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📄 frame1.java~220~

📁 java实现的对算术表达式进行词法分析和语法分析,实现过程很简练,值得参考哦!
💻 JAVA~220~
字号:
package suanfuyouxian2;

import java.awt.*;
import java.awt.event.*;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JMenuBar;
import javax.swing.JMenu;
import javax.swing.JMenuItem;
import javax.swing.JLabel;
import com.borland.jbcl.layout.XYLayout;
import com.borland.jbcl.layout.*;
import javax.swing.JTextField;
import javax.swing.JButton;
import javax.swing.JTextArea;
import javax.swing.JScrollPane;

public class Frame1 extends JFrame {
    //声明算符优先表===============================================================
      char[][] table = {
      {'>','>','<','<','<','>','<','>'},
      {'>','>','<','<','<','>','<','>'},
      {'>','>','>','>','<','>','<','>'},
      {'>','>','>','>','<','>','<','>'},
      {'<','<','<','<','<','=','<','-'},
      {'>','>','>','>','-','>','-','>'},
      {'>','>','>','>','-','>','-','>'},
      {'<','<','<','<','<','-','<','='}
      };	//优先关系表:八个字符分别是+-*/()i#,其中'-'表示出错
//声明文法
      String[] wenfa = {"E+E","E-E","E*E","E/E","(E)","i"};	//文法右部
//--------------------------------------------------------
      Stack chStack = new Stack(100);//声明符号栈
      public StringTok[] st = new StringTok[100];
    //===============================================================



    JPanel contentPane;
    JMenuBar jMenuBar1 = new JMenuBar();
    JMenu jMenuFile = new JMenu();
    JMenuItem jMenuFileExit = new JMenuItem();
    JMenu jMenuHelp = new JMenu();
    JMenuItem jMenuHelpAbout = new JMenuItem();
    JLabel statusBar = new JLabel();
    XYLayout xYLayout1 = new XYLayout();
    JTextField jTextField1 = new JTextField();
    JButton jButton1 = new JButton();
    JScrollPane jScrollPane1 = new JScrollPane();
    JTextArea jTextArea1 = new JTextArea();
    public Frame1() {
        try {
            setDefaultCloseOperation(EXIT_ON_CLOSE);
            jbInit();
        } catch (Exception exception) {
            exception.printStackTrace();
        }
    }

    /**
     * Component initialization.
     *
     * @throws java.lang.Exception
     */
    //String input = jTextField1.getText();//取到输入的字符串

    private void jbInit() throws Exception {
        contentPane = (JPanel) getContentPane();
        contentPane.setLayout(xYLayout1);
        setSize(new Dimension(500, 500));
        setTitle("Frame Title");
        statusBar.setText(" ");
        jMenuFile.setText("File");
        jMenuFileExit.setText("Exit");
        jMenuFileExit.addActionListener(new Frame1_jMenuFileExit_ActionAdapter(this));
        jMenuHelp.setText("Help");
        jMenuHelpAbout.setText("About");
        jMenuHelpAbout.addActionListener(new
                                         Frame1_jMenuHelpAbout_ActionAdapter(this));
        contentPane.setBackground(SystemColor.controlShadow);
        jButton1.setText("jButton1");
        jButton1.addActionListener(new Frame1_jButton1_actionAdapter(this));
        jScrollPane1.setHorizontalScrollBarPolicy(JScrollPane.
                                                  HORIZONTAL_SCROLLBAR_ALWAYS);
        jScrollPane1.setVerticalScrollBarPolicy(JScrollPane.
                                                VERTICAL_SCROLLBAR_ALWAYS);
        jTextField1.setText("1+2+3#");
        jMenuBar1.add(jMenuFile);
        jMenuFile.add(jMenuFileExit);
        jMenuBar1.add(jMenuHelp);
        jMenuHelp.add(jMenuHelpAbout);
        setJMenuBar(jMenuBar1);
        contentPane.add(statusBar, new XYConstraints(0, 286, 400, -1));
        contentPane.add(jTextField1, new XYConstraints(59, 36, 154, 36));
        contentPane.add(jScrollPane1, new XYConstraints(51, 168, 373, 257));
        contentPane.add(jButton1, new XYConstraints(251, 36, -1, 36));
        jScrollPane1.getViewport().add(jTextArea1);
    }


    /**
     * File | Exit action performed.
     *
     * @param actionEvent ActionEvent
     */
    void jMenuFileExit_actionPerformed(ActionEvent actionEvent) {
        System.exit(0);
    }

    /**
     * Help | About action performed.
     *
     * @param actionEvent ActionEvent
     */
    void jMenuHelpAbout_actionPerformed(ActionEvent actionEvent) {
        Frame1_AboutBox dlg = new Frame1_AboutBox(this);
        Dimension dlgSize = dlg.getPreferredSize();
        Dimension frmSize = getSize();
        Point loc = getLocation();
        dlg.setLocation((frmSize.width - dlgSize.width) / 2 + loc.x,
                        (frmSize.height - dlgSize.height) / 2 + loc.y);
        dlg.setModal(true);
        dlg.pack();
        dlg.setVisible(true);
    }

    public void jButton1_actionPerformed(ActionEvent actionEvent) {
        //StringBuffer chStack = new StringBuffer();
        int sNo=0;
        int sNo1 =0;
        String input = jTextField1.getText();

        StringTok[] token = new StringTok[input.length()];
        //=======将输入的字符串转换为字符========================================================
        for (int i = 0; i < input.length(); i++) {
                char ch = input.charAt(i);
                if (Character.isDigit(ch)) {
                    token[i] = new StringTok(ch,6);
                } else {
                    switch (ch) {
                    case '#': {
                        token[i] = new StringTok('#',7);
                        break;
                    }
                    case '+': {
                        token[i] = new StringTok('+',0);
                        break;
                    }
                    case '-': {
                        token[i] = new StringTok('-',1);
                        break;
                    }
                    case '*': {
                        token[i] = new StringTok('*',2);
                        break;
                    }
                    case '/': {
                        token[i] = new StringTok('/',3);
                        break;
                    }
                    case '(': {
                        token[i] = new StringTok('(',4);
                        break;
                    }
                    case ')': {
                        token[i] = new StringTok(')',5);
                        break;
                    }
                    }
                }
        }

        StringBuffer guiyue = new StringBuffer();//规约串
        StringBuffer in = new StringBuffer();//符号栈中的字符串
        StringBuffer inStack = new StringBuffer(input);//输入串中的字符
        Stack chS = new Stack(input.length()+1);//声明符号栈
        chS.push('#');
        //char cpop = '';
        //测试
        for (int i = 0; i < token.length; i++) {
            System.out.println(token[i].ch +"   "+ token[i].no);
        }
        jTextArea1.append("符号栈\t输入串\t动作\n");
        in.append("#");
        jTextArea1.append(in.toString() +"\t" +input + "\t" + "预备\n");
        //=================开始分析 1+2+3==================================
        for (int i = 0; i < token.length; i++) {
            char a = token[i].ch;//把下一个字符读入a中
            System.out.println("char  " + a);//tes
            System.out.println("zzz"+chS.peek());//test
            if (Character.isUpperCase(chS.peek()))//取符号栈的终结符
              {
                  char cpop = chS.pop();
                  guiyue.append(cpop);
                  System.out.println("111111111"+guiyue.toString());
              }
          else
          {
              //guiyue.append(a);
          }
            for (int n = 0; n < token.length; n++) {
                if(token[n].ch == chS.peek())
                     {sNo = token[n].no;System.out.println(sNo+"\t"+token[i].no);}
            }//找到与符号栈栈顶字符 相匹配的分析表中的位置
            if (table[sNo][token[i].no] == '<' || table[sNo][token[i].no] == '=')//move in
            {
              //  System.out.println("yijin  "+chS.peek());
                //in.append(chS.peek());
                char cin = inStack.charAt(0);
                chS.push(cin);//压栈
                in.append(cin);
                inStack.deleteCharAt(0);
                jTextArea1.append(in.toString()+"\t"+inStack.toString()+
                                  "\t"+"移进"+cin+"\n");
                guiyue = new StringBuffer();
            }
        else if (table[sNo][token[i].no] == '>')//==算法========================
        {
          i--;
          do{
               char c = chS.pop();//取到符号栈的栈顶
               System.out.println("222222222"+c);//test
               char t = chS.peek();
              // System.out.println("33333333333"+t);//
               System.out.println("==========="+t);
               if (Character.isUpperCase(t))//取终结符=== buzhixing =================
                  {
                      System.out.println("afdsfsdfdsfds====");
                      guiyue.append(c);
                      char t1 = chS.pop();
                      guiyue.append(t1);
                      in.deleteCharAt(0);
                      System.out.println("afdsfsdfdsfds===="+guiyue);
                  }
                 else
                 {
                     //c = chS.pop();
                     //in.deleteCharAt(in.length());
                     guiyue.append(c);//规约一个字符
                     //guiyue.append('E');
                 }
               for (int n = 0; n < token.length; n++) {
                   if(token[n].ch == c)
                      { sNo1 = token[n].no;System.out.println(sNo1+"  "+token[i].no);}
               } //找到与符号栈栈顶字符 相匹配的分析表中的位置
           }
           while(table[sNo1][token[i].no] == '<');//*/
           //guiyue.append(chS.pop());
           System.out.println("guiyue "+ guiyue.toString());//test
           //如何进行规约!!!!!!!!!!!!!!!!!
           //in.deleteCharAt));
           if(guiyue.length()==1)
           {
           in.deleteCharAt(in.length()-1);
           in = in.append('E');
           chS.push('E');
       }
       else if(guiyue.length() == 3)//=====================
       {
           System.out.println("test guiyue E+E");
           in = in.delete(in.length()-4,in.length()-1);
           in = in.append('E');
           chS.push('E');
          // guiyue = new StringBuffer();
       }
       else
       {
           System.out.println("没有可规约的串!!!");
       }
           jTextArea1.append(in.toString()+"\t"+inStack.toString()+"\t"+"规约"+guiyue.toString()+"\n");
           guiyue = new StringBuffer();//清空规约串
           //输出规约串guiyue.append()
           //如何进行规约
           //chStack = chStack.delete(j+1,k);
          // chStack.append('E');
       }
       else if(in.toString() == "#E" && token[i].ch == '#')
       {
           System.out.println("success!!!");
           break;
       }
        }
        }

    }



class Frame1_jButton1_actionAdapter implements ActionListener {
    private Frame1 adaptee;
    Frame1_jButton1_actionAdapter(Frame1 adaptee) {
        this.adaptee = adaptee;
    }

    public void actionPerformed(ActionEvent actionEvent) {
        adaptee.jButton1_actionPerformed(actionEvent);
    }
}


class Frame1_jMenuFileExit_ActionAdapter implements ActionListener {
    Frame1 adaptee;

    Frame1_jMenuFileExit_ActionAdapter(Frame1 adaptee) {
        this.adaptee = adaptee;
    }

    public void actionPerformed(ActionEvent actionEvent) {
        adaptee.jMenuFileExit_actionPerformed(actionEvent);
    }
}


class Frame1_jMenuHelpAbout_ActionAdapter implements ActionListener {
    Frame1 adaptee;

    Frame1_jMenuHelpAbout_ActionAdapter(Frame1 adaptee) {
        this.adaptee = adaptee;
    }

    public void actionPerformed(ActionEvent actionEvent) {
        adaptee.jMenuHelpAbout_actionPerformed(actionEvent);
    }
}

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