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1 package org.sapia.soto.state.xml;
2
3 import org.apache.commons.lang.ClassUtils;
4 import org.sapia.soto.Env;
5 import org.sapia.soto.EnvAware;
6 import org.sapia.soto.config.ThreadState;
7 import org.sapia.soto.state.Result;
8 import org.sapia.soto.state.Step;
9 import org.sapia.soto.util.Resource;
10 import org.sapia.soto.util.ResourceHandler;
11 import org.sapia.soto.util.Utils;
12
13 import org.sapia.util.text.TemplateContextIF;
14
15 import java.io.IOException  ;
16 import java.io.InputStream ;
17
18 import java.util.Iterator ;
19 import java.util.Map ;
20
21 import javax.xml.transform.Templates ;
22 import javax.xml.transform.TransformerConfigurationException ;
23 import javax.xml.transform.TransformerFactory ;
24 import javax.xml.transform.sax.SAXTransformerFactory ;
25 import javax.xml.transform.sax.TransformerHandler ;
26 import javax.xml.transform.stream.StreamSource ;
27
28
29
44 public class StyleStep implements EnvAware, Step {
45 private Templates _templ;
46 private SAXTransformerFactory _fac;
47 private Resource _file;
48 private Env _env;
49 private long _lastModified = System.currentTimeMillis();
50
51 public StyleStep() throws TransformerConfigurationException {
52 _fac = (SAXTransformerFactory ) TransformerFactory.newInstance();
53 }
54
55 protected StyleStep(SAXTransformerFactory fac) {
56 _fac = fac;
57 }
58
59
62 public String getName() {
63 return ClassUtils.getShortClassName(getClass());
64 }
65
66
71 public void setSrc(String uri)
72 throws IOException , TransformerConfigurationException {
73 ResourceHandler handler = (ResourceHandler) _env.getResourceHandlerFor(uri);
74 _file = handler.getResourceObject(uri);
75 _templ = _fac.newTemplates(new StreamSource (process(
76 _file.getInputStream(), uri)));
77 }
78
79
80
83 public void execute(Result res) {
84 XMLContext ctx;
85 try{
86 ctx = (XMLContext)res.getContext();
87 }catch(ClassCastException e){
88 throw new IllegalStateException ("Expected context to be instance of " + XMLContext.class.getName() + "; got: " + res.getContext().getClass().getName());
89 }
90
91 Map params = ctx.getViewParams();
92
93 if ((_file != null) && (_file.lastModified() != _lastModified)) {
94 try{
95 reload();
96 }catch(Exception e){
97 res.error("Problem reloading stylesheet", e);
98 return;
99 }
100 }
101
102 TransformerHandler handler;
103 try{
104 handler = _fac.newTransformerHandler(_templ);
105 }catch(TransformerConfigurationException e){
106 res.error("Problem creating TransformerHandler", e);
107 return;
108 }
109 Object key;
110 Object val;
111
112 for (Iterator iter = params.keySet().iterator(); iter.hasNext();) {
113 key = iter.next();
114 val = params.get(key);
115
116 if (val != null) {
117 handler.getTransformer().setParameter(key.toString(), val);
118 }
119 }
120 try{
121 TransformChain chain = (TransformChain)ctx.currentObject();
122 chain.add(handler);
123 }catch(ClassCastException e){
124 throw new IllegalStateException ("Expected object on context stack to be instance of " + TransformChain.class.getName());
125 }
126 }
127
128
131 public void setEnv(Env env) {
132 _env = env;
133 }
134
135 private synchronized void reload()
136 throws TransformerConfigurationException , IOException {
137 if (_file.lastModified() != _lastModified) {
138 _templ = _fac.newTemplates(new StreamSource (_file.getInputStream(),
139 _file.getURI()));
140 }
141
142 _lastModified = _file.lastModified();
143 }
144
145 private InputStream process(InputStream is, String uri)
146 throws IOException {
147 TemplateContextIF ctx = ThreadState.currentTemplateContext();
148
149 return Utils.replaceVars(ctx, is, uri);
150 }
151
152 public static class Export {
153 private String _name;
154
155 public void setName(String name) {
156 _name = name;
157 }
158 }
159 }
160 |
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