The Java interface to the dtSearch Engine is based on the Java Native Interface (JNI). Therefore, both the Java classes and a platform-specific binary executable are needed to use it.
The Java classes are in examples\java\classes\dtSearchEngine.jar, which must be on the CLASSPATH. Adding the dtSearch Engine examples/java/classes folder to the CLASSPATH, or copying its contents to a folder on the CLASSPATH, will make these classes available in Java.
For information on setting up the platform-specific binary executable, please see:
For general information on using the dtSearch Engine API, such as the search request syntax, procedures for building and maintaining indexes, and options settings, see the Overviews section in dtSearchApiRef.chm.