可执行jar中的Apache POI [英] Apache POI in executable jar
问题描述
我的程序成功运行Apache POI功能以读取 Excel文件.当我使用java类名运行它时，它可以正常工作. 当我打包为可执行jar时，它不起作用.这里是 我不断收到错误消息:
My program successfully runs the Apache POI functionality to read Excel Files. It works fine when I run it with java class name. When I package as an executable jar it does not work. Here is the error message I keep getting:
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)
正常运行时，它可以正常工作，例如g.
It works fine when I run it normally, e. g.
java a.e
我从阅读堆栈溢出中知道，以确保我有
poi-ooxml和xmlbeans. (20688851，15831591)
I know from reading stack overflow to be sure that I have
poi-ooxml and xmlbeans. (20688851, 15831591)
这是我的可执行jar根目录中的jar文件.
Here are the jar files in the root of my executable jar.
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
这是我演示该问题的最小测试用例.
Here is my minimal test case that demonstrates the problem.
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，这些无效.首先，我更新了manifest.txt文件. (如所示)
Unfortunately, these do not work. At first, I updated the manifest.txt file. (as indicated)
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，我尝试了该命令
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，当我们使用可执行jar时，-classpath会被忽略.
My understanding is that -classpath is ignored when we use an executable jar.
因此，在下载了我在原始帖子中列出的一组罐子之后，我确实尝试了以下变化.
Thus, I did try variations on the following, after download the set of jars that I listed in the original post.
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
它们以相同的方式失败.但是，我可以在Linux系统上很好地运行该程序.因此，显然有一些东西 在Windows计算机上不在POI所需的LINUX系统上.
They fail the same way. However, I can run the program fine on the Linux system. Thus, apparently, there is something on the LINUX system that the POI needs that is not on the Windows computer.
(注意a.e在LINUX上运行良好.它不能在PC ==上运行，因此在我在LINUX上设置的环境中需要一些东西，但不知道那是什么. 但是，我还再次检查了将a.e放入可执行jar并在相同的LINUX环境中运行它.会产生同样的问题.)
(Note a.e runs fine on LINUX. It does not run on the PC== so something is needed on that environment that I set up in LINUX, but don't know what that is. However, i also checked again putting the a.e in an executable jar and running it on the same LINUX environment. It generates the same problem.)
当然，我也尝试从poi.apache.org下载新的4.0，并将六个jar文件包含在zip文件poi-bin-4.0.0...zip中)
Of course, I also tried getting the new 4.0 download from poi.apache.org and including the six jar files in the zip file poi-bin-4.0.0...zip)
推荐答案
您有2种可能性
将这些jar包含在您的jar中，并在META-INF/MANIFEST.MF中设置类路径
Include those jars inside yours and set classpath inside META-INF/MANIFEST.MF
Manifest-Version: 1.0
Class-Path: file1.jar file2.jar file3.jar
或在调用Java时将这些jar添加到classpath
or on your call to java add those jars to classpath
java -classpath \path_to_jars\*.jar your.package.YourMainClass
这篇关于可执行jar中的Apache POI的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
