configure

#! /bin/sh
## For the time being, this is a simple shell script ...

## Find the R home directory.
: ${R_HOME=`R RHOME`}
if test -z "${R_HOME}"; then
  echo "Could not determine R_HOME."
  exit 1
fi

## Find the configured Java interpreter.
## If JAVA is set in the environment, use it.
if test -z "${JAVA}" || test ! -x "${JAVA}"; then
  ## Argh.  R CMD config JAVA works only from 2.5.0 onwards ...
  JAVA=`"${R_HOME}/bin/R" CMD config | grep JAVA`
  if test -n "${JAVA}"; then
    JAVA=`"${R_HOME}/bin/R" CMD config JAVA`
  fi
  if test -z "${JAVA}" || test ! -x "${JAVA}"; then
    ## Keep this in sync with what is used in R CMD javareconf.
    ## Sort of ...
    JAVA_PATH="${PATH}"
    if test -n "${JAVA_HOME}" && test -d "${JAVA_HOME}"; then
      JAVA_PATH="${JAVA_HOME}:${JAVA_HOME}/jre/bin:${JAVA_HOME}/bin:${JAVA_PATH}"
    fi
    JAVA_PATH="${JAVA_PATH}":/usr/java/bin:/usr/jdk/bin:/usr/lib/java/bin:/usr/lib/jdk/bin:/usr/local/java/bin:/usr/local/jdk/bin:/usr/local/lib/java/bin:/usr/local/lib/jdk/bin
    save_IFS="${IFS}"
    IFS=":"
    for dir in ${JAVA_PATH}; do
      test "${dir}" = "." && continue
      if test -x "${dir}/java"; then
        JAVA="${dir}/java"
        break
    fi
    done
    IFS="${save_IFS}"
  fi
  if test -z "${JAVA}"; then
    echo "Could not determine the Java interpreter."
    echo "Maybe run R CMD javareconf?"
    exit 1
  fi
fi

## Check Java version requirement.
RWeka_cv_java_version_8=no
## See <http://openjdk.java.net/jeps/223>.
java_version=`${JAVA} -cp tools getsp "java.version" | sed 's/[+-].*//'`
java_version_maj=`echo "${java_version}" | cut -f1 -d.`
java_version_min=`echo "${java_version}" | cut -f2 -d.`
if test ${java_version_maj} -ge 8 || \
    { test ${java_version_maj} -eq 1 && \
      test ${java_version_min} -ge 8; } ;
then
  RWeka_cv_java_version_8=yes
fi

if test "${RWeka_cv_java_version_8}" = no; then
  echo "Need at least Java version 8."
  exit 1
fi