[Buildroot] [PATCH v6 3/4] dependencies.sh: Introduce BR2_HOST_NEEDS_JAVA

[Maxime Hadjinlian]

XBMC needs Java on the host in order to build, because it  uses a
code-generator which is build in two phases:
In the first phase SWIG is used to parse C++ header files that define the API.
SWIG outputs an XML file that contains a complete description of the structure
of the API.
In the second phase, the XML file is ingested by a Groovy (Java) program that
then creates C++ code that forms the bridge to the scripting language (Python).

The second phase is why we need java on the host.

You can learn more at the XBMC's wiki:
http://wiki.xbmc.org/index.php?title=Codegeneration#How_it_works

In order to check that, this patch introduce this mechanism in
dependencies.sh

Signed-off-by: Maxime Hadjinlian <maxime.hadjinlian at gmail.com>
---
Changes v5 -> v6:
  - Remove useless loop (Thomas Petazzoni)
  - Thanks to Martin Bark idea, change this patch to have a non package
    specific variable.
Changes v1 -> v5:
  - Patch non existant before
---
 support/dependencies/dependencies.sh | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/support/dependencies/dependencies.sh b/support/dependencies/dependencies.sh
index 0e7e1fa..dd90bee 100755
--- a/support/dependencies/dependencies.sh
+++ b/support/dependencies/dependencies.sh
@@ -191,6 +191,14 @@ if grep -q ^BR2_PACKAGE_CLASSPATH=y $BR2_CONFIG ; then
 	done
 fi
 
+if grep -q ^BR2_HOST_NEEDS_JAVA=y $BUILDROOT_CONFIG ; then
+	if ! which java > /dev/null ; then
+		echo >&2
+		echo "You must install '$prog' on your build machine" >&2
+		exit 1
+	fi
+fi
+
 if grep -q ^BR2_HOSTARCH_NEEDS_IA32_LIBS=y $BR2_CONFIG ; then
 	if test ! -f /lib/ld-linux.so.2 ; then
 		echo
-- 
1.8.5.3