poi(2)解析jar并写入excel

最新推荐文章于 2022-11-02 22:53:54 发布

转载最新推荐文章于 2022-11-02 22:53:54 发布 · 1.5k 阅读

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本文介绍了一种从Java归档(JAR)文件中提取类信息，并将这些信息写入Excel电子表格的方法。主要涵盖了如何读取JAR文件中的类名、成员变量及声明的方法，并以结构化的方式展示。

解析jar并写入excel

package pois;
import java.util.jar.*;
import java.util.*;
import java.util.zip.ZipEntry;

import java.lang.reflect.Field;
import java.lang.reflect.Method;

import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFCellStyle;
import org.apache.poi.hssf.usermodel.HSSFFont;
import org.apache.poi.hssf.util.HSSFColor;

import java.io.FileOutputStream;
/**
* This class would extract information
* from a Java Archive File and write information
* about the classes into an Excel Sheet.
* The key information generated are the following 
* a) The class Name in First Column 
* b) The Class Member Fields in second column 
* c) The Declared Methods in Third column 
* The Java archive file and the Output File Location
* must be passed in as parameters
*
*/
public class JavaExtract {

 /** Creates a new instance of JavaExtract */
 public JavaExtract() {
 }
 /** Name of the input Jar File */
 public String jarFile=null;
 /** Where the ouput XL should be written */
 public String outputFile=null;
 /** The XL Document */
 HSSFWorkbook workbook = new HSSFWorkbook();
 /** The XL Sheet */
 HSSFSheet sheet = null;

 /* Creates an instance and Initializes the same */
 public static void main(String argv[]){
 JavaExtract jE = new JavaExtract();
 String dirs = "C://unzipped//poi-bin-2.5.1-final-20040804//";
 // Make sure you pass the
 jE.jarFile= System.getProperty("JAR_FILE");
 jE.jarFile = dirs + "poi-2.5.1-final-20040804.jar";
 jE.outputFile = System.getProperty("OUTPUT_FILE");
 jE.outputFile = dirs + "poi-2.5.xls";

 // Make sure that jarFile param is available
 if(jE.jarFile == null){
 System.out.println("The JAR_FILE parameter is not passed as a -DJAR_FILE ..");
 }
 // Make sure that output file name param is available
 if(jE.outputFile == null){
 System.out.println("The OUTPUT_FILE parameter is not passed as a -DOUTPUT_FILE ..");
 }
 // Create the workbook..
 jE.createWorkBookAndSheet();
 // Unzip and start writing
 jE.unZipAndWrite();
 // Create headers in the Excel Book
 jE.headers();
 // Write the XL Document to file..
 jE.writeToFile();
 System.out.println("Done.." );
 }

 /**
 * Creates an excel workbook & sheet and does column
 * formatting
 */
 public void createWorkBookAndSheet(){
 try{
 // Create a New XL Document
 workbook = new HSSFWorkbook();
 // Make a worksheet in the XL document created
 // Give a Name to the worksheet
 sheet = workbook.createSheet("Java Class Info");
 System.out.println("Work Sheet Created " );
 // Set the first three columns with
 // The width is in units of 1/256th of a character width
 sheet.setColumnWidth((short)0,(short)10000 );
 sheet.setColumnWidth((short)1,(short)10000 );
 sheet.setColumnWidth((short)2,(short)10000 );
 }catch(Exception e) {
 System.out.println("!!FAILURE!! createWorkBookAndSheet() : " + e );
 }
 }
 /**
 * This method will unzip the Zip file
 * and start writing in to excel..
 * The key information gererated are the following
 * a) The class Name in First Column 
 * b) The Class Member Fields in second column 
 * c) The Declared Methods in Third column 
 */
 public void unZipAndWrite(){
 try{
 JarFile jF = new JarFile(jarFile);
 Enumeration enum = jF.entries();
 ZipEntry zN = null;
 String fN = null;
 String clazName = null;
 String classLoadName = null;
 Class clz = null;
 short rowNum = 1;
 short cellNum = 0;
 while(enum.hasMoreElements()){
 try
 {
 zN = (ZipEntry)enum.nextElement();
 fN = zN.getName();
 if(fN.indexOf(".class")!= -1){
 // The class name contains /. Butto load class we need the
 // path to be separated by dot. So do the replace
 clazName = fN.replace('/', '.');
 // To Load class, we dont need the extension.. so
 // remove the .class from the classname
 classLoadName = clazName.substring(0,clazName.length() - 6);
 System.out.println("Process The Class --> " + classLoadName );
 // Create a Row
 HSSFRow row = sheet.createRow((short)rowNum);
 HSSFCell cell = row.createCell((short) cellNum);
 // Lets make the cell a string type
 cell.setCellType(HSSFCell.CELL_TYPE_STRING);

 // Write the Name of the Class in the first
 // column
 cell.setCellValue(classLoadName);

 // Begin Wringing the Declared classes
 // in the second coloumn
 cell = row.createCell((short) (cellNum+1) );
 // Load the class..
 clz = Class.forName(classLoadName, false , this.getClass().getClassLoader());
 //clz = Class.forName(classLoadName);

 Field[] fL = clz.getDeclaredFields();
 // Go Over the Fields and get the Names
 for(int i=0; i< fL.length;i++){
 // Keep appending the Name of the Field
 if(i==0){
 cell.setCellValue(fL[i].getName());
 }else {
 cell.setCellValue(cell.getStringCellValue()+ ", "+ fL[i].getName());
 }
 }

 cell = row.createCell((short) (cellNum+2) );
 // Lets make the cell a string type
 cell.setCellType(HSSFCell.CELL_TYPE_STRING);

 Method[] method = clz.getDeclaredMethods();
 for(int i=0; i< method.length;i++){
 // Keep appending the Name of the Field
 if(i==0){
 cell.setCellValue(method[i].getName());
 }else {
 cell.setCellValue(cell.getStringCellValue()+ ", "+ method[i].getName());
 }
 }
 // Go to the next line
 rowNum++;
 }// close if

 }catch (Exception innerEx){
 System.out.println("FAILURE!! unZipAndWrite() .. In proceessing file : " + innerEx );
 }
 }// close while

        }catch(Exception e) {
            System.out.println("!!FAILURE!! unZipAndWrite() : " + e );
        }
    }


    /**
     * Writes headers in the output file
     */
    public void headers(){
        try{
            HSSFRow row = sheet.createRow((short)0);
            // Set the correct font
            HSSFFont font = workbook.createFont();
            font.setColor(HSSFFont.COLOR_RED);
            font.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
            // Set the correct Style
            HSSFCellStyle cellStyle= workbook.createCellStyle();
            cellStyle.setFont(font);
            // Set the cell style for Class Name Heading Cell
            HSSFCell cell = row.createCell((short) 0);
            cell.setCellStyle(cellStyle);
            cell.setEncoding(HSSFCell.ENCODING_UTF_16);
            cell.setCellType(HSSFCell.CELL_TYPE_STRING);
            cell.setCellValue("类名称 ");
            // Set the cell style for Declared Fields Heading Cell
            cell = row.createCell((short) 1);
            cell.setCellStyle(cellStyle);
            cell.setCellType(HSSFCell.CELL_TYPE_STRING);
            cell.setCellValue("Declared Fields");
             // Set the cell style for Declared Methods Heading Cell
            cell = row.createCell((short) 2);
            cell.setCellStyle(cellStyle);
            cell.setCellType(HSSFCell.CELL_TYPE_STRING);
            cell.setCellValue("Declared Methods");
        }catch(Exception e) {
            System.out.println("!!FAILURE!! headers() : " + e );
        }

    }
    /**
     * Write the created excel document in to a file
     */
    public void writeToFile(){
        try{
            System.out.println("Write Output" );
            // The Output file is where the xls will be created
            FileOutputStream fOut = new FileOutputStream(outputFile);
            // Write the XL sheet
            workbook.write(fOut);
            fOut.flush();
            // Done Deal..Close it
            fOut.close();
            System.out.println("Done Writing" );
        }catch(Exception e) {
            System.out.println("!!FAILURE!! writeToFile() : " + e );
        }

    }
}