java tess4j ddl,分配为war NoClassDefFoundError后出现Tess4J错误：无法初始化类net.sourceforge.tess4j.TessAPI…「建议收藏」

I have Spring boot Webserver project which works ok in my PC under Intellij IDEA, but it not works after distributing to the same PC as war file – NoClassDefFoundError: Could not initialize class net.sourceforge.tess4j.TessAPI.

my code:

ITesseract instance = new Tesseract(); // JNA Interface Mapping

instance.setDatapath(new File(datapath).getPath());

instance.setLanguage(“eng”);

try {

String result = instance.doOCR(imageFile);

} catch (TesseractException e) {

System.err.println(e.getMessage());

}

I have only one maven dependency, releted to Tess4J:

net.sourceforge.tess4j

tess4j

3.0.0

I’ve got the error after running my distributed war:

There was an unexpected error (type=Internal Server Error, status=500).

Could not initialize class net.sourceforge.tess4j.TessAPI

Full Tomcat log:

java.lang.NoClassDefFoundError: Could not initialize class net.sourceforge.tess4j.TessAPI

at net.sourceforge.tess4j.Tesseract.init(Tesseract.java:367) ~[tess4j-3.0.0.jar:3.0.0]

at net.sourceforge.tess4j.Tesseract.doOCR(Tesseract.java:280) ~[tess4j-3.0.0.jar:3.0.0]

at net.sourceforge.tess4j.Tesseract.doOCR(Tesseract.java:212) ~[tess4j-3.0.0.jar:3.0.0]

at net.sourceforge.tess4j.Tesseract.doOCR(Tesseract.java:196) ~[tess4j-3.0.0.jar:3.0.0]

at ocr.OCRController.handleFileUpload(OCRController.java:127) ~[classes/:0.3.0]

at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_51]

at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_51]

at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_51]

at java.lang.reflect.Method.invoke(Method.java:497) ~[na:1.8.0_51]

at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:222) ~[spring-web-4.2.3.RELEASE.jar:4.2.3.RELEASE]

at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:137) ~[spring-web-4.2.3.RELEASE.jar:4.2.3.RELEASE]

at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:110) ~[spring-webmvc-4.2.3.RELEASE.jar:4.2.3.RELEASE]

How can I fix the error? I have the plan to host this app in Windows Azure under Tomcat. Thank you for any help, friends!

解决方案

The problem was in temp folder – it does not contain all necessary dlls.

Info for community:

1. Check temp folder under tomact – for me the path to it is:

D:\Programs_Files\apache-tomcat-8.0.27\temp

This temp folder MUST contain the directory tess4j\win32-x86-64 with next 3 files: gsdll64.dll, liblept171.dll, libtesseract304.dll (or your version)

I had my problem because the directory tess4j\win32-x86-64 have never been created in temp.

BUT

My app works ok under Intellij IDEA because another Temp folder (for IDEA) works ok – C:\Users\Iuliia\AppData\Local\Temp\

contains tess4j\win32-x86-64\gsdll64.dll, tess4j\win32-x86-64\liblept171.dll, tess4j\win32-x86-64\libtesseract304.dll as expected.

Note, that this files are created in process of calling Tesseract in your code. Not early.

HOW I FIX THE PROBLEM with temp under Tomcat

I’ve added win32-x86-64\gsdll64.dll, win32-x86-64\liblept171.dll, win32-x86-64\libtesseract304.dll to the resources directory in my project.

Look at my project structure:

After deploying to tomcat, the necessary dlls is under classes directory (important!) – it means they are is in the scope.

Now it will be added to

D:\Programs_Files\apache-tomcat-8.0.27\temp\tess4j\win32-x86-64 as expected.