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1
2 package org.python.util;
3
4 import java.io.*;
5 import java.util.*;
6 import javax.servlet.*;
7 import javax.servlet.http.*;
8 import org.python.core.*;
9
10
11
61
62 public class PyServlet extends HttpServlet {
63 private PythonInterpreter interp;
64 private Hashtable cache = new Hashtable();
65 private String  rootPath;
66
67
68 public void init() {
69 rootPath = getServletContext().getRealPath("/");
70 if (!rootPath.endsWith(File.separator))
71 rootPath += File.separator;
72
73 Properties props = new Properties();
74
75 ServletContext context = getServletContext();
77 Enumeration e = context.getInitParameterNames();
78 while (e.hasMoreElements()) {
79 String name = (String ) e.nextElement();
80 props.put(name, context.getInitParameter(name));
81 }
82
83 e = getInitParameterNames();
85 while (e.hasMoreElements()) {
86 String name = (String ) e.nextElement();
87 props.put(name, getInitParameter(name));
88 }
89
90 if (props.getProperty("python.home") == null &&
91 System.getProperty("python.home") == null) {
92 props.put("python.home", rootPath + "WEB-INF" +
93 File.separator + "lib");
94 }
95
96 PythonInterpreter.initialize(System.getProperties(), props,
97 new String [0]);
98 reset();
99
100 PySystemState sys = Py.getSystemState();
101 sys.add_package("javax.servlet");
102 sys.add_package("javax.servlet.http");
103 sys.add_package("javax.servlet.jsp");
104 sys.add_package("javax.servlet.jsp.tagext");
105
106 sys.add_classdir(rootPath + "WEB-INF" +
107 File.separator + "classes");
108
109 sys.add_extdir(rootPath + "WEB-INF" + File.separator + "lib", true);
110 }
111
112
119 public void service(ServletRequest req, ServletResponse res)
120 throws ServletException, IOException
121 {
122 req.setAttribute("pyservlet", this);
123
124 String spath = (String )req.getAttribute(
125 "javax.servlet.include.servlet_path");
126 if (spath == null) {
127 spath = ((HttpServletRequest) req).getServletPath();
128 if (spath == null || spath.length() == 0) {
129 spath = ((HttpServletRequest) req).getPathInfo();
132 }
133 }
134 String rpath = getServletContext().getRealPath(spath);
135
136 interp.set("__file__", rpath);
137
138 HttpServlet servlet = getServlet(rpath);
139 if (servlet != null)
140 servlet.service(req, res);
141 else
142 throw new ServletException("No python servlet found at:" + spath);
143 }
144
145 public void reset() {
146 destroyCache();
147 interp = new PythonInterpreter(null, new PySystemState());
148 cache.clear();
149 PySystemState sys = Py.getSystemState();
150 sys.path.append(new PyString(rootPath));
151
152 String modulesDir = rootPath + "WEB-INF" +
153 File.separator + "jython";
154 sys.path.append(new PyString(modulesDir));
155 }
156
157 private synchronized HttpServlet getServlet(String path)
158 throws ServletException, IOException
159 {
160 CacheEntry entry = (CacheEntry) cache.get(path);
161 if (entry == null)
162 return loadServlet(path);
163 File file = new File(path);
164 if (file.lastModified() > entry.date)
165 return loadServlet(path);
166 return entry.servlet;
167 }
168
169 private HttpServlet loadServlet(String path)
170 throws ServletException, IOException
171 {
172 HttpServlet servlet = null;
173 File file = new File(path);
174
175 int start = path.lastIndexOf(File.separator);
177 if (start < 0)
178 start = 0;
179 else
180 start++;
181 int end = path.lastIndexOf('.');
182 if ((end < 0) || (end <= start))
183 end = path.length();
184 String name = path.substring(start, end);
185
186 try {
187 interp.execfile(path);
188 PyObject cls = interp.get(name);
189 if (cls == null)
190 throw new ServletException("No callable (class or function) "+
191 "named " + name + " in " + path);
192
193 PyObject pyServlet = cls.__call__();
194 Object o = pyServlet.__tojava__(HttpServlet.class);
195 if (o == Py.NoConversion)
196 throw new ServletException("The value from " + name +
197 "must extend HttpServlet");
198 servlet = (HttpServlet)o;
199 servlet.init(getServletConfig());
200
201 } catch (PyException e) {
202 throw new ServletException("Could not create "+
203 "Jython servlet" + e.toString());
204 }
205 CacheEntry entry = new CacheEntry(servlet, file.lastModified());
206 cache.put(path, entry);
207 return servlet;
208 }
209
210 public void destroy() {
211 destroyCache();
212 }
213
214 private void destroyCache() {
215 for (Enumeration e = cache.elements(); e.hasMoreElements(); ) {
216 CacheEntry entry = (CacheEntry) e.nextElement();
217 entry.servlet.destroy();
218 }
219 }
220
221 }
222
223 class CacheEntry {
224 public long date;
225 public HttpServlet servlet;
226
227 CacheEntry(HttpServlet servlet, long date) {
228 this.servlet= servlet;
229 this.date = date;
230 }
231 }
232 |
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