Opencv430.jar was not created after cmake [closed]
So i was building Opencv 4.3. on my Ubuntu 20.04 and followed the Tutorials: Installation on Linux & Introduction to Java Development. I get a build, but Opencv430.jar is no created. Here is the cmake output:
Could not find OpenBLAS include. Turning OpenBLAS_FOUND off
Could not find OpenBLAS lib. Turning OpenBLAS_FOUND off
Could NOT find Atlas (missing: Atlas_CBLAS_INCLUDE_DIR Atlas_CLAPACK_INCLUDE_DIR Atlas_CBLAS_LIBRARY
Atlas_BLAS_LIBRARY Atlas_LAPACK_LIBRARY)
Could NOT find BLAS (missing: BLAS_LIBRARIES)
LAPACK requires BLAS
A library with LAPACK API not found. Please specify library location.
Error: Could not find or load main class org.apache.tools.ant.launch.Launcher
Caused by: java.lang.ClassNotFoundException: org.apache.tools.ant.launch.Launcher
OpenCV modules:
To be built: calib3d core features2d flann gapi highgui imgcodecs imgproc ml objdetect photo stitching ts video videoio
Disabled: python_bindings_generator python_tests world
Disabled by dependency: -
Unavailable: dnn java js python2 python3
Applications: apps
Documentation: NO
Non-free algorithms: NO
Java:
ant: NO
JNI: /usr/lib/jvm/java-14-openjdk-amd64/include /usr/lib/jvm/java-14-openjdk-amd64/include/linux /usr/lib/jvm/java-14-openjdk-amd64/include
Java wrappers: NO
Java tests: NO
So, Java is unavailable, because ant is missing. Which is strange, because it is installed. I checked the enviroment variable and got /usr/bin/ant. Thought the link was to blame and made it explicit. Change the $ANT_HOME to /usr/share/ant/bin
What do i need to do to get a build, that has the Java Module?
yes, you need the ant tool
if you can start
ant
from a console, cmake can too. if you can't -- try harderI don't understand it. I build Opencv-4.3. on an other machine. Same Setting, Same cmake options and it worked. I was trying to build it on the old machine as well, but it failed again.