53 lines
1.6 KiB
Java
53 lines
1.6 KiB
Java
package token;
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import static java.lang.Character.isDigit;
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import static util.Characters.*;
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import file.FilePosition;
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public class TokenFactoryImpl implements TokenFactory {
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public Token createToken(String text, FilePosition position) {
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if (text.length() == 0)
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throw new EmptyTokenTextException(position);
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char firstCharacter = text.charAt(0);
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switch (firstCharacter) {
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case LEFT_PARENTHESIS:
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return new LeftParenthesis(text, position);
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case RIGHT_PARENTHESIS:
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return new RightParenthesis(text, position);
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case SINGLE_QUOTE:
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return new QuoteMark(text, position);
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case DOUBLE_QUOTE:
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return new QuotedString(text, position);
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default:
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if (isNumeric(firstCharacter, text)) {
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return new Number(text, position);
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} else if (isLegalIdentifierCharacter(firstCharacter)) {
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return new Identifier(text, position);
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}
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}
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throw new BadCharacterException(text, position);
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}
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private boolean isNumeric(char firstCharacter, String text) {
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return isDigit(firstCharacter) || isPrefixedNumeric(firstCharacter, text);
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}
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private boolean isPrefixedNumeric(char firstCharacter, String text) {
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return isNumberPrefix(firstCharacter) && isNextCharacterDigit(text);
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}
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private boolean isNextCharacterDigit(String text) {
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return (text.length() > 1) && isDigit(text.charAt(1));
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}
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public Token createEofToken(FilePosition position) {
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return new Eof("EOF", position);
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}
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}
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