java编写的c语言词法分析器

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1、这是java编写的C语言词法分析器，我将核心代码整理起来，准备放在QQ空间和博客上，目的是互相学习借鉴，希望可以得到高手改进。这个词法分析器实现的功能有打开文件、保存文件、打开帮助文档、文本域内容的剪切和复制和黏贴、进行词法分析程序的项目结构如图，Word类和Unidentifiable类是两个JavaBean类，存放的参数有两个row(整型)、word(String)，row用于获取行数，word用于获取标识符，LexerFrame是词法分析器的界面类，Analyze封装了进行词法分析的核心代码，doc文件夹放一个帮助文档，当用户点击帮助按钮时可以弹出

2、来以帮助用户使用。//核心程序：packagecom.lexer;importjava.util.ArrayList;/***1~20号为关键字,用下标表示,i+1就是其机器码;21~40号为操作符,用下标表示,i+21就是其机器码;41~60号为分界符,* 用下标表示,i+41就是其机器码;用户自定义的标识符，其机器码为51;常数的机器码为52；不可以识别的标识符，其机器码为0*/ publicclassAnalyze{ //关键字 privateStringkeyword[]={"int","long","char","if","else","for

3、","while","return","break","continue",   "switch","case","default","float","double","void","struct","static","do","short"};  //运算符 privateStringoperator[]={"+","-","*","/","%","=",">","<","!","==","!=",">=","<=","++","--","&","&&","

4、

5、","[","]"};  //分界符 privateStringdelimiter[]={"

6、,",";","(",")","{","}","'",""",":","#"};  publicAnalyze(){   }  /** *判断是否是数字 */ publicbooleanisDigit(charch){  if(ch>='0'&&ch<='9'){   returntrue;  }else{   returnfalse;  } }  /** *判断是否是字母的函数 */ publicbooleanisLetter(charch){  if((ch>='a'&&ch<='z')

7、

8、(ch>='A'&&ch<='Z')){   retur

9、ntrue;  }else{   returnfalse;  } }  /** *判断是否由两个运算符组成 */ publicbooleanisTwoOperator(Stringstr,charch){  charlc;  intflag=0;  if(str.length()>1

10、

11、str.length()==0){//字符数大于2和无字符的情况   returnfalse;  }else{//字符数等于2的情况   lc=str.charAt(str.length()-1);   if(ch=='='&&(lc=='>'

12、

13、lc=='<'

14、

15、lc=

16、='='

17、

18、lc=='!')){       }elseif(ch=='+'&&lc=='+'){       }elseif(ch=='-'&&lc=='-'){       }elseif(ch=='

19、'&&lc=='

20、'){       }elseif(ch=='&'&&lc=='&'){       }else{    returnfalse;//否就返回false   }   returntrue;//其它符号的情况都返回true  } }  /** *获取关键字的机器码 */ publicintgetKeywordOpcodes(String

21、str){    inti;   for(i=0;i

22、ator[i]))    break;  }    if(i