A simple JSP Tag Library to display the code, reason, cause and/or message for HTTP status codes in JSP error pages.
For example:
<%@ page isErrorPage="true" %>
<%@ taglib prefix="hs" uri="http://erik.thauvin.net/taglibs/httpstatus" %>
<html><head>
<title><hs:code/> <hs:reason default="Server Error"/></title>
</head>
<h1><hs:reason default="Server Error"/></h1>
Cause: <pre><hs:cause default="Unable to complete your request."/></pre>
Message: <pre><hs:message default="A server error has occured."/></pre>
...or
<%@ page isErrorPage="true" import="net.thauvin.erik.httpstatus.Reasons" %>
<%= Reasons.getReasonPhrase(pageContext.getErrorData().getStatusCode()) %>would display on a 501 status code:
Not ImplementedInclude the following in your build.gradle file:
repositories {
mavenCentral()
}
dependencies {
implementation 'net.thauvin.erik.httpstatus:httpstatus:1.1.1'
}Include the following in your bld build file:
scope(compile).include(
dependency("net.thauvin.erik.httpstatus","httpstatus", version(1, 1, 0))
);As a Maven artifact:
<dependency>
<groupId>net.thauvin.erik.httpstatus</groupId>
<artifactId>httpstatus</artifactId>
<version>1.1.1</version>
</dependency>The <hs:cause/> tag displays the cause of current HTTP status code, if any. A shorthand for:
<%= pageContext.getErrorData().getThrowable().getCause().getLocalizedMessage() %>Optional attributes are:
| Attribute | Description |
|---|---|
default |
The fallback value to output, if no cause is |
escapeXml |
Converts <, >, &, ', " to their corresponding entity codes. Value is true by default. |
The <hs:code/> tag displays the current HTTP status code, if any. A shorthand for:
<%= pageContext.getErrorData().getStatusCode() %>The <hs:message/> tag displays the current error message, if any. A shorthand for:
<%= request.getAttribute("javax.servlet.error.message") %>Optional attributes are:
| Attribute | Description |
|---|---|
default |
The fallback value to output, if no error message is available. |
escapeXml |
Converts <, >, &, ', " to their corresponding entity codes. Value is true by default. |
The <hs:reason/> tag displays the reason for an HTTP status code, if any. Optional attributes are:
| Attribute | Description |
|---|---|
default |
The fallback value to output, if no reason is available. |
code |
The HTTP status error code. If not specified the current status code is used. |
escapeXml |
Converts <, >, &, ', " to their corresponding entity codes. Value is true by default. |
The StatusCode bean can be used to check the class of the status code error. For example, using the JSTL:
<%@ taglib prefix="hs" uri="http://erik.thauvin.net/taglibs/httpstatus" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<jsp:useBean id="statusCode" class="net.thauvin.erik.httpstatus.StatusCode"/>
<c:set target="${statusCode}" property="code"><hs:code/></c:set>
<c:choose>
<c:when test="${statusCode.isClientError()}">
An error occurred on your side. (<hs:reason/>)
</c:when>
<c:otherwise>
An error occurred on our side. (<hs:message/>)
</c:otherwise>
</c:choose>or in a Servlet:
import net.thauvin.erik.httpstatus.StatusCode;
public class ExampleServlet extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response) {
var statusCode = new StatusCode(
(Integer) request.getAttribute("javax.servlet.error.status_code"));
if (statusCode.isError()) {
if (statusCode.isServerError()) {
var reason = statusCode.getReason();
} else {
// ...
}
}
}
}The StatusCode bean methods are:
| Method | Description |
|---|---|
getReason |
Returns the reason for the status code (eg: Internal Server Error) |
isClientError |
Checks if the status code is a client error. |
isError |
Checks if the status code is a server or client error. |
isInfo |
Checks if the status code is informational. |
isRedirect |
Checks if the status code is a redirect. |
isServerError |
Checks if the status code is a server error. |
isSuccess |
Checks if the status code is a success. (OK) |
isValid |
Checks if the status code is valid. |
The reasons are defined in a ResourceBundle properties as follows:
| Status Code | Reason |
|---|---|
100 |
Continue |
101 |
Switching Protocols |
102 |
Processing |
103 |
Early Hints |
110 |
Response is Stale |
111 |
Revalidation Failed |
112 |
Disconnected Operation |
113 |
Heuristic Expiration |
199 |
Miscellaneous Warning |
200 |
OK |
201 |
Created |
202 |
Accepted |
203 |
Non-Authoritative Information |
204 |
No Content |
205 |
Reset Content |
206 |
Partial Content |
207 |
Multi-Status |
208 |
Already Reported |
214 |
Transformation Applied |
218 |
This is fine |
226 |
IM Used |
299 |
Miscellaneous Persistent Warning |
300 |
Multiple Choices |
301 |
Moved Permanently |
302 |
Found/Moved Temporarily |
303 |
See Other |
304 |
Not Modified |
305 |
Use Proxy |
306 |
Unused |
307 |
Temporary Redirect |
308 |
Permanent Redirect |
400 |
Bad Request |
401 |
Unauthorized |
402 |
Payment Required |
403 |
Forbidden |
404 |
Not Found |
405 |
Method Not Allowed |
406 |
Not Acceptable |
407 |
Proxy Authentication Required |
408 |
Request Timeout |
409 |
Conflict |
410 |
Gone |
411 |
Length Required |
412 |
Precondition Failed |
413 |
Payload Too Large |
414 |
URI Too Long |
415 |
Unsupported Media Type |
416 |
Range Not Satisfiable |
417 |
Expectation Failed |
418 |
I'm A Teapot |
419 |
Insufficient Space on Resource |
420 |
Method Failure |
421 |
Misdirected Request |
422 |
Unprocessable Content |
423 |
Locked |
424 |
Failed Dependency |
425 |
Too Early |
426 |
Upgrade Required |
428 |
Precondition Required |
429 |
Too Many Requests |
430 |
Request Header Fields Too Large |
431 |
Request Header Fields Too Large |
440 |
Login Timeout |
444 |
No Response |
449 |
Retry With |
450 |
Blocked by Windows Parental Controls |
451 |
Unavailable For Legal Reasons |
460 |
Client Closed Connection Before Load Balancer Idle Timeout |
463 |
X-Forwarded-For Header with More than 30 IP Addresses |
494 |
Request Header Too Large |
495 |
SSL Certificate Error |
496 |
SSL Certificate Required |
497 |
HTTP Request Sent to HTTPS Port |
498 |
Token Expired/Invalid |
499 |
Client Closed Request |
500 |
Internal Server Error |
501 |
Not Implemented |
502 |
Bad Gateway |
503 |
Service Unavailable |
504 |
Gateway Timeout |
505 |
HTTP Version Not Supported |
506 |
Variant Also Negotiates |
507 |
Insufficient Storage |
508 |
Loop Detected |
509 |
Bandwidth Limit Exceeded |
510 |
Not Extended |
511 |
Network Authentication Required |
520 |
Unknown Error |
521 |
Web Server Is Down |
522 |
Connection Timed Out |
523 |
Origin Is Unreachable |
524 |
A Timeout Occurred |
525 |
SSL Handshake Failed |
526 |
Invalid SSL Certificate |
527 |
Railgun Error |
529 |
Site is overloaded |
530 |
Site is frozen |
540 |
Temporarily Disabled |
561 |
Unauthorized |
598 |
Network Read Timeout Error |
599 |
Network Connect Timeout Error |
783 |
Unexpected Token |
You can query the reason phrase for status codes as follows:
$ java -jar httpstatus-1.1.1.jar 404 500
404: Not Found
500: Internal Server ErrorIf no status code is specified, all will be printed:
$ java -jar httpstatus-1.1.1.jar
100: Continue
101: Switching Protocols
102: Processing
103: Early Hints
110: Response is Stale
111: Revalidation Failed
112: Disconnected Operation
113: Heuristic Expiration
199: Miscellaneous Warning
200: OK
201: Created
202: Accepted
203: Non-Authoritative Information
...You can also print status codes by response classes:
$ java -jar httpstatus-1.1.1.jar 2xx
200: OK
201: Created
202: Accepted
203: Non-Authoritative Information
...If you want to contribute to this project, all you have to do is clone the GitHub repository:
git clone git@github.com:ethauvin/HttpStatus.gitThen use bld to build:
cd HttpStatus
./bld compileThe project has an IntelliJ IDEA project structure. You can just open it after all the dependencies were downloaded and peruse the code.