pineapple-java/src/main/java/com/fun/Parser.java at main · LionCoder4ever/pineapple-java · GitHub

History

116 lines (103 loc) · 3.87 KB

Raw

100

101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

116

package com.fun;

import lombok.extern.slf4j.Slf4j;

import java.util.ArrayList;

import java.util.List;

import java.util.Objects;

@Slf4j

public class Parser {

private Print parsePrint(Lexer lexer) {

Print p = new Print();

p.setLineNum(lexer.getLineNum());

lexer.nextTokenIs(TokenEnum.TOKEN_PRINT);

lexer.nextTokenIs(TokenEnum.TOKEN_LEFT_PAREN);

lexer.lookAheadAndSkip(TokenEnum.TOKEN_IGNORED);

p.setVariable(this.parseVariable(lexer));

lexer.lookAheadAndSkip(TokenEnum.TOKEN_IGNORED);

lexer.nextTokenIs(TokenEnum.TOKEN_RIGHT_PAREN);

lexer.lookAheadAndSkip(TokenEnum.TOKEN_IGNORED);

return p;

}

private String parseName(Lexer lexer) {

MatchedToken m = lexer.nextTokenIs(TokenEnum.TOKEN_NAME);

return m.getToken();

}

private Statement parseAssignment(Lexer lexer) {

Assignment assignment = new Assignment();

assignment.setLineNum(lexer.getLineNum());

assignment.setVariable(parseVariable(lexer));

lexer.lookAheadAndSkip(TokenEnum.TOKEN_IGNORED);

lexer.nextTokenIs(TokenEnum.TOKEN_EQUAL);

lexer.lookAheadAndSkip(TokenEnum.TOKEN_IGNORED);

assignment.setValue(parseString(lexer));

lexer.lookAheadAndSkip(TokenEnum.TOKEN_IGNORED);

return assignment;

}

private String parseString(Lexer lexer) {

String str = "";

switch (lexer.lookAhead()) {

case TOKEN_DUOQUOTE:

lexer.nextTokenIs(TokenEnum.TOKEN_DUOQUOTE);

lexer.lookAheadAndSkip(TokenEnum.TOKEN_IGNORED);

return str;

case TOKEN_QUOTE:

lexer.nextTokenIs(TokenEnum.TOKEN_QUOTE);

str = lexer.scanBeforeToken(lexer.getTokenNameMap().get(TokenEnum.TOKEN_QUOTE));

lexer.nextTokenIs(TokenEnum.TOKEN_QUOTE);

lexer.lookAheadAndSkip(TokenEnum.TOKEN_IGNORED);

return str;

default:

log.error("parse String error");

System.exit(-1);

return "";

}

private boolean isSourceCodeEnd(TokenEnum tokenEnum) {

return Objects.equals(tokenEnum,TokenEnum.TOKEN_EOF);

}

private Variable parseVariable(Lexer lexer) {

Variable variable = new Variable();

variable.setLineNum(lexer.getLineNum());

lexer.nextTokenIs(TokenEnum.TOKEN_VAR_PREFIX);

String name = parseName(lexer);

variable.setName(name);

lexer.lookAheadAndSkip(TokenEnum.TOKEN_IGNORED);

return variable;

}

private Statement parseStatement(Lexer lexer) {

lexer.lookAheadAndSkip(TokenEnum.TOKEN_IGNORED);

switch (lexer.lookAhead()) {

case TOKEN_PRINT:

return parsePrint(lexer);

case TOKEN_VAR_PREFIX:

return parseAssignment(lexer);

default:

log.error("unknown statement");

System.exit(-1);

return null;

}

public SourceCode parse(String code) {

Lexer lexer = new Lexer(code);

SourceCode sourceCode = parseSourceCode(lexer);

lexer.nextTokenIs(TokenEnum.TOKEN_EOF);

return sourceCode;

}

private List<Statement> parseStatements(Lexer lexer) {

List<Statement> statements = new ArrayList<>();

while (!isSourceCodeEnd(lexer.lookAhead())) {

Statement statement = parseStatement(lexer);

if (Objects.isNull(statement)) {

log.error("parse error");

System.exit(-1);

}

statements.add(statement);

}

return statements;

}

private SourceCode parseSourceCode(Lexer lexer) {

SourceCode sourceCode = new SourceCode();

sourceCode.setLineNum(lexer.getLineNum());

sourceCode.setStatements(parseStatements(lexer));

return sourceCode;

}

pineapple-java/src/main/java/com/fun/Parser.java at main · LionCoder4ever/pineapple-java · GitHub

Expand file tree

Breadcrumbs

Parser.java

Latest commit

History

Breadcrumbs

Parser.java

File metadata and controls