43 lines
861 B
Java
Executable File
43 lines
861 B
Java
Executable File
package frontend.lexer;
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import java.util.ArrayList;
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public class TokenStream {
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private ArrayList<Token> tokens;
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private int currentIndex;
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public TokenStream(ArrayList<Token> tokens) {
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this.tokens = tokens;
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}
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public Token read() {
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if (currentIndex < tokens.size()) {
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return tokens.get(currentIndex++);
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} else {
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return null;
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}
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}
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public void recall() {
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if (currentIndex > 0) {
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currentIndex--;
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}
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}
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public int getCurrentIndex() {
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return currentIndex;
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}
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public void resetIndex(int index) {
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currentIndex = index;
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}
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public Token peek(int step) {
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if (currentIndex + step < tokens.size()) {
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return tokens.get(currentIndex + step);
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} else {
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return null;
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}
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}
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}
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