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UTF-8 encoding in JSP page

由 只愿长相守 提交于 2020-01-08 21:01:29

问题


I have a JSP page whose page encoding is ISO-8859-1. This JSP page there is in a question answer blog. I want to include special characters during Q/A posting.

The problem is JSP is not supporting UTF-8 encoding even I have changed it from ISO-8859-1 to UTF-8. These characters (~,%,&,+) are making problem. When I am posting these character either individually or with the combination of any character it is storinh null in the database and when I remove these characters while posting application it is working fine.

Can any one suggest some solution?


回答1:


You should use the same encoding on all layers of your application to avoid this problem. It is useful to add a filter to set the encoding:

public void doFilter(ServletRequest request,
                     ServletResponse response,
                     FilterChain chain) throws ServletException {
   request.setCharacterEncoding("UTF-8");
   chain.doFilter(request, response);
}

To only set the encoding on your JSP pages, add this line to them:

<%@ page contentType="text/html; charset=UTF-8" %>

Configure your database to use the same char encoding as well.

If you need to convert the encoding of a string see:

  • Encoding conversion in java

I would not recommend to store HTML encoded text in your database. For example, if you need to generate a PDF (or anything other than HTML) you need to convert the HTML encoding first.




回答2:


The full JSP tag should be something like this, mind the pageEncoding too:

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>

Some old browsers mess up with the encoding too. you can use the HTML tag

 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />

Also the file should be recorded in UTF-8 format, if you are using Eclipse left-click on the file->Properties->Check out ->Text file encoding.




回答3:


I also had an issue displaying charectors like "Ṁ Ů".I added the following to my web.xml.

<jsp-config>
    <jsp-property-group>
        <url-pattern>*.jsp</url-pattern>
        <page-encoding>UTF-8</page-encoding>
    </jsp-property-group>
</jsp-config>

This solved the issue in the pages except header. Tried many ways to solve this and nothing worked in my case. The issue with header was header jsp page is included from another jsp. So gave the encoding to the import and that solved my problem. 

<c:import url="/Header1.jsp" charEncoding="UTF-8"/>

Thanks




回答4:


You have to make sure the file is been saved with UTF-8 encoding. You can do it with several plain text editors. With Notepad++, i.e., you can choose in the menu Encoding-->Encode in UTF-8. You can also do it even with Windows' Notepad (Save As --> Encoding UTF-8). If you are using Eclipse, you can set it in the file's Properties.

Also, check if the problem is that you have to escape those characters. It wouldn't be strange that were your problem, as one of the characters is &.




回答5:


This thread can help you: Passing request parameters as UTF-8 encoded strings

Basically:

request.setCharacterEncoding("UTF-8");
String login = request.getParameter("login");
String password = request.getParameter("password");

Or you use javascript on jsp file:

var userInput = $("#myInput").val();            
var encodedUserInput = encodeURIComponent(userInput);
$("#hiddenImput").val(encodedUserInput);

and after recover on class:

String parameter = URLDecoder.decode(request.getParameter("hiddenImput"), "UTF-8");



回答6:


I used encoding filter which has solved my all encoding problem... 

 package com.dina.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;

    /**
     *
     * @author DINANATH
     */
    public class EncodingFilter implements Filter {

        private String encoding = "utf-8";

        public void doFilter(ServletRequest request,ServletResponse response, FilterChain filterChain) throws IOException, ServletException {
            request.setCharacterEncoding(encoding);
    //                response.setContentType("text/html;charset=UTF-8");
                    response.setCharacterEncoding(encoding);
            filterChain.doFilter(request, response);

        }

        public void init(FilterConfig filterConfig) throws ServletException {
            String encodingParam = filterConfig.getInitParameter("encoding");
            if (encodingParam != null) {
                encoding = encodingParam;
            }
        }

        public void destroy() {
            // nothing todo
        }

    }

in web.xml

    <filter>
        <filter-name>EncodingFilter</filter-name>
        <filter-class>
        com.dina.filter.EncodingFilter
        </filter-class>
        <init-param>
            <param-name>encoding</param-name>
            <param-value>UTF-8</param-value>
        </init-param>
        <init-param>
        <param-name>forceEncoding</param-name>
        <param-value>true</param-value>
    </init-param>
    </filter>
    <filter-mapping>
        <filter-name>EncodingFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>



回答7:


This is a common issue.

one of the easiest way to solve is to check if the special character is reaching inside the action layer and then modifying the special character in the java code.

If you are able to view this character in Action or any other java layer of your choice (Like business layer), just replace the character with corresponding HTML character using the StringEscapeUtils.html#escapeHtml

After doing the escape. use the new string to save to the DB.




回答8:


This are special characters in html. Why dont you encode it? Check it out: http://www.degraeve.com/reference/specialcharacters.php




回答9:


This will help you.

<%@page contentType="text/html" pageEncoding="UTF-8"%>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
</head>



回答10:


I had the same problem using special characters as delimiters on JSP. When the special characters got posted to the servlet, they all got messed up. I solved the issue by using the following conversion:

String str = new String (request.getParameter("string").getBytes ("iso-8859-1"), "UTF-8");



回答11:


i add this shell script to convert jsp files from IS

#!/bin/sh

###############################################
## this script file must be placed in the parent  
## folder of the to folders "in" and "out"
## in contain the input jsp files
## out will containt the generated jsp files
## 
###############################################

find in/ -name *.jsp | 
    while read line; do 
        outpath=`echo $line | sed -e 's/in/out/'` ;
        parentdir=`echo $outpath | sed -e 's/[^\/]*\.jsp$//'` ;
        mkdir -p $parentdir
        echo $outpath ;
        iconv -t UTF-8 -f ISO-8859-1 -o $outpath $line ;
    done



回答12:


Thanks for all the Hints. Using Tomcat8 I also added a filter like @Jasper de Vries wrote. But in the newer Tomcats nowadays there is a filter already implemented that can be used resp just uncommented in the Tomcat web.xml:

<filter>
    <filter-name>setCharacterEncodingFilter</filter-name>
    <filter-class>org.apache.catalina.filters.SetCharacterEncodingFilter</filter-class>
    <init-param>
        <param-name>encoding</param-name>
        <param-value>UTF-8</param-value>
    </init-param>
    <async-supported>true</async-supported>
</filter>
...
<filter-mapping>
    <filter-name>setCharacterEncodingFilter</filter-name>
    <url-pattern>/*</url-pattern>
</filter-mapping>

And like all others posted; I added the URIEncoding="UTF-8" to the Tomcat Connector in Apache. That also helped.

Important to say, that Eclipse (if you use this) has a copy of its web.xml and overwrites the Tomcat-Settings as it was explained here: Broken UTF-8 URI Encoding in JSPs




回答13:


Page encoding or anything else do not matter a lot. ISO-8859-1 is a subset of UTF-8, therefore you never have to convert ISO-8859-1 to UTF-8 because ISO-8859-1 is already UTF-8,a subset of UTF-8 but still UTF-8. Plus, all that do not mean a thing if You have a double encoding somewhere. This is my "cure all" recipe for all things encoding and charset related:

        String myString = "heartbroken ð";

//String is double encoded, fix that first.

                myString = new String(myString.getBytes(StandardCharsets.ISO_8859_1), StandardCharsets.UTF_8);
                String cleanedText = StringEscapeUtils.unescapeJava(myString);
                byte[] bytes = cleanedText.getBytes(StandardCharsets.UTF_8);
                String text = new String(bytes, StandardCharsets.UTF_8);
                Charset charset = Charset.forName("UTF-8");
                CharsetDecoder decoder = charset.newDecoder();
                decoder.onMalformedInput(CodingErrorAction.IGNORE);
                decoder.onUnmappableCharacter(CodingErrorAction.IGNORE);
                CharsetEncoder encoder = charset.newEncoder();
                encoder.onMalformedInput(CodingErrorAction.IGNORE);
                encoder.onUnmappableCharacter(CodingErrorAction.IGNORE);
                try {
                    // The new ByteBuffer is ready to be read.
                    ByteBuffer bbuf = encoder.encode(CharBuffer.wrap(text));
                    // The new ByteBuffer is ready to be read.
                    CharBuffer cbuf = decoder.decode(bbuf);
                    String str = cbuf.toString();
                } catch (CharacterCodingException e) {
                    logger.error("Error Message if you want to");

                }



回答14:


The default JSP file encoding is specified by JSR315 as ISO-8859-1. This is the encoding that the JSP engine uses to read the JSP file and it is unrelated to the servlet request or response encoding.

If you have non-latin characters in your JSP files, save the JSP file as UTF-8 with BOM or set pageEncoding in the beginning of the JSP page:

<%@page pageEncoding="UTF-8" %>

However, you might want to change the default to UTF-8 globally for all JSP pages. That can be done via web.xml:

<jsp-config>
    <jsp-property-group>
        <url-pattern>/*</url-pattern>
        <page-encoding>UTF-8</page-encoding>
    </jsp-property-group>
</jsp-config>

Or, when using Spring Boot with an (embedded) Tomcat, via a TomcatContextCustomizer:

@Component
public class JspConfig implements TomcatContextCustomizer {
    @Override
    public void customize(Context context) {
        JspPropertyGroup pg = new JspPropertyGroup();
        pg.addUrlPattern("/*");
        pg.setPageEncoding("UTF-8");
        pg.setTrimWhitespace("true"); // optional, but nice to have
        ArrayList<JspPropertyGroupDescriptor> pgs = new ArrayList<>();
        pgs.add(new JspPropertyGroupDescriptorImpl(pg));
        context.setJspConfigDescriptor(new JspConfigDescriptorImpl(pgs, new ArrayList<TaglibDescriptor>()));
    }
}

For JSP to work with Spring Boot, don't forget to include these dependencies:

    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-tomcat</artifactId>
        <scope>provided</scope>
    </dependency>
    <dependency>
        <groupId>org.apache.tomcat.embed</groupId>
        <artifactId>tomcat-embed-jasper</artifactId>
        <scope>provided</scope>
    </dependency>

And to make a "runnable" .war file, repackage it:

<build>
    <plugins>
        <plugin>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-maven-plugin</artifactId>
            <executions>
                <execution>
                    <phase>package</phase>
                    <goals>
                        <goal>repackage</goal>
                    </goals>
                </execution>
            </executions>
        </plugin>
   . . .


来源：https://stackoverflow.com/questions/12723339/utf-8-encoding-in-jsp-page

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utf-8
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