我重新编辑了一个东西,是页面转移的,由AddServlet.java,BookWriter.java,Book.java,hello.jsp源代码按顺序如下package jp.bcat;import java.io.*;import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.*;import java.text.SimpleDateFormat;
import java.util.Date;/**
* Servlet implementation class AddServlet
*/
@WebServlet("/AddServlet")
public class AddServlet extends HttpServlet {
private static final long serialVersionUID = 1L; /**
* @see HttpServlet#HttpServlet()
*/ protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
String step = request.getParameter("step");
if ("prepare".equals(step))
prepare(request, response); }
void prepare(HttpServletRequest request, HttpServletResponse response) throws IOException {
String errorMessage = "";
Book book = new Book();
String title = request.getParameter("title");
book.setTitle(title);
if (title == null || title.length() == 0)
errorMessage += "<P>タイトルを入力してください。</P>";
response.setContentType("text/html; charset=utf-8");
PrintWriter out = response.getWriter();
out.println("<HTML><HEAD><TITLE>図書登録確認</TITLE></HEAD>");
if (errorMessage.length() == 0) {
out.println("<BODY>"); out.println("<PRE>");
new BookWriter(out, "+ ").write(book);
out.println("</PRE>"); out.println("</BODY>");
}
out.println("</HTML>");
}
}package jp.bcat;import java.io.PrintWriter;public class BookWriter {
protected PrintWriter out;
protected String indent; public BookWriter(PrintWriter out, String indent) {
this.out = out;
this.indent = indent;
} public void write(Book book) {
out.println(indent + "タイトル: " + book.getTitle()); }
}package jp.bcat;import java.io.Serializable;public class Book implements Serializable { protected String title; public String getTitle() {
return title;
} public void setTitle(String value) {
title = value;
}
}<%@ page language="java" contentType="text/html; charset=utf-8"
pageEncoding="windows-31j"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Insert title here</title>
</head>
<body>
<FORM action="AddServlet" method="POST">
<TABLE>
<TR><TD>タイトル: </TD><TD><INPUT name="title"></TD></TR> <TR><TD><INPUT type="submit" value="登録"></TD></TR>
<INPUT type="hidden" name="step" value="prepare">
</TABLE>
</FORM>
</body>
</html>如果输入汉字,显示的是????的乱码。
我估计我好像是Filter的设置好像不对,我的Filter的代码如下,如何在程序中使用这个过滤器呢?请高手们帮助,谢谢大家了。
package jp.bcat.util;import java.io.IOException;
import javax.servlet.*;public class RequestEncodingFilter implements Filter {
private String encoding; public void init(FilterConfig config) throws ServletException {
encoding = config.getInitParameter("encoding");
} public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException {
if (encoding != null)
req.setCharacterEncoding(encoding);
chain.doFilter(req, res);
} public void destroy() {
}
}
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.*;import java.text.SimpleDateFormat;
import java.util.Date;/**
* Servlet implementation class AddServlet
*/
@WebServlet("/AddServlet")
public class AddServlet extends HttpServlet {
private static final long serialVersionUID = 1L; /**
* @see HttpServlet#HttpServlet()
*/ protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
String step = request.getParameter("step");
if ("prepare".equals(step))
prepare(request, response); }
void prepare(HttpServletRequest request, HttpServletResponse response) throws IOException {
String errorMessage = "";
Book book = new Book();
String title = request.getParameter("title");
book.setTitle(title);
if (title == null || title.length() == 0)
errorMessage += "<P>タイトルを入力してください。</P>";
response.setContentType("text/html; charset=utf-8");
PrintWriter out = response.getWriter();
out.println("<HTML><HEAD><TITLE>図書登録確認</TITLE></HEAD>");
if (errorMessage.length() == 0) {
out.println("<BODY>"); out.println("<PRE>");
new BookWriter(out, "+ ").write(book);
out.println("</PRE>"); out.println("</BODY>");
}
out.println("</HTML>");
}
}package jp.bcat;import java.io.PrintWriter;public class BookWriter {
protected PrintWriter out;
protected String indent; public BookWriter(PrintWriter out, String indent) {
this.out = out;
this.indent = indent;
} public void write(Book book) {
out.println(indent + "タイトル: " + book.getTitle()); }
}package jp.bcat;import java.io.Serializable;public class Book implements Serializable { protected String title; public String getTitle() {
return title;
} public void setTitle(String value) {
title = value;
}
}<%@ page language="java" contentType="text/html; charset=utf-8"
pageEncoding="windows-31j"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Insert title here</title>
</head>
<body>
<FORM action="AddServlet" method="POST">
<TABLE>
<TR><TD>タイトル: </TD><TD><INPUT name="title"></TD></TR> <TR><TD><INPUT type="submit" value="登録"></TD></TR>
<INPUT type="hidden" name="step" value="prepare">
</TABLE>
</FORM>
</body>
</html>如果输入汉字,显示的是????的乱码。
我估计我好像是Filter的设置好像不对,我的Filter的代码如下,如何在程序中使用这个过滤器呢?请高手们帮助,谢谢大家了。
package jp.bcat.util;import java.io.IOException;
import javax.servlet.*;public class RequestEncodingFilter implements Filter {
private String encoding; public void init(FilterConfig config) throws ServletException {
encoding = config.getInitParameter("encoding");
} public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException {
if (encoding != null)
req.setCharacterEncoding(encoding);
chain.doFilter(req, res);
} public void destroy() {
}
}
改为 pageEncoding="UTF-8"试试
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.*;import java.text.SimpleDateFormat;
import java.util.Date;/**
* Servlet implementation class AddServlet
*/
@WebServlet("/AddServlet")
public class AddServlet extends HttpServlet {
private static final long serialVersionUID = 1L; /**
* @see HttpServlet#HttpServlet()
*/ protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
String step = request.getParameter("step");
if ("prepare".equals(step))
prepare(request, response); }
void prepare(HttpServletRequest request, HttpServletResponse response) throws IOException {
String errorMessage = "";
Book book = new Book();
String title = request.getParameter("title");
if(title.trim!=null){
String temTitle = new String(title .getBytes("ISO-8859-1"),"GB2312");
book.setTitle(temTitle);
}else{
book.setTitle("");
}
if (title == null || title.length() == 0)
errorMessage += "<P>タイトルを入力してください。</P>";
response.setContentType("text/html; charset=utf-8");
PrintWriter out = response.getWriter();
out.println("<HTML><HEAD><TITLE>図書登録確認</TITLE></HEAD>");
if (errorMessage.length() == 0) {
out.println("<BODY>"); out.println("<PRE>");
new BookWriter(out, "+ ").write(book);
out.println("</PRE>"); out.println("</BODY>");
}
out.println("</HTML>");
}
}new String(iso.getBytes("ISO-8859-1"),"GB2312");
encoding = config.getInitParameter("encoding");web.xml里面是怎么配置的这个参数?
<!DOCTYPE web-app PUBLIC
"-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
"http://java.sun.com/dtd/web-app_2_3.dtd">
<web-app>
<filter>
<filter-name>requestEncodingFilter</filter-name>
<filter-class>jp.bcat.util.RequestEncodingFilter</filter-class>
<init-param>
<param-name>encoding</param-name>
<param-value>Shift_JIS</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>requestEncodingFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<servlet>
<servlet-name>add</servlet-name>
<servlet-class>jp.bcat.AddServlet</servlet-class>
</servlet>
<servlet>
<servlet-name>list</servlet-name>
<servlet-class>jp.bcat.ListServlet</servlet-class>
</servlet>
<servlet>
<servlet-name>delete</servlet-name>
<servlet-class>jp.bcat.DeleteServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>add</servlet-name>
<url-pattern>/add</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>list</servlet-name>
<url-pattern>/list</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>delete</servlet-name>
<url-pattern>/delete</url-pattern>
</servlet-mapping>
</web-app>
<param-name>encoding</param-name>
<param-value>Shift_JIS</param-value>
</init-param>
Shift_JIS改为utf-8试试
<servlet>
<servlet-name>add</servlet-name>
<servlet-class>jp.bcat.AddServlet</servlet-class>
</servlet>
和
<servlet-mapping>
<servlet-name>add</servlet-name>
<url-pattern>/add</url-pattern>
</servlet-mapping>
这两个地方都设成add,就是说如果把<FORM action="AddServlet" method="POST">改成<FORM action="add" method="POST">这个add能够实现AddServlet,但是
但是从http://localhost:8080/char/hello.jsp按登录按钮之后,出现
type ステータスレポートメッセージ /char/add説明 The requested resource (/char/add) is not available.
这个错误,应该是web.xml的设定没有起到作用,如果实现不了,可能这个和filer过滤器也应该起不到作用吧?
请求高手的帮助,十分感谢!!!!!
String step = request.getParameter("step");
在string前加入request.setCharacterEncoding("Windows-31J");
问题得到解决,谢谢大家的帮助。