scanner.java

用java语言做的L语言编译器

package scanner;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.Iterator;

import javax.swing.JOptionPane;

import structureWord.Keywords;
import structureWord.KeywordsStruct;
import structureWord.Symbols;
import structureWord.Token;

import llanguage.BuildWindow;

public class Scanner {

	String name = new String(); // 标识符名字

	int radix; // 数字的进制

	public void startScanner() {
		BuildWindow bw = BuildWindow.getBuildWindow();

		Keywords keyWords = new Keywords();
		Symbols symbols = Symbols.getSymbols();
		Token token = Token.getToken();

		try {
			File f = new File(bw.getFilePath() + bw.getFileName());
			FileReader fr = new FileReader(f);
			BufferedReader bfReader = new BufferedReader(fr); // 文件读取器

			String strLine;
			String strWord;
			int lineNum = 0; // 行号
			int wordNum = 0; // 本行单词号

			boolean isKeyword; // 关键字否
			int strId = 0; // 序号
			while (true) {
				strLine = new String();
				strWord = new String();
				char[] charWord; // 字符数组，存储一行字符
				strLine = bfReader.readLine(); // 读取一行
				if (strLine != null) {
					strLine.trim(); // 略去前后空白符
					lineNum++; // 行号
					wordNum = 0; // 本行单词号
				}

				if (strLine == null) {
					JOptionPane.showMessageDialog(null, "This File is End");
					break;
				}

				int bp = 0; // 字符数组的下标

				charWord = strLine.toCharArray();
				while (bp < charWord.length) {
					strWord = "";

					isKeyword = false;

					while (bp < charWord.length
							&& (charWord[bp] == ' ' || charWord[bp] == '\t')) {
						bp++;
					}
					while (bp < charWord.length && charWord[bp] != ' '
							&& charWord[bp] != '\t') {
						strWord = strWord + charWord[bp++];
					}
					if (strWord == "")
						continue;

					wordNum++; // 单词号自增
					strId++; // 序号自增

					for (Iterator it = keyWords.getArrayKeyWords().iterator(); it
							.hasNext();) {// 这个地方调试了一个晚上，花的时间很长，却意识到了Iterator的用法和细节
						KeywordsStruct ks = (KeywordsStruct) it.next();

						if (strWord.equals((ks.getName()))) {// 对比一致
							Token token1 = new Token();// 辛苦
							token1.getTs().setLabel(strId);
							token1.getTs().setName(ks.getName());
							token1.getTs().setType(ks.getType());
							token1.getTs().setCode(ks.getCode());
							token.getTokenStruct().add(token1.getTs());
							isKeyword = true;
							break;
						}
					}

					if (isKeyword == true) {
						continue;
					} else {// 检查是否是标识符或数字
						boolean hasErrorChar = false;// 非法字符
						char[] charW;
						charW = strWord.toCharArray();
						strWord = "";
						for (int i = 0; i < charW.length; i++) {
							if (!('a' <= charW[i] && charW[i] <= 'z'
									|| 'A' <= charW[i] && charW[i] <= 'Z'
									|| '0' <= charW[i] && charW[i] <= '9' || charW[i] == '.')) {
								charW[i] = ' ';
								hasErrorChar = true;
							}
							strWord = strWord + charW[i];
							if (hasErrorChar) {
								bw.gettaInfo().append(
										"There is a illegal char at Line:"
												+ lineNum + " Word:" + wordNum
												+ "\n");
								bw.gettaInfo().append(
										"ErrorNumber: 1  illegal character\n");
								bw.gettaInfo().append(
										"And the compiler has deleted it\n\n");
							}
						}

						strWord = strWord.replace(" ", "");
						// System.out.println(strWord);

						if (strWord == "") {
							wordNum--;
							strId--;
							continue;
						}// 非法字符结束
						char[] charWo;
						boolean hasCharInNumber = false;
						charWo = strWord.toCharArray();
						if ('a' <= charWo[0] && charWo[0] <= 'z'
								|| 'A' <= charWo[0] && charWo[0] <= 'Z') {// 标识符，写入符号表
							for (int i = 1; i < charWo.length; i++) {
								if (charWo[i] == '.')
									charWo[i] = '-';
							}
							Symbols symbols1 = new Symbols();// 辛苦
							symbols1.getSb().setLabel(strId);
							symbols1.getSb().setName(strWord);
							symbols1.getSb().setType(2);
							symbols1.getSb().setCode(18);
							symbols.getSymbolStruct().add(symbols1.getSb());
						} else if ('0' <= charWo[0] && charWo[0] <= '9') {// 整数或实数,数字开头
							int pointNum = 0;
							int bp2 = charWo.length - 1; // 异常下标
							for (int i = 0; i < charWo.length; i++) {
								if (charWo[i] == '.') {
									pointNum++;
									if (pointNum == 2) {
										bp2 = i;
										break;
									}
								} else if ('a' <= charWo[i] && charWo[i] <= 'z'
										|| 'A' <= charWo[i] && charWo[i] <= 'Z') {
									hasCharInNumber = true;
									bp2 = i;
									break;
								}

							}
							strWord = "";
							for (int i = 0; i < bp2; i++) {
								strWord = strWord + charWo[i];
							}
							if (pointNum == 0) {// 整数
								Symbols symbols1 = new Symbols();// 辛苦
								symbols1.getSb().setLabel(strId);
								symbols1.getSb().setName(strWord);
								symbols1.getSb().setType(3);
								symbols1.getSb().setCode(19);
								symbols.getSymbolStruct().add(symbols1.getSb());
							} else if (pointNum == 1) {// 实数
								Symbols symbols1 = new Symbols();
								symbols1.getSb().setLabel(strId);
								symbols1.getSb().setName(strWord);
								symbols1.getSb().setType(3);
								symbols1.getSb().setCode(20);
								symbols.getSymbolStruct().add(symbols1.getSb());
							} else {
								Symbols symbols1 = new Symbols();
								symbols1.getSb().setLabel(strId);
								symbols1.getSb().setName(strWord);
								symbols1.getSb().setType(3);
								symbols1.getSb().setCode(20);
								symbols.getSymbolStruct().add(symbols1.getSb());
							}
							if (pointNum >= 2) {
								bw.gettaInfo().append(
										"There is a illegal char at Line:"
												+ lineNum + " Word:" + wordNum
												+ "\n");
								bw
										.gettaInfo()
										.append(
												"ErrorNumber: 2  illegal number--there is more than one radix point\n");
								bw
										.gettaInfo()
										.append(
												"And the compiler has deleted it\n\n");
							} else if (hasCharInNumber) {
								bw.gettaInfo().append(
										"There is a illegal char at Line:"
												+ lineNum + " Word:" + wordNum
												+ "\n");
								bw
										.gettaInfo()
										.append(
												"ErrorNumber: 3  illegal number--has characters in number\n");
								bw
										.gettaInfo()
										.append(
												"And the compiler has deleted it\n\n");
							}
						}
					}
				}
			}
		} catch (FileNotFoundException fnfe) {
			JOptionPane.showMessageDialog(null,
					"This file is not found Exception");
		} catch (IOException e) {
			// TODO Auto-generated catch block
			JOptionPane.showMessageDialog(null, "There is a IOException");
		}
		ShowTokenSymbols show = new ShowTokenSymbols();
		show.showTS();
	}

}