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1 package ro.infoiasi.donald.compiler.parser;
2
3 import ro.infoiasi.donald.compiler.cfg.*;
4 import java.io.*;
5 import java.util.*;
6 import java.lang.reflect.Constructor  ;
7 import java.lang.reflect.InvocationTargetException ;
8
9 public abstract class AbstractParser implements Parser {
10 protected ParserSpec spec;
11 protected CFG g;
12 protected NonTerminals v;
13 protected Terminals t;
14 protected NonTerminal s;
15 protected Productions p;
16 protected Production sp;
17
18 protected Lexer lexer;
19
20 protected boolean DEBUG = false;
21
22 public AbstractParser(ParserSpec spec, boolean addStartProduction) {
23 this.spec = spec;
24 g = spec.getGrammar();
25 if (addStartProduction) {
26 sp = g.addStartProduction();
27 }
28 v = g.getNonTerminals();
29 t = g.getTerminals();
30 s = g.getStartSymbol();
31 p = g.getProductions();
32 }
33
34 public AbstractParser(ParserSpec spec) {
35 this(spec, false);
36 }
37
38 public AbstractParser(String parserSpecPath, boolean addStartProduction)
39 throws IOException, SpecParseException {
40 this(ParserSpec.load(parserSpecPath), addStartProduction);
41 }
42
43 public AbstractParser(String parserSpecPath)
44 throws IOException, SpecParseException {
45 this(ParserSpec.load(parserSpecPath), false);
46 }
47
48 public CFG getGrammar() {
49 return g;
50 }
51
52 public Lexer getLexer() {
53 return lexer;
54 }
55
56 public void setLexer(String className, String fileName)
57 throws ClassNotFoundException ,
58 FileNotFoundException,
59 ClassCastException ,
60 NoSuchMethodException ,
61 InstantiationException ,
62 IllegalAccessException {
63 setLexer(Class.forName(className), fileName);
64 }
65
66 public void setLexer(Class lexerClass, String fileName)
67 throws ClassNotFoundException ,
68 FileNotFoundException,
69 ClassCastException ,
70 NoSuchMethodException ,
71 InstantiationException ,
72 IllegalAccessException {
73 FileReader fileReader = new FileReader(fileName);
74 if (lexerClass.isInterface()) {
75 throw new ClassCastException (lexerClass+" is an interface");
76 }
77 if (!Lexer.class.isAssignableFrom(lexerClass)) {
78 throw new ClassCastException (lexerClass+" does not implement the Lexer interface");
79 }
80 try {
81 Constructor ctor = lexerClass.getConstructor(new Class [] {Reader.class});
82 lexer = (Lexer)ctor.newInstance(new Object [] {fileReader});
83 } catch (InvocationTargetException e) {
84 throw new RuntimeException (e.getCause());
86 }
87 lexer.setTerminals(t);
88 }
89
90 abstract public void precompute();
91 abstract public List parse() throws IOException, SyntaxError;
92 }
93 |
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