie.getName().equals(cookieName)) {
return cookie;
}
}
}
return null;
}
/**
* Returns all cookies from client that matches provided name.
* @see #getCookie(javax.servlet.http.HttpServletRequest, String)
*/
public static Cookie[] getAllCookies(HttpServletRequest request, String cookieName) {
Cookie[] cookies = request.getCookies();
if (cookies == null) {
return null;
}
ArrayList list = new ArrayList(cookies.length);
for (Cookie cookie : cookies) {
if (cookie.getName().equals(cookieName)) {
list.add(cookie);
}
}
if (list.isEmpty()) {
return null;
}
return list.toArray(new Cookie[list.size()]);
}
// ---------------------------------------------------------------- request body
/**
* Reads HTTP request body. Useful only with POST requests. Once body is read,
* it cannot be read again!
*/
public static String readRequestBody(HttpServletRequest request) throws IOException {
BufferedReader buff = request.getReader();
StringWriter out = new StringWriter();
StreamUtil.copy(buff, out);
return out.toString();
}
// ---------------------------------------------------------------- request/session
/**
* Returns correct context path, as by Servlet definition. Different
* application servers return all variants: "", null, "/".
*
* The context path always comes first in a request URI. The path
* starts with a "/" character but does not end with a "/" character.
* For servlets in the default (root) context, this method returns "".
*/
public static String getContextPath(HttpServletRequest request) {
String contextPath = request.getContextPath();
if (contextPath == null || contextPath.equals(StringPool.SLASH)) {
contextPath = StringPool.EMPTY;
}
return contextPath;
}
/**
* Returns correct context path, as by Servlet definition. Different
* application servers return all variants: "", null, "/".
*
* The context path always comes first in a request URI. The path
* starts with a "/" character but does not end with a "/" character.
* For servlets in the default (root) context, this method returns "".
*/
public static String getContextPath(ServletContext servletContext) {
String contextPath = servletContext.getContextPath();
if (contextPath == null || contextPath.equals(StringPool.SLASH)) {
contextPath = StringPool.EMPTY;
}
return contextPath;
}
/**
* Returns HTTP request parameter as String or String[].
*/
public static Object getRequestParameter(ServletRequest request, String name) {
String[] values = request.getParameterValues(name);
if (values == null) {
return null;
}
if (values.length == 1) {
return values[0];
}
return values;
}
/**
* Transfers attributes from provided map to the request.
*/
public static void setRequestAttributes(ServletRequest request, Map attributes) {
for (Map.Entry entry : attributes.entrySet()) {
request.setAttribute(entry.getKey(), entry.getValue());
}
}
/**
* Returns a new map containing request attributes.
*/
public static Map getRequestAttributes(ServletRequest request) {
Map map = new HashMap();
loadRequestAttributes(map, request);
return map;
}
/**
* Loads existing map with request attributes.
*/
public static void loadRequestAttributes(Map map, ServletRequest request) {
Enumeration names = request.getAttributeNames();
while (names.hasMoreElements()) {
String name = (String) names.nextElement();
map.put(name, request.getAttribute(name));
}
}
/**
* Returns a new map containing request parameters. Request parameter may
* be either String or String[].
* @see #getRequestParameter(ServletRequest, String)
*/
public static Map getRequestParameters(ServletRequest request) {
Map map = new HashMap();
loadRequestParameters(map, request);
return map;
}
public static void loadRequestParameters(Map map, ServletRequest request) {
Enumeration names = request.getParameterNames();
while (names.hasMoreElements()) {
String name = (String) names.nextElement();
map.put(name, getRequestParameter(request, name));
}
}
/**
* Loads session attributes into a map.
*/
public static void loadSessionAttributes(Map destination, HttpSession session) {
Enumeration names = session.getAttributeNames();
while (names.hasMoreElements()) {
String name = (String) names.nextElement();
destination.put(name, session.getAttribute(name));
}
}
public static Map getSessionAttributes(HttpSession session) {
Map map = new HashMap();
loadSessionAttributes(map, session);
return map;
}
public static void setSessionAttributes(HttpSession session, Map attributes) {
for (Map.Entry entry : attributes.entrySet()) {
session.setAttribute(entry.getKey(), entry.getValue());
}
}
// ---------------------------------------------------------------- get value
/**
* Returns non-null attribute value. Scopes are examined in the
* following order: page, request, session, application.
*/
public static Object attrValue(PageContext pageContext, String name) {
Object value = pageContext.getAttribute(name);
if (value != null) {
return value;
}
return attrValue((HttpServletRequest) pageContext.getRequest(), name);
}
/**
* Returns non-null attribute value. Scopes are examined in the
* following order: request, session, application.
*/
public static Object attrValue(HttpServletRequest request, String name) {
Object value = request.getAttribute(name);
if (value != null) {
return value;
}
value = request.getSession().getAttribute(name);
if (value != null) {
return value;
}
return request.getSession().getServletContext().getAttribute(name);
}
/**
* Returns non-null value of property/attribute. Scopes are examined in the following
* order: page (if exist), request, request parameters, session, application.
*/
public static Object value(PageContext pageContext, String name) {
Object value = pageContext.getAttribute(name);
if (value != null) {
return value;
}
return value((HttpServletRequest) pageContext.getRequest(), name);
}
/**
* Returns non-null value of property/attribute. Scopes are examined in the following
* order: page (if exist), request, request parameters, session, application.
*/
public static Object value(HttpServletRequest request, String name) {
Object value = request.getAttribute(name);
if (value != null) {
return value;
}
value = request.getParameter(name);
if (value != null) {
return value;
}
value = request.getSession().getAttribute(name);
if (value != null) {
return value;
}
return request.getSession().getServletContext().getAttribute(name);
}
// ---------------------------------------------------------------- resolve URL
/**
* Valid characters in a scheme, as specified by RFC 1738.
*/
public static final String VALID_SCHEME_CHARS = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789+.-";
/**
* Returns true if current URL is absolute, false otherwise.
*/
public static boolean isAbsoluteUrl(String url) {
if (url == null) { // a null URL is not absolute
return false;
}
int colonPos; // fast simple check first
if ((colonPos = url.indexOf(':')) == -1) {
return false;
}
// if we DO have a colon, make sure that every character
// leading up to it is a valid scheme character
for (int i = 0; i < colonPos; i++) {
if (VALID_SCHEME_CHARS.indexOf(url.charAt(i)) == -1) {
return false;
}
}
return true;
}
/**
* Strips a servlet session ID from url. The session ID
* is encoded as a URL "path parameter" beginning with "jsessionid=".
* We thus remove anything we find between ";jsessionid=" (inclusive)
* and either EOS or a subsequent ';' (exclusive).
*/
public static String stripSession(String url) {
StringBuilder u = new StringBuilder(url);
int sessionStart;
while ((sessionStart = u.toString().indexOf(";jsessionid=")) != -1) {
int sessionEnd = u.toString().indexOf(';', sessionStart + 1);
if (sessionEnd == -1) {
sessionEnd = u.toString().indexOf('?', sessionStart + 1);
}
if (sessionEnd == -1) {
sessionEnd = u.length();
}
u.delete(sessionStart, sessionEnd);
}
return u.toString();
}
public static String resolveUrl(String url, PageContext pageContext) {
return resolveUrl(url, (HttpServletRequest) pageContext.getRequest());
}
public static String resolveUrl(String url, HttpServletRequest request) {
if (isAbsoluteUrl(url)) {
return url;
}
if (url.startsWith(StringPool.SLASH)) {
return getContextPath(request) + url;
} else {
return url;
}
}
public static String resolveUrl(String url, String context) {
if (isAbsoluteUrl(url)) {
return url;
}
if (!context.startsWith(StringPool.SLASH) || !url.startsWith(StringPool.SLASH)) {
throw new IllegalArgumentException("Values of both 'context' and 'url' must start with '/'.");
}
if (context.equals(StringPool.SLASH)) {
return url;
} else {
return (context + url);
}
}
// ---------------------------------------------------------------- params
/**
* Checks if some parameter is in GET parameters.
*/
public boolean isGetParameter(HttpServletRequest request, String key) {
key = UrlEncoder.encode(key) + '=';
String query = request.getQueryString();
String[] nameValuePairs = StringUtil.splitc(query, '&');
for (String nameValuePair : nameValuePairs) {
if (nameValuePair.startsWith(key)) {
return true;
}
}
return false;
}
/**
* Prepares parameters for further processing.
* @param paramValues string array of param values
* @param trimParams trim parameters
* @param treatEmptyParamsAsNull empty parameters should be treated as null
* @param ignoreEmptyRequestParams if all parameters are empty, return null
*/
public static String[] prepareParameters(String[] paramValues, boolean trimParams, boolean treatEmptyParamsAsNull, boolean ignoreEmptyRequestParams) {
if (trimParams || treatEmptyParamsAsNull || ignoreEmptyRequestParams) {
int emptyCount = 0;
int total = paramValues.length;
for (int i = 0; i < paramValues.length; i++) {
String paramValue = paramValues[i];
if (paramValue == null) {
emptyCount++;
continue;
}
if (trimParams) {
paramValue = paramValue.trim();
}
if (paramValue.length() == 0) {
emptyCount++;
if (treatEmptyParamsAsNull) {
paramValue = null;
}
}
paramValues[i] = paramValue;
}
if ((ignoreEmptyRequestParams == true) && (emptyCount == total)) {
return null;
}
}
return paramValues;
}
// ---------------------------------------------------------------- copy
/**
* Copies all request parameters to attributes.
*/
public static void copyParamsToAttributes(HttpServletRequest servletRequest, boolean trimParams, boolean treatEmptyParamsAsNull, boolean ignoreEmptyRequestParams) {
Enumeration paramNames = servletRequest.getParameterNames();
while (paramNames.hasMoreElements()) {
String paramName = (String) paramNames.nextElement();
if (servletRequest.getAttribute(paramName) != null) {
continue;
}
String[] paramValues = servletRequest.getParameterValues(paramName);
paramValues = prepareParameters(paramValues, trimParams, treatEmptyParamsAsNull, ignoreEmptyRequestParams);
if (paramValues == null) {
continue;
}
servletRequest.setAttribute(paramName, paramValues.length == 1 ? paramValues[0] : paramValues);
}
// multipart
if ((servletRequest instanceof MultipartRequestWrapper) == false) {
return;
}
MultipartRequestWrapper multipartRequest = (MultipartRequestWrapper) servletRequest;
if (multipartRequest.isMultipart() == false) {
return;
}
paramNames = multipartRequest.getFileParameterNames();
while (paramNames.hasMoreElements()) {
String paramName = (String) paramNames.nextElement();
if (servletRequest.getAttribute(paramName) != null) {
continue;
}
FileUpload[] paramValues = multipartRequest.getFiles(paramName);
servletRequest.setAttribute(paramName, paramValues.length == 1 ? paramValues[0] : paramValues);
}
}
// ---------------------------------------------------------------- errors
/**
* Returns servlet error.
*/
public static Throwable getServletError(ServletRequest request) {
return (Throwable) request.getAttribute(JAVAX_SERVLET_ERROR_EXCEPTION);
}
/**
* Sets servlet error.
*/
public static void setServletError(ServletRequest request, Throwable throwable) {
request.setAttribute(JAVAX_SERVLET_ERROR_EXCEPTION, throwable);
}
// ---------------------------------------------------------------- debug
/**
* Returns a string with debug info from all servlet objects.
* @see #debug(HttpServletRequest, PageContext)
*/
public static String debug(HttpServletRequest request) {
return debug(request, null);
}
/**
* Returns a string with debug info from all servlet objects.
* @see #debug(HttpServletRequest, PageContext)
*/
public static String debug(PageContext pageContext) {
return debug((HttpServletRequest) pageContext.getRequest(), pageContext);
}
/**
* Returns a string with debug info from all servlet objects, including pageScope.
*/
protected static String debug(HttpServletRequest request, PageContext pageContext) {
StringBuilder result = new StringBuilder();
result.append("\nPARAMETERS\n----------\n");
Enumeration enumeration = request.getParameterNames();
while (enumeration.hasMoreElements()) {
String name = (String) enumeration.nextElement();
Object[] value = request.getParameterValues(name);
result.append(name).append('=');
if (value == null) {
result.append("");
} else if (value.length == 1) {
result.append(value[0]).append('\n');
} else {
result.append('[');
for (int i = 0, valueLength = value.length; i < valueLength; i++) {
if (i == 0) {
result.append(',');
}
result.append(value[i]);
}
result.append("]\n");
}
}
HttpSession session = request.getSession();
ServletContext context = session.getServletContext();
loop:
for (int i = 0; i < 4; i++) {
switch (i) {
case 0: result.append("\nREQUEST\n--------\n");
enumeration = request.getAttributeNames();
break;
case 1: result.append("\nSESSION\n--------\n");
enumeration = session.getAttributeNames();
break;
case 2: result.append("\nAPPLICATION\n-----------\n");
enumeration = context.getAttributeNames();
break;
case 3: if (pageContext == null) {
break loop;
}
result.append("\nPAGE\n-----------\n");
enumeration = pageContext.getAttributeNamesInScope(PageContext.PAGE_SCOPE);
}
while (enumeration.hasMoreElements()) {
String name = (String) enumeration.nextElement();
Object value = null;
switch (i) {
case 0: value = request.getAttribute(name); break;
case 1: value = session.getAttribute(name); break;
case 2: value = context.getAttribute(name); break;
case 3: value = pageContext.getAttribute(name); break;
}
result.append(name).append('=');
if (value == null) {
result.append("\n");
} else {
String stringValue;
try {
stringValue = value.toString();
} catch (Exception ignore) {
stringValue = "<" + value.getClass() + ">\n";
}
result.append(stringValue).append('\n');
}
}
}
return result.toString();
}
// ---------------------------------------------------------------- cache
/**
* Prevents HTTP cache.
*/
public static void preventCaching(HttpServletResponse response) {
response.setHeader("Cache-Control", "max-age=0, must-revalidate, no-cache, no-store, private, post-check=0, pre-check=0"); // HTTP 1.1
response.setHeader("Pragma","no-cache"); // HTTP 1.0
response.setDateHeader ("Expires", 0); // prevents caching at the proxy server
}
}