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1
16 package web.layout;
17
18 import java.io.IOException  ;
19 import java.io.Reader ;
20 import java.util.ArrayList ;
21 import java.util.Collections ;
22 import java.util.Hashtable ;
23 import java.util.List ;
24
25 import javax.servlet.http.HttpServletRequest ;
26 import javax.servlet.http.HttpServletResponse ;
27 import javax.servlet.jsp.JspException ;
28 import javax.servlet.jsp.PageContext ;
29 import javax.servlet.jsp.tagext.BodyTagSupport ;
30
31 import org.xml.sax.SAXException ;
32
33 import dlog4j.util.StringUtils;
34
35
39 public class LayoutTag extends BodyTagSupport {
40
41 protected final static int BUFFER_SIZE = 512;
42 protected final static String ROOT = "{ROOT}";
43
44 public int doStartTag() throws JspException {
45 return EVAL_BODY_BUFFERED;
46 }
47 public int doEndTag() throws JspException {
48 Reader reader = getBodyContent().getReader();
49 char[] buf = new char[BUFFER_SIZE];
50 try{
51 HttpServletRequest req = (HttpServletRequest )pageContext.getRequest();
52 HttpServletResponse res = (HttpServletResponse )pageContext.getResponse();
53 StringBuffer content1 = new StringBuffer (BUFFER_SIZE);
54 do{
55 int rc = reader.read(buf);
56 if(rc>0)
57 content1.append(buf,0,rc);
58 if(rc<BUFFER_SIZE)
59 break;
60 }while(true);
61 String html = StringUtils.replaceIgnoreCase(content1.toString(), ROOT, req.getContextPath());
62 List tokens = listTokens(html);
63 int curIdx = 0;
64 for(int i=0;i<tokens.size();i++){
65 Token token = (Token)tokens.get(i);
66 pageContext.getOut().write(html.substring(curIdx,token.begin));
67 try{
68 if(ROOT.equals(token.name)){
69 pageContext.getOut().write(req.getContextPath());
70 }
71 else{
72 String tokenPage = getTokenPage(token.name,token.page);
73 pageContext.include(tokenPage);
74 }
75 }catch (Exception e0) {
76 pageContext.getServletContext().log("LayoutTag.doEndTag page="+token.page,e0);
77 pageContext.setAttribute("excetion", e0, PageContext.REQUEST_SCOPE);
78 if(!errorPage.startsWith("/"))
79 pageContext.include(baseDir + errorPage);
80 else
81 pageContext.include(errorPage);
82 }
83 curIdx = token.begin + token.name.length();
84 }
85 pageContext.getOut().write(html.substring(curIdx));
86 }catch(Exception e1){
87 pageContext.getServletContext().log("LayoutTag.doEndTag",e1);
88 }
89 return EVAL_PAGE;
90 }
91
92
98 protected String getTokenPage(String token, String page){
99 String sPage;
100 if(mainPage==null || !"$BODY$".equals(token))
101 sPage = page;
102 else
103 sPage = (String )pageContext.findAttribute(mainPage);
104 return (sPage.startsWith("/"))?sPage:(baseDir + sPage);
105 }
106
107
114 protected synchronized List listTokens(String content) throws Exception {
115 int hashcode = content.toString().hashCode();
116 Integer layout_hashcode = (Integer )ht_hashcodes.get(id);
117 final int layout_hc = (layout_hashcode!=null)?layout_hashcode.intValue():-1;
118 final List last_tokens = (List )ht_tokens.get(id);
119 if(hashcode==layout_hc && last_tokens!=null)
120 return last_tokens;
121 List tokens = new ArrayList ();
122 LayoutConfig config = LayoutConfig.getConfig(pageContext.getServletContext());
123 int pc = config.pageSize();
124 for(int i=0;i<pc;i++){
125 Page page = config.getPage(i);
126 int begin = content.indexOf(page.getName());
127 if(begin!=-1){
128 Token token = new Token();
129 token.begin = begin;
130 token.name = page.getName();
131 token.page = page.getUri();
132 tokens.add(token);
133 }
134 }
135 int begin = content.indexOf(ROOT);
136 if(begin!=-1){
137 Token token = new Token();
138 token.begin = begin;
139 token.name = ROOT;
140 tokens.add(token);
141 }
142 Collections.sort(tokens); ht_hashcodes.put(id, new Integer (hashcode));
145 ht_tokens.put(id, tokens);
146 return tokens;
147 }
148
149 private static Hashtable ht_tokens = new Hashtable ();
150 private static Hashtable ht_hashcodes = new Hashtable ();
151
152
155 private class Token implements Comparable {
156 public int ident;
157 public String name;
158 public int begin;
159 public String page;
160
161 public int compareTo(Object obj) {
162 return begin - ((Token)obj).begin;
163 }
164 public int hashCode() {
165 return begin;
166 }
167 };
168
169 protected String mainPage;
170 protected String baseDir = "/WEB-INF/jsp/";
171 protected String errorPage = "error/error.jsp";
172
173 public String getMainPage() {
174 return mainPage;
175 }
176 public void setMainPage(String mainPage) {
177 this.mainPage = mainPage;
178 }
179 public String getBaseDir() {
180 return baseDir;
181 }
182 public void setBaseDir(String baseDir) {
183 if(!baseDir.endsWith("/"))
184 baseDir += "/";
185 this.baseDir = baseDir;
186 }
187 public String getErrorPage() {
188 return errorPage;
189 }
190 public void setErrorPage(String errorPage) {
191 this.errorPage = errorPage;
192 }
193 }
194 |
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