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8  * particular file as subject to the "Classpath" exception as provided
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13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14  * version 2 for more details (a copy is included in the LICENSE file that
15  * accompanied this code).
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24  */
25 
26 package sun.tools.jstat;
27 
28 import java.text.*;
29 import sun.jvmstat.monitor.MonitorException;
30 
31 /**
32  * A class implementing the Closure interface which is used to resolve
33  * all the symbols in the expressions contained in ColumnFormat objects.
34  *
35  * @author Brian Doherty
36  * @since 1.5
37  */
38 public class SymbolResolutionClosure implements Closure {
39     private static final boolean debug =
40             Boolean.getBoolean("SymbolResolutionClosure.debug");
41 
42     private ExpressionEvaluator ee;
43 
SymbolResolutionClosure(ExpressionEvaluator ee)44     public SymbolResolutionClosure(ExpressionEvaluator ee) {
45         this.ee = ee;
46     }
47 
visit(Object o, boolean hasNext)48     public void visit(Object o, boolean hasNext) throws MonitorException {
49         if (! (o instanceof ColumnFormat)) {
50             return;
51         }
52 
53         ColumnFormat c = (ColumnFormat)o;
54         Expression e = c.getExpression();
55         String previous = e.toString();
56         e = (Expression)ee.evaluate(e);
57         if (debug) {
58             System.out.print("Expression: " + previous + " resolved to "
59                              + e.toString());
60         }
61         c.setExpression(e);
62     }
63 }
64