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1
16 package web.layout;
17
18 import java.io.File  ;
19 import java.io.IOException ;
20 import java.io.InputStream ;
21 import java.util.ArrayList ;
22 import java.util.List ;
23
24 import javax.servlet.ServletContext ;
25
26 import org.apache.commons.digester.Digester;
27 import org.apache.commons.digester.ExtendedBaseRules;
28 import org.xml.sax.SAXException ;
29
30
34 public class LayoutConfig {
35
36 private List pages;
37 private boolean freezed = false;
38 private static LayoutConfig config;
39 private static File configFile;
40 private static long lastModified;
41
42 private LayoutConfig(){
43 pages = new ArrayList ();
44 }
45
46
52 public static LayoutConfig getConfig(ServletContext context) throws IOException , SAXException {
53 if(config!=null && configFile.lastModified()==lastModified){
54 return config;
55 }
56 config = new LayoutConfig();
57 Digester dig = new Digester();
58 dig.push(config);
59 dig.setValidating(false);
60 dig.setRules(new ExtendedBaseRules());
61 dig.addSetProperties("layout");
62
63 dig.addObjectCreate("layout/pages/page", Page.class);
64 dig.addSetProperties("layout/pages/page");
65 dig.addBeanPropertySetter("layout/pages/page" + "/?");
66 dig.addSetNext("layout/pages/page", "addPage");
67
68 InputStream in = null;
69 if(context != null){
70 in = context.getResourceAsStream("/WEB-INF/layout.xml");
71 configFile = new File (context.getRealPath("/WEB-INF/layout.xml"));
72 }
73 if(in == null){
74 in = LayoutConfig.class.getResourceAsStream("layout.xml");
75 configFile = new File (LayoutConfig.class.getResource("layout.xml").getPath());
76 }
77 try{
78 lastModified = configFile.lastModified();
79 dig.parse(in);
80 config.freezed = true;
81 }finally{
82 if(in!=null)
83 in.close();
84 }
85 return config;
86 }
87
88 public Page getPage(int index) {
89 return (Page)pages.get(index);
90 }
91 public int pageSize() {
92 return pages.size();
93 }
94
95 public void addPage(Page page) throws IllegalAccessException {
96 if(!freezed)
97 pages.add(page);
98 else
99 throw new IllegalAccessException ("LayoutConfig is fozened.");
100 }
101
102 public static void main(String [] args) throws Exception {
103 LayoutConfig config = LayoutConfig.getConfig(null);
104 int pc = config.pageSize();
105 for(int i=0;i<pc;i++){
106 Page p = config.getPage(i);
107 System.out.println("Name:"+p.getName()+",uri:"+p.getUri()+",param:"+p.getParam());
108 }
109 config = LayoutConfig.getConfig(null);
110 pc = config.pageSize();
111 for(int i=0;i<pc;i++){
112 Page p = config.getPage(i);
113 System.out.println("Name:"+p.getName()+",uri:"+p.getUri()+",param:"+p.getParam());
114 }
115 }
116
117 }
118 |
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