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25 
26 package sun.tools.jstat;
27 
28 import java.util.*;
29 import java.net.*;
30 import java.io.*;
31 
32 /**
33  * A class for finding a specific special option in the jstat_options file.
34  *
35  * @author Brian Doherty
36  * @since 1.5
37  */
38 public class OptionFinder {
39 
40     private static final boolean debug = false;
41 
42     List<URL> optionsSources;
43 
OptionFinder(List<URL> optionsSources)44     public OptionFinder(List<URL> optionsSources) {
45         this.optionsSources = optionsSources;
46     }
47 
getOptionFormat(String option, boolean useTimestamp)48     public OptionFormat getOptionFormat(String option, boolean useTimestamp) {
49         OptionFormat of = getOptionFormat(option, optionsSources);
50         OptionFormat tof = null;
51         if ((of != null) && (useTimestamp)) {
52             // prepend the timestamp column as first column
53             tof = getOptionFormat("timestamp", optionsSources);
54             if (tof != null) {
55                 ColumnFormat cf = (ColumnFormat)tof.getSubFormat(0);
56                 of.insertSubFormat(0, cf);
57             }
58         }
59         return of;
60     }
61 
getOptionFormat(String option, List<URL> sources)62     protected OptionFormat getOptionFormat(String option, List<URL> sources) {
63         OptionFormat of = null;
64         for (URL u : sources) {
65             try {
66                 Reader r = new BufferedReader(
67                         new InputStreamReader(u.openStream()));
68                 of = new Parser(r).parse(option);
69                 if (of != null)
70                     break;
71             } catch (IOException e) {
72                 if (debug) {
73                     System.err.println("Error processing " + u
74                                        + " : " + e.getMessage());
75                     e.printStackTrace();
76                 }
77             } catch (ParserException e) {
78                 // Exception in parsing the options file.
79                 System.err.println(u + ": " + e.getMessage());
80                 System.err.println("Parsing of " + u + " aborted");
81             }
82         }
83         return of;
84     }
85 }
86