java大作业 KShinglingAlgorithm

wiki上关于KShingling Algorithm（w-shingling）的说明：

http://en.wikipedia.org/wiki/W-shingling

摘要：

In natural language processing a w-shingling is a set of unique "shingles"—contiguous subsequences of tokens in a document—that can be used to gauge the similarity of two documents. The w denotes the number of tokens in each shingle in the set.

The document, "a rose is a rose is a rose" can be tokenized as follows:

(a,rose,is,a,rose,is,a,rose)

The set of all contiguous sequences of 4 tokens (N-grams, here: 4-grams) is

{ (a,rose,is,a), (rose,is,a,rose), (is,a,rose,is), (a,rose,is,a), (rose,is,a,rose) } = { (a,rose,is,a), (rose,is,a,rose), (is,a,rose,is) }

我理解的此算法，是把每段文本都像上述分解后，统计两段文本的合集b，再统计交集a，用a/b得到相似度。

写得有些复杂：

 package bigproject2;

 import javax.swing.JOptionPane;

 public class union {
     //求子集
     public String[] ziji(String str)
     {
         char[] ch=str.toCharArray();
         int c=0;
         for(int i=0;i<ch.length;i++)
         {
             if(ch[i]==' ')
                 c++;
         }
         //建立单词数组
         String[] strt=new String[c+1];
         for(int i=0;i<c+1;i++)
             strt[i]="";
         int h=0;
         for(int i=0;i<c+1;i++)
         {
             for(int j=h;j<ch.length;j++)
             {
                 if(ch[j]==' ')
                 {
                     h=j+1;
                     break;
                 }
                 else strt[i]+=ch[j];
             }
         }
         return strt;
     }
     //按k分，并去掉重复子集。
     public String[] cut(String[] str,int k) throws MyException{
         if(str.length<k)
                 throw new MyException("单词数少于"+k+"，无法进行计算！");
         String[] t=new String[str.length-k+1];
         for(int i=0;i<str.length-k+1;i++)
             t[i]="";
         int h=0,m=0;
         for(;h<str.length-k+1;h++)
         {
             for(int i=m;i<m+k;i++)
                 t[h]+=str[i];
             m++;
         }
         //去掉重复部分
         int merge=0;
         for(int i=0;i<t.length-1;i++)
         {
             if(t[i].equals("")) break;
             for(int j=i+1;j<t.length;j++)
             {
                 if(t[i].equals(t[j]))
                 {
                     merge++;
                     int y=j;
                     for(;y<t.length-1;y++)
                     {
                         t[y]=t[y+1];
                     }
                     t[y]="";
                 }
             }
         }
         String[] fin=new String[t.length-merge];
         for(int i=0;i<t.length-merge;i++)
             fin[i]=t[i];
         return fin;
     }
     public class MyException extends Exception{
         public MyException(String str){
             JOptionPane.showMessageDialog(null, str,"警告", JOptionPane.INFORMATION_MESSAGE);
         }
     }
     //求两字符串数组合集个数。
     public int heji(String[] a,String[] b){
         int count=a.length+b.length;
         for(int i=0;i<a.length;i++)
         {
             for(int j=0;j<b.length;j++)
             {
                 if(a[i].equals(b[j]))
                     count--;
             }
         }
         return count;
     }
     //求两字符串数组交集个数。
     public int jiaoji(String[] a,String[] b){
         int count=0;
         for(int i=0;i<a.length;i++)
         {
             for(int j=0;j<b.length;j++)
             {
                 if(a[i].equals(b[j]))
                     count++;
             }
         }
         return count;
     }

 }

 package bigproject2;

 public class KShinglingAlgorithm extends union{
     private String text1,text2;
     public String getText1()
     {
         return text1;
     }
     public String getText2()
     {
         return text2;
     }
     public void setText1(String text1)
     {
         this.text1=text1;
     }
     public void setText2(String text2)
     {
         this.text2=text2;
     }

     public float getSimilarity(int k)
     {
        union a=new union();
        String[] t1=a.ziji(this.text1);
        String[] t2=a.ziji(this.text2);
        String[] t1t,t2t;
        try{
            t1t=a.cut(t1, k);
            t2t=a.cut(t2, k);

        }catch(MyException e){
                return -1;
        }
        int he=a.heji(t1t, t2t);
        int jiao=a.jiaoji(t1t, t2t);
        return (float)jiao/he;
     }

 }

面板设计部分：

 package bigproject2;
 import java.awt.*;
 import java.awt.event.*;
 import java.io.BufferedReader;
 import java.io.File;
 import java.io.FileNotFoundException;
 import java.io.FileReader;
 import java.io.IOException;
 import java.io.InputStreamReader;

 import javax.swing.*;
 import javax.swing.event.*;
 import javax.swing.filechooser.FileNameExtensionFilter;

 public class Outlook extends JFrame{
     JFrame frm=new JFrame("相似度计算器");
     JPanel areabottom=new JPanel();
     JPanel areatop=new JPanel();
     JPanel areamiddle=new JPanel();
     static JTextArea tl=new JTextArea();
     static JTextArea tr=new JTextArea();
     JScrollPane left=new JScrollPane(tl,JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,
             JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
     JScrollPane right=new JScrollPane(tr,JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,
             JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
     JSplitPane sp=new JSplitPane(JSplitPane.HORIZONTAL_SPLIT,left,right);
     static JButton toBig=new JButton("全部大写");
     static JButton delbd=new JButton("去掉标点");
     static JButton count=new JButton("计算相似度");
     JLabel space=new JLabel("                                               ");
     JLabel t1=new JLabel("Text1");
     JLabel t2=new JLabel("Text2");

     JMenuBar mb=new JMenuBar();
     JMenu open=new JMenu("打开");
     JMenuItem opent1=new JMenuItem("打开到Text1");
     JMenuItem opent2=new JMenuItem("打开到Text2");

     private String str="";
     public Outlook()
     {
         judge();

         frm.setVisible(true);
         frm.setBounds(50, 50, 500, 400);
         frm.setLayout(new BorderLayout(5,5));

         frm.add("North",areatop);
         frm.add("Center",areamiddle);
         frm.add("South",areabottom);

         areatop.add(mb);
         mb.add(open);
         open.add(opent1);
         open.add(opent2);
         open.setPreferredSize(new Dimension(40,18));
         mb.setBackground(frm.getBackground());
         areatop.setLayout(new FlowLayout(FlowLayout.LEFT));
         areamiddle.setLayout(new FlowLayout(FlowLayout.LEFT));

         areamiddle.add(t1);
         t1.setPreferredSize(new Dimension(frm.getWidth()/2-20,10));
         areamiddle.add(t2);
         t2.setPreferredSize(new Dimension(50,10));
         areamiddle.add(left);
         left.setPreferredSize(new Dimension(frm.getWidth()/2-20,frm.getHeight()/2));
         areamiddle.add(right);
         right.setPreferredSize(new Dimension(frm.getWidth()/2-20,frm.getHeight()/2));
         tl.setLineWrap(true);
         tr.setLineWrap(true);

         areabottom.add(toBig);
         areabottom.add(delbd);
         areabottom.add(space);
         areabottom.add(count);

         opent1.addActionListener(new ActionListener(){
             public void actionPerformed(ActionEvent e) {
                 try {
                     openfile();
                     tl.setText(str);
                 } catch (IOException e1) {
                     e1.printStackTrace();
                 }
                 judge();
             }
         });
         opent2.addActionListener(new ActionListener(){
             public void actionPerformed(ActionEvent e) {
                 try {
                     openfile();
                     tr.setText(str);
                 } catch (IOException e1) {
                     e1.printStackTrace();
                 }
                 judge();
             }
         });
         toBig.addActionListener(new ActionListener(){
             public void actionPerformed(ActionEvent e){
                 tl.setText(tobig(tl.getText()));
                 tr.setText(tobig(tr.getText()));
             }
         });

         delbd.addActionListener(new ActionListener(){
             public void actionPerformed(ActionEvent e){
                 tl.setText(del(tl.getText()));
                 tr.setText(del(tr.getText()));
                 judge();
             }

         });
         count.addActionListener(new ActionListener(){
             public void actionPerformed(ActionEvent e){
                 KShinglingAlgorithm a=new KShinglingAlgorithm();
                 a.setText1(tl.getText());
                 a.setText2(tr.getText());
                 float b=a.getSimilarity(4);
                 if(b!=-1)
                     JOptionPane.showMessageDialog(null, Float.toString(b),"相似度", JOptionPane.INFORMATION_MESSAGE);
             }
         });
         tr.addKeyListener(new KeyAdapter(){
             public void keyTyped(KeyEvent e){
                 judge();
             }
         });
         tl.addKeyListener(new KeyAdapter(){
             public void keyTyped(KeyEvent e){
                 judge();
             }
         });
     }
     public void judge(){
         if(tl.getText().length()!=0||tr.getText().length()!=0) {
             toBig.setEnabled(true);
             delbd.setEnabled(true);
             count.setEnabled(true);
         }
         else{
             toBig.setEnabled(false);
             delbd.setEnabled(false);
             count.setEnabled(false);
         }
     }
     public void openfile() throws IOException{
         str="";
         JFileChooser choose=new JFileChooser();
         int result = choose.showOpenDialog(this);
         File file = null; //注意初始化
         //加过滤器
         if (result == JFileChooser.APPROVE_OPTION) {
             file = choose.getSelectedFile();
             }
         else{
             return; //使点取消后不会抛出异常
         }
         FileReader fr=new FileReader(file);
         BufferedReader br=new BufferedReader(fr);
         char c[]=new char[512];
         String strline="";
         while(br.ready()){
             strline=br.readLine();
             str+=strline;
         };
         br.close();
         fr.close();
     }
     public String tobig(String str){
         String temp="";
         for(int i=0;i<str.length();i++)
         {
             if(str.charAt(i)>='a'&&str.charAt(i)<='z')
             {
                 char t=str.charAt(i);
                 t=(char)(str.charAt(i)-32);
                 temp+=t;
             }
             else temp+=str.charAt(i);
         }
         return temp;
     }

     public String del(String str){
         String temp="";
         for(int i=0;i<str.length();i++)
         {
             char t=str.charAt(i);
             if(t>='!'&&t<='/'||t>=58&&t<=64||t>=91&&t<=96||t>=123&&t<=126);
             else temp+=t;
         }
         return temp;
     }
     public static void main(String[] args){
         new Outlook();

     }
 }

Outlook