This IllegalStateException for these jar conflict happens when you choose library in you class path that are internally use log4j and slf4j.

In theory, If you are using log4j for logging, you could simply exclude the log4j-over-slf4j.jar because by using log4j,hacking other code to route the log4j calls to slf4j can lead to recursion and hence the strict check is there.

Stacktrace

Exception in thread "main" java.lang.ExceptionInInitializerError
    at org.slf4j.impl.StaticLoggerBinder.(StaticLoggerBinder.java:72)
    at org.slf4j.impl.StaticLoggerBinder.(StaticLoggerBinder.java:45)
    at org.slf4j.LoggerFactory.bind(LoggerFactory.java:150)
    at org.slf4j.LoggerFactory.performInitialization(LoggerFactory.java:124)
    at org.slf4j.LoggerFactory.getILoggerFactory(LoggerFactory.java:412)
    at org.slf4j.LoggerFactory.getLogger(LoggerFactory.java:357)
    at net.sourceforge.tess4j.Tesseract.(Tesseract.java:76)
    at imageread.ImageTextReading.crackImage(ImageTextReading.java:17)
    at imageread.ImageTextReading.main(ImageTextReading.java:9)
Caused by: java.lang.IllegalStateException: Detected both log4j-over-slf4j.jar AND bound slf4j-log4j12.jar on the class path, preempting StackOverflowError. See also http://www.slf4j.org/codes.html#log4jDelegationLoop for more details.
    at org.slf4j.impl.Log4jLoggerFactory.(Log4jLoggerFactory.java:54)
    ... 9 more

Solutions

From your class path or pom.xml exclude dependencies for log4j and slf4j as below.

In case of maven

<exclusions>
  <exclusion> 
    <groupId>org.slf4j</groupId>
    <artifactId>slf4j-log4j12</artifactId>
  </exclusion>
  <exclusion> 
    <groupId>log4j</groupId>
    <artifactId>log4j</artifactId>
  </exclusion>
</exclusions>

Incase of Gradle

compile('org.xxx:xxx:1.0-SNAPSHOT'){
    exclude module: 'log4j'
    exclude module: 'slf4j-log4j12'
}