可執行jar中的Apache POI

Question

我的程序成功運行了Apache POI功能以讀取Excel文件。 當我使用java類名運行它時，它可以正常工作。 當我打包為可執行jar時，它不起作用。 這是我不斷收到的錯誤消息：

java -jar some.jar

Error: A JNI error has occurred, please check your installation and try again
Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/poi/ss/usermodel/Row
    at java.lang.Class.getDeclaredMethods0(Native Method)
    at java.lang.Class.privateGetDeclaredMethods(Class.java:2701)
    at java.lang.Class.privateGetMethodRecursive(Class.java:3048)
    at java.lang.Class.getMethod0(Class.java:3018)
    at java.lang.Class.getMethod(Class.java:1784)
    at sun.launcher.LauncherHelper.validateMainClass(LauncherHelper.java:544)
    at sun.launcher.LauncherHelper.checkAndLoadMain(LauncherHelper.java:526)
Caused by: java.lang.ClassNotFoundException: org.apache.poi.ss.usermodel.Row
    at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:349)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)

當我正常運行它時，它工作正常，例如

java a.e

我從閱讀堆棧溢出知道知道我有poi-ooxml和xmlbeans 。 （20688851，15831591）

這是我的可執行jar根目錄中的jar文件。

5924600 Wed Sep 12 13:02:26 CDT 2018 poi-ooxml-schemas-3.17.jar
1479023 Wed Sep 12 13:02:26 CDT 2018 poi-ooxml-3.17.jar
1390360 Tue Oct 02 13:04:14 CDT 2018 poi-scratchpad-3.17.jar
313359 Tue Oct 02 13:17:34 CDT 2018 dom4j.jar
 25863 Tue Oct 02 13:19:46 CDT 2018 stax-api.jar
1950905 Wed Sep 12 13:02:26 CDT 2018 poi-3.10-FINAL-20140208.jar
2730866 Tue Oct 02 12:43:34 CDT 2018 xmlbeans-2.6.0.jar

這是我演示該問題的最小測試用例。

package a;
import java.io.*;
import java.lang.*;
import java.lang.reflect.*;
import java.util.*;

public class e {

    static PrintWriter F;
    static FileInputStream ConfigurationFile; 
        static String iSheet = "TAB2";

    private static final String strResourceName = "11in35tr.xls";


    static
    {
            java.io.InputStream streamData = null;
            try
            {
                            streamData=a.e.class.getResourceAsStream(strResourceName);
            }
            catch(NullPointerException e)
            {
                System.out.println("Unable to load the resource stream for '" + strResourceName + "'");

                assert false;
            }
System.out.println (" stream Data |"  + streamData+"|");
            org.apache.poi.hssf.usermodel.HSSFWorkbook workbook = null;
            try
            {
                workbook = new org.apache.poi.hssf.usermodel.HSSFWorkbook(streamData);
            }
            catch(java.io.IOException e)
            {
                System.out.println("Unable to create a HSSFWorkbook for the stream.  Is it really an Excel file?");

                assert false;
            }
                        String Sheet;
            org.apache.poi.hssf.usermodel.HSSFSheet sheet = workbook.getSheet(iSheet);
            if(sheet == null) {
                System.out.println("While we were able to open the resource as an Excel file, it doesn't appear to contain sheet " + sheet.toString() + " as specified in the config file");
                       }
               for(int iCurRow = 0;iCurRow<3;iCurRow++)
                {
                    org.apache.poi.ss.usermodel.Row rowCur = sheet.getRow(iCurRow);
                    if(rowCur == null)
                    {
                        System.out.println("We're supposed to get a row title from row " + 
                          Integer.toString(iCurRow) + " in sheet " + iSheet + ", but that row doesn't exist");

                        break;
                    }
for (int iCol=0;iCol<3;iCol++) {
                    org.apache.poi.ss.usermodel.Cell 
cellWithTitle = rowCur.getCell(iCol);
                    if(cellWithTitle == null)
                    {
                        System.out.println("We're supposed to get a row title from cell " + Integer.toString(iCol) + " in row " + Integer.toString(iCurRow) + " in sheet " + iSheet + ", but that column doesn't appear to exist in the specified sheet.");

                        break;
                    }
                String strNewRowTitle = cellWithTitle.toString();

                System.out.println("Created row: '" + strNewRowTitle + "'");
}
            } // for


    } // end of static

   static void Init () throws java.io.IOException {
      ConfigurationFile = new FileInputStream ("config.in");
      F = new PrintWriter (new FileOutputStream ("config.out"));
   }

     public static void main (String args[]) throws IOException {
        Init();

        F.close();
    }
}

---

不幸的是，這些無效。 首先，我更新了manifest.txt文件。 （如..所示）

Main-Class: a.c
Class-path: poi-ooxml-schemas-3.17.jar poi-ooxml-3.17.jar poi-scratchpad-3.17.jar dom4j.jar stax-api.jar poi-3.10-FINAL-2014028.jar xmlbeans-2.6.0.jar

然后，我嘗試了命令

java -classpath *.jar -jar some.jar 
java -classpath "poi-ooxml-schemas-3.17.jar:poi-ooxml-3.17.jar:poi-scatchpad-3.17.jar:dom4.jar:stax-api.jar:poi-3.10-FINAL-2014028.jar:xmlbeans-2.6.0.jar" -jar some.jar

我的理解是，當我們使用可執行jar時，-classpath被忽略。

因此，在下載了我在原始帖子中列出的一組罐子之后，我確實嘗試了以下變化。

set CLASSPATH=".;poi-ooxml-schemas-3.17.jar;poi-ooxml-3.17.jar;poi-scatchpad-3.17.jar;dom4.jar;stax-api.jar;poi-3.10-FINAL-2014028.jar;xmlbeans-2.6.0.jar" 
echo %CLASSPATH%
java a.e

他們以同樣的方式失敗。 但是，我可以在Linux系統上很好地運行該程序。 因此，很顯然，LINUX系統上POI需要的東西不在Windows計算機上。

（請注意，ae在LINUX上運行良好。它無法在PC ==上運行，因此我在LINUX中設置的環境需要某些東西，但不知道那是什么。但是，我也再次檢查了將ae放入可執行jar並在同一LINUX環境上運行它。它會產生相同的問題。）

當然，我也嘗試從poi.apache.org下載新的4.0， poi.apache.org六個jar文件包含在zip文件poi-bin-4.0.0...zip ）

Answer 1

您有2個職位

將這些jar包含在您的jar中，並在META-INF / MANIFEST.MF中設置類路徑

Manifest-Version: 1.0
Class-Path: file1.jar file2.jar file3.jar

或在調用Java時將這些jar添加到classpath

java -classpath \path_to_jars\*.jar your.package.YourMainClass