有没有帮帮我这个新手
C语言词法分析算法设计与实现编制一个读单词过程，从输入的源程序中，识别出各个具有独立意义的单词，即基本保留字、标识符、常数、运算符、分隔符五大类。
输入：一段C语言程序
输出：每个单词以及每个单词所在行号
比如：输入如下一段C程序
main()
{
int a,b;
}
输出为：
( main, ”line=1”);
( ( , ”line=1“);
( ) , ”line=1”）；
({ , ”line=2” ）;
( int, “line=2”)；
……………用Java语言，或者C语言，推荐用Java语言。完成所要有的C语言词法分析器。
要求：读文件，或者命令行的形式读取C源程序，输出源程序中每个单词以及每个单词所在行号。
要求：开发出图形化界面，读文件，把结果输出到界面上。
package test;
import java.io.*;
public class WordAnalysis {
private String Keyword[]={"if","int","for","while","do","return","break","continue","main","printf","scanf"};
public String filename;
StringBuffer buffer = new StringBuffer();
public WordAnalysis(String filename) {
this.filename=filename;
}
boolean isKeyword(String ch){
for(int i=0;i<Keyword.length;i++)
if(Keyword[i].equals(ch))
return true;
return false;
}
boolean isDigit(char ch){
if(ch>47&&ch<58)
return true;
else
return false;
}
boolean isLeter(char ch){
if((ch>64&&ch<91)||(ch>96&&ch<123))
return true;
else
return false;
}
public void readFile()throws FileNotFoundException{
try{
FileReader fr = new FileReader(this.filename);
BufferedReader br = new BufferedReader(fr);
String temp = null;
while((temp = br.readLine()) != null)
{
buffer.append(temp);
}
}
catch (Exception e) {
System.out.println("文件操作错误：" + e.toString());
}
}
public void Analysis(){
for(int n=1;n<50;n++)
{
int i=0;
char ch;
while(i<buffer.length()){
ch=buffer.charAt(i);
if(isLeter(ch))
{
StringBuffer temp=new StringBuffer() ;
temp.append(ch);
ch=buffer.charAt(++i);
while(isLeter(ch)||isDigit(ch))
{
temp.append(ch);
ch=buffer.charAt(++i);
}
if(isKeyword(temp.toString()))
System.out.println("( line="+n+"，“ "+temp+" ”)");
else
System.out.println("( line="+n+"，“ "+temp+" ”)");
}
else if((ch==';')||(ch==',')||(ch=='(')||(ch==')')||(ch=='{')||(ch=='}')||(ch=='"'))//判断是否为分隔符
{
System.out.println("( line="+n+"，“ "+ch+" ”)");
i++;
}
else if(isDigit(ch))
{
StringBuffer temp=new StringBuffer();
while(isDigit(ch))
{
temp.append(ch);
ch=buffer.charAt(++i);
}
System.out.println("( line="+n+"，“ "+temp+" ”)");
}
else
{
if((ch!=' '))
{
StringBuffer temp=new StringBuffer();
temp.append(ch);
ch=buffer.charAt(++i);
if(ch=='=')
{
temp.append(ch);
i++;
}
System.out.println("( line="+n+"，“ "+temp+" ”)");
}
else
i++;
}
}
}
}
public static void main(String[] args)throws IOException {
// TODO code application logic here
WordAnalysis fr=new WordAnalysis("c://1.txt");
fr.readFile();
fr.Analysis();
}
}
没有错误，但是运行的结果就是不对，看了好多还是不会啊，求指点
[解决办法]
- Java code
import java.io.BufferedReader;import java.io.FileNotFoundException;import java.io.FileReader;import java.io.IOException;import java.util.ArrayList;import java.util.List;public class WordAnalysis { private String Keyword[] = { "if", "int", "for", "while", "do", "return", "break", "continue", "main", "printf", "scanf" }; public String filename;// StringBuffer buffer = new StringBuffer(); List list = new ArrayList() ; //用List来存放每一行代码 public WordAnalysis(String filename) { this.filename = filename; } boolean isKeyword(String ch) { for (int i = 0; i < Keyword.length; i++) if (Keyword[i].equals(ch)) return true; return false; } boolean isDigit(char ch) { if (ch > 47 && ch < 58) return true; else return false; } boolean isLeter(char ch) { if ((ch > 64 && ch < 91) || (ch > 96 && ch < 123)) return true; else return false; } public void readFile() throws FileNotFoundException { try { FileReader fr = new FileReader(this.filename); BufferedReader br = new BufferedReader(fr); String temp = null; while ((temp = br.readLine()) != null) { list.add(temp) ;//把每一行代码放入list中 //buffer.append(temp); //用StringBuffer只是追加连接，当然得不到每一行的啦 ，会把所有的代码都放到一行上 } } catch (Exception e) { System.out.println("文件操作错误：" + e.toString()); } } public void Analysis() { System.out.println("-----analysis begin -----"); String str = "" ; for (int n = 0; n < list.size(); n++) { int i = 0; char ch; str = (String)list.get(n) ; //取出每一行的代码 while (i < str.length()) { ch = str.charAt(i); if (isLeter(ch)) { StringBuffer temp = new StringBuffer(); temp.append(ch); ch = str.charAt(++i); while (isLeter(ch) || isDigit(ch)) { temp.append(ch); ch = str.charAt(++i); } if (isKeyword(temp.toString())) System.out.println("( line=" + (n+1 ) + "，“ " + temp + " ”)"); else System.out.println("( line=" + (n+1 ) + "，“ " + temp + " ”)"); } else if ((ch == ';') || (ch == ',') || (ch == '(') || (ch == ')') || (ch == '{') || (ch == '}') || (ch == '"'))// 判断是否为分隔符 { System.out.println("( line=" + (n+1 ) + "，“ " + ch + " ”)"); i++; } else if (isDigit(ch)) { StringBuffer temp = new StringBuffer(); while (isDigit(ch)) { temp.append(ch); ch = str.charAt(++i); } System.out.println("( line=" + (n+1 ) + "，“ " + temp + " ”)"); } else { if ((ch != ' ')) { StringBuffer temp = new StringBuffer(); temp.append(ch); ch = str.charAt(++i); if (ch == '=') { temp.append(ch); i++; } System.out.println("( line=" + (n+1 ) + "，“ " + temp + " ”)"); } else i++; } } } System.out.println("-----analysis end -----"); } public static void main(String[] args) throws IOException { // TODO code application logic here WordAnalysis fr = new WordAnalysis("c://1.txt"); fr.readFile(); fr.Analysis(); }}