sudo R CMD javareconf
[sudo] password for masi:
Java interpreter : /usr/lib/jvm/default-java/jre/bin/java
Java version     : 1.8.0_131
Java home path   : /usr/lib/jvm/default-java
Java compiler    : not present
Java headers gen.:
Java archive tool: /usr/bin/jar

trying to compile and link a JNI program
detected JNI cpp flags    :
detected JNI linker flags : -L$(JAVA_HOME)/jre/lib/amd64/server -ljvm
gcc -std=gnu99 -I/usr/share/R/include -DNDEBUG      -fpic  -g -O2 -fdebug-prefix-map=/home/jranke/git/r-backports/stretch/r-base-3.4.0=. -fstack-protector-strong -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2 -g  -c conftest.c -o conftest.o
conftest.c:1:17: fatal error: jni.h: No such file or directory
 #include <jni.h>
                 ^
compilation terminated.
/usr/lib/R/etc/Makeconf:159: recipe for target 'conftest.o' failed
make: *** [conftest.o] Error 1
Unable to compile a JNI program


JAVA_HOME        : /usr/lib/jvm/default-java
Java library path:
JNI cpp flags    :
JNI linker flags :
Updating Java configuration in /usr/lib/R
Done.