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1 package ro.infoiasi.donald.compiler.cfg;
2
3 import java.util.*;
4
5 public class NonTerminals {
6 private Map varByName = new HashMap();
7 private List varByIndex = new ArrayList();
8
9 public NonTerminal addNew(String  name, String type) {
10 NonTerminal var = new NonTerminal(name, count(), type);
11 if (varByName.containsKey(name)) {
12 throw new RuntimeException ("Duplicate Non-Terminal ("+name+")");
13 }
14 varByName.put(name, var);
15 varByIndex.add(var);
16 return var;
17 }
18
19 public NonTerminal addNew(String name) {
20 return addNew(name, null);
21 }
22
23 public int count() {
24 return varByIndex.size();
25 }
26
27 public Iterator iterator() {
28 return Collections.unmodifiableList(varByIndex).iterator();
29 }
30
31 public NonTerminal find(String name) {
32 return (NonTerminal)varByName.get(name);
33 }
34
35 public NonTerminal find(int index) {
36 if (index < 0 || index >= count()) {
37 return null;
38 } else {
39 return (NonTerminal)varByIndex.get(index);
40 }
41 }
42
43 public void clear() {
44 varByName.clear();
45 varByIndex.clear();
46 }
47
48
49 void removeUseless(List s) {
50 Iterator it = s.iterator();
51 while (it.hasNext()) {
52 NonTerminal a = (NonTerminal)it.next();
53 varByName.remove(a.getName());
54 }
55
56 List tmp = new ArrayList();
57 for (int i = 0; i<varByIndex.size(); i++) {
58 NonTerminal a = (NonTerminal)varByIndex.get(i);
59 if (!s.contains(a)) {
60 a.setIndex(tmp.size());
61 tmp.add(a);
62 }
63 }
64 varByIndex = tmp;
65 }
66
67 public String toString() {
68 StringBuffer sb = new StringBuffer ();
69 Iterator it = iterator();
70 while (it.hasNext()) {
71 sb.append(it.next());
72 if (it.hasNext()) {
73 sb.append(", ");
74 }
75 }
76 return sb.toString();
77 }
78 }
79 |
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