Hello, JSP World!
Posted on 2月 15th, 2012 by cx20
JSP
JSP（JavaServer Pages）は Java EE 周辺技術の一つで Web サーバーで Java プログラムを動作させる技術である。
JSP は HTML に Java コードを埋め込む形で記述する。実行時に Java Servlet のコードが生成されコンパイルされる。
実行環境としては Java Servlet と同様に Apache Tomcat が用いられることが多い。
JSP の類似技術としては、Java Servlet、PHP、ASP、ASP.NET 等がある。
なお、Java EE 周辺技術のバージョンは以下のような対応になっている。
| J2EE |
Servlet |
JSP |
EL |
JSTL |
JSF |
EJB |
| J2EE 1.2 |
2.2 |
1.1 |
– |
– |
– |
1.1 |
| J2EE 1.3 |
2.3 |
1.2 |
– |
1.0 |
– |
2.0 |
| J2EE 1.4 |
2.4 |
2.0 |
2.0 |
1.1 |
– |
2.1 |
| Java EE 5 |
2.5 |
2.1 |
2.1 |
1.2 |
1.2 |
3.0 |
| Java EE 6 |
3.0 |
2.2 |
2.2 |
1.2 |
2.0 |
3.1 |
ソースコード
<html>
<head>
<title>Hello, World!</title>
</head>
<body>
<p><% out.print( "Hello, JSP World!" ); %></p>
</body>
</html> |
<html>
<head>
<title>Hello, World!</title>
</head>
<body>
<p><% out.print( "Hello, JSP World!" ); %></p>
</body>
</html>
上記 JSP コードは、以下の Java Servlet コードと同様である。実際には実行時に Java クラスファイルにコンパイルされ実行される。
ソースコード（Java）
package org.apache.jsp.jsp;
import javax.servlet.*;
import javax.servlet.http.*;
import javax.servlet.jsp.*;
public final class hello_jsp extends org.apache.jasper.runtime.HttpJspBase
implements org.apache.jasper.runtime.JspSourceDependent {
private static final javax.servlet.jsp.JspFactory _jspxFactory =
javax.servlet.jsp.JspFactory.getDefaultFactory();
private static java.util.Map<java.lang.String,java.lang.Long> _jspx_dependants;
private javax.el.ExpressionFactory _el_expressionfactory;
private org.apache.tomcat.InstanceManager _jsp_instancemanager;
public java.util.Map<java.lang.String,java.lang.Long> getDependants() {
return _jspx_dependants;
}
public void _jspInit() {
_el_expressionfactory = _jspxFactory.getJspApplicationContext(getServletConfig().getServletContext()).getExpressionFactory();
_jsp_instancemanager = org.apache.jasper.runtime.InstanceManagerFactory.getInstanceManager(getServletConfig());
}
public void _jspDestroy() {
}
public void _jspService(final javax.servlet.http.HttpServletRequest request, final javax.servlet.http.HttpServletResponse response)
throws java.io.IOException, javax.servlet.ServletException {
final javax.servlet.jsp.PageContext pageContext;
javax.servlet.http.HttpSession session = null;
final javax.servlet.ServletContext application;
final javax.servlet.ServletConfig config;
javax.servlet.jsp.JspWriter out = null;
final java.lang.Object page = this;
javax.servlet.jsp.JspWriter _jspx_out = null;
javax.servlet.jsp.PageContext _jspx_page_context = null;
try {
response.setContentType("text/html");
pageContext = _jspxFactory.getPageContext(this, request, response,
null, true, 8192, true);
_jspx_page_context = pageContext;
application = pageContext.getServletContext();
config = pageContext.getServletConfig();
session = pageContext.getSession();
out = pageContext.getOut();
_jspx_out = out;
out.write("<html>rn");
out.write(" <head>rn");
out.write(" <title>Hello, World!</title>rn");
out.write(" </head>rn");
out.write(" <body>rn");
out.write(" <p>");
out.print( "Hello, JSP World!" );
out.write("</p>rn");
out.write(" </body>rn");
out.write("</html> ");
} catch (java.lang.Throwable t) {
if (!(t instanceof javax.servlet.jsp.SkipPageException)){
out = _jspx_out;
if (out != null && out.getBufferSize() != 0)
try { out.clearBuffer(); } catch (java.io.IOException e) {}
if (_jspx_page_context != null) _jspx_page_context.handlePageException(t);
}
} finally {
_jspxFactory.releasePageContext(_jspx_page_context);
}
}
} |
package org.apache.jsp.jsp;
import javax.servlet.*;
import javax.servlet.http.*;
import javax.servlet.jsp.*;
public final class hello_jsp extends org.apache.jasper.runtime.HttpJspBase
implements org.apache.jasper.runtime.JspSourceDependent {
private static final javax.servlet.jsp.JspFactory _jspxFactory =
javax.servlet.jsp.JspFactory.getDefaultFactory();
private static java.util.Map<java.lang.String,java.lang.Long> _jspx_dependants;
private javax.el.ExpressionFactory _el_expressionfactory;
private org.apache.tomcat.InstanceManager _jsp_instancemanager;
public java.util.Map<java.lang.String,java.lang.Long> getDependants() {
return _jspx_dependants;
}
public void _jspInit() {
_el_expressionfactory = _jspxFactory.getJspApplicationContext(getServletConfig().getServletContext()).getExpressionFactory();
_jsp_instancemanager = org.apache.jasper.runtime.InstanceManagerFactory.getInstanceManager(getServletConfig());
}
public void _jspDestroy() {
}
public void _jspService(final javax.servlet.http.HttpServletRequest request, final javax.servlet.http.HttpServletResponse response)
throws java.io.IOException, javax.servlet.ServletException {
final javax.servlet.jsp.PageContext pageContext;
javax.servlet.http.HttpSession session = null;
final javax.servlet.ServletContext application;
final javax.servlet.ServletConfig config;
javax.servlet.jsp.JspWriter out = null;
final java.lang.Object page = this;
javax.servlet.jsp.JspWriter _jspx_out = null;
javax.servlet.jsp.PageContext _jspx_page_context = null;
try {
response.setContentType("text/html");
pageContext = _jspxFactory.getPageContext(this, request, response,
null, true, 8192, true);
_jspx_page_context = pageContext;
application = pageContext.getServletContext();
config = pageContext.getServletConfig();
session = pageContext.getSession();
out = pageContext.getOut();
_jspx_out = out;
out.write("<html>rn");
out.write(" <head>rn");
out.write(" <title>Hello, World!</title>rn");
out.write(" </head>rn");
out.write(" <body>rn");
out.write(" <p>");
out.print( "Hello, JSP World!" );
out.write("</p>rn");
out.write(" </body>rn");
out.write("</html> ");
} catch (java.lang.Throwable t) {
if (!(t instanceof javax.servlet.jsp.SkipPageException)){
out = _jspx_out;
if (out != null && out.getBufferSize() != 0)
try { out.clearBuffer(); } catch (java.io.IOException e) {}
if (_jspx_page_context != null) _jspx_page_context.handlePageException(t);
}
} finally {
_jspxFactory.releasePageContext(_jspx_page_context);
}
}
}
実行方法
1. Tomcat の公開フォルダ に配置
2. ブラウザで表示
http://localhost:8080/hello/hello.jsp |
1. Tomcat の公開フォルダ に配置
2. ブラウザで表示
http://localhost:8080/hello/hello.jsp
実行結果
Tags: JSP
Categories: Java, JSP, Servlet
