Add an Ant build file to help with the Ant-Build-Matrix on Jenkins

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@1296674 13f79535-47bb-0310-9956-ffa450edef68

launch-build.xml

@@ -0,0 +1,40 @@
+<?xml version="1.0"?>
+<!--
+   Licensed to the Apache Software Foundation (ASF) under one or more
+   contributor license agreements.  See the NOTICE file distributed with
+   this work for additional information regarding copyright ownership.
+   The ASF licenses this file to You under the Apache License, Version 2.0
+   (the "License"); you may not use this file except in compliance with
+   the License.  You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+-->
+<project name="launch-build" default="launch">
+
+    <description>
+        Build file be able to launch the boostrap build of Ant on every supported platform
+    </description>
+
+    <condition property="launch.cmd" value="./build.sh">
+        <os family="unix" />
+    </condition>
+    <condition property="launch.cmd" value="build.bat">
+        <os family="windows" />
+    </condition>
+
+    <target name="launch">
+        <fail unless="launch.cmd" message="Unsupported build platform" />
+        <!-- by default no args, overridable on the Ant command line with -Dargs="" -->
+        <property name="args" value="" />
+        <echo message="Launching ${launch.cmd} ${args}" />
+        <exec command="${launch.cmd}" failonerror="true">
+            <arg line="${args}" />
+        </exec>
+    </target>
+</project>