一个网页打印文件的类（半成品）

    前天在公司写了个比较简单的页面打印文件信息的类，减少了JSP页面的复杂的。可惜不能带回家，今天回家就想做个更好的，可惜啊，花了太多时间去整了，最后的总结还是——这个类被使用的可能性还是不多的，而且还有点问题，传个JSP隐式对象out过去调用他的println不知道怎么第一行老是有大堆空格，目前还没有看那个编译之后的*_JSP.java类里面怎么打印的。暂时寄放在此。这个类还是可以使用的，只是暂时不知道应该提供哪些功能给它。其实还是学到不少新的知识。关于IO，jsp,集合，数组方面都有更多的了解。希望大家提出宝贵意见，要是您是初学者的话，有什么疑问我也很乐意解答和讨论。

    更好的做法，以后可以使用tag标签调用就好了。

 

 

package sc.sphenic.jsp.io;

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

import javax.servlet.jsp.JspWriter;

public class FileJSPWriter {
 private final int ARRAY_GRANT = 10;

 // public static void main(String args[]) {
 // String fileName = "c:/text.txt";
 // try {
 // FileJSPWriter.writeln(new JSPWriter(100, true), fileName);
 // FileJSPWriter out = new FileJSPWriter(new JSPWriter(100, true),
 // fileName);
 //
 // while (out.writeLine() != null) {
 // System.out.println();
 // System.out.println(out.getCurRow());
 // }
 // String[] lines = out.getLines();
 // for (int i = 0; i < lines.length; i++) {
 // System.out.println(lines[i]);
 // }
 // } catch (FileNotFoundException e) {
 // // TODO Auto-generated catch block
 // e.printStackTrace();
 // } catch (PageIOException e) {
 // // TODO Auto-generated catch block
 // e.printStackTrace();
 //  }
 // }

 private String[] lines = new String[ARRAY_GRANT];

 
 private int maxRow;

 
 private JspWriter out;

 
 private BufferedReader in;

 
 private String curLine;

 
 private int curRow;

 private int nxtRow;

 public FileJSPWriter(JspWriter out, File f) throws FileNotFoundException {
  setIn(f);
  setOut(out);
  // TODO Auto-generated constructor stub
 }

 void setOut(JspWriter out) {
  this.out = out;

 }

 boolean absolute(int row) throws PageIOException, PageFileException {
  try {
   String temp = lines[row - 1];
   if (temp != null) {
    curLine = temp;
    curRow = row + 1;
    nxtRow = curRow + 1;
    return true;
   } else {
    throw new ArrayIndexOutOfBoundsException();
   }

  } catch (java.lang.ArrayIndexOutOfBoundsException e) {
   // try to find in file
   while (readLine()) {
    if (!EOF()) {
     if (row == maxRow) {// line found
      return true;
     }

    } else {
     throw new PageFileException("Can not found the line in:"
       + row + "\n The max lines is :" + maxRow);
    }
   }
   return false;
  }

 }

 public boolean EOF() {
  return curLine == null;
 }

 
 public FileJSPWriter(JspWriter out, String filePath)
   throws FileNotFoundException {
  this(out, new File(filePath));
 }

 
 public static void writeln(JspWriter out, File f)
   throws FileNotFoundException, PageIOException {
  FileJSPWriter fOut = new FileJSPWriter(out, f);
  while (fOut.writeLine() != null) {
   // do nothing
  }
 }

 
 public static void writeln(JspWriter out, String filePath)
   throws FileNotFoundException, PageIOException {
  writeln(out, new File(filePath));
 }

 
 public String writeLine() throws PageIOException {
  if (getLine()) {
   try {
    out.println(curLine);
   } catch (IOException e) {
    throw new PageIOException(e);
   }
  }
  return curLine;
 }

 public boolean writeLine(File f, boolean bReplace) throws PageIOException,
   FileNotFoundException {
  checkReader(f, bReplace);
  return writeLine() != null;
 }

 private void checkReader(File f, boolean replace)
   throws FileNotFoundException {
  if (replace) {
   setIn(f);
  }
  if (in != null) {

  }
 }

 
 void setIn(File f) throws FileNotFoundException {
  in = new BufferedReader(new FileReader(f));
 }

 
 private boolean getLine() throws PageIOException {
  try {
   return absolute(curRow + 1);
  } catch (PageFileException e) {// EOF
   return false;
  }

 }

 private boolean readLine() throws PageIOException {
  // 文件到达最后readLine将返回null
  try {
   if ((curLine = in.readLine()) == null) {
    return false;
   } else {
    updateRow();
    return true;
   }
  } catch (IOException e) {
   try {
    in.close();
   } catch (IOException e1) {
    throw new PageIOException("Close reader error");
   }
   throw new PageIOException(e);
  }

 }

 public boolean getLine(int absoluteRow) throws PageIOException,
   PageFileException {

  if (absoluteRow < curRow) {
   absolute(absoluteRow);
   return true;
  } else {
   return readLine();
  }

 }

 private void updateRow() {
  if (lines.length == maxRow) {// out of index

   // extends the array
   extendLines();
  }
  lines[maxRow] = curLine;
  curRow++;
  maxRow++;
 }

 private void extendLines() {
  String[] src = lines;
  lines = new String[src.length + ARRAY_GRANT];
  System.arraycopy(src, 0, lines, 0, src.length);
 }

 void resetAllRow() {
  maxRow = 0;
  curRow = 0;
  nxtRow = curRow + 1;
 }

 public int getCurRow() {
  return curRow;
 }

 public String[] getLines() {
  return lines;
 }

}