Add a task to load the native environment into some properties with a specified prefix

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@270524 13f79535-47bb-0310-9956-ffa450edef68

proposal/myrmidon/src/java/org/apache/antlib/nativelib/LoadEnvironment.java

@@ -0,0 +1,102 @@
+/*
+ * Copyright (C) The Apache Software Foundation. All rights reserved.
+ *
+ * This software is published under the terms of the Apache Software License
+ * version 1.1, a copy of which has been included with this distribution in
+ * the LICENSE.txt file.
+ */
+package org.apache.antlib.nativelib;
+
+import java.io.IOException;
+import java.util.Iterator;
+import java.util.Properties;
+import org.apache.avalon.excalibur.i18n.ResourceManager;
+import org.apache.avalon.excalibur.i18n.Resources;
+import org.apache.myrmidon.api.AbstractTask;
+import org.apache.myrmidon.api.TaskException;
+import org.apache.myrmidon.framework.exec.Environment;
+import org.apache.myrmidon.framework.exec.ExecException;
+
+/**
+ * This task is responsible for loading that OS-specific environment
+ * variables and adding them as propertys to the context with a specified
+ * prefix.
+ *
+ * @author <a href="mailto:peter@apache.org">Peter Donald</a>
+ */
+public class LoadEnvironment
+    extends AbstractTask
+{
+    private static final Resources REZ =
+        ResourceManager.getPackageResources( LoadEnvironment.class );
+
+    private String m_prefix;
+
+    public void setPrefix( final String prefix )
+    {
+        m_prefix = prefix;
+    }
+
+    public void execute()
+        throws TaskException
+    {
+        if( null == m_prefix )
+        {
+            final String message = REZ.getString( "loadenv.no-prefix.error" );
+            throw new TaskException( message );
+        }
+
+        //Make sure prefix ends with a '.'
+        if( !m_prefix.endsWith( "." ) )
+        {
+            m_prefix += ".";
+        }
+
+        if( getLogger().isDebugEnabled() )
+        {
+            final String displayPrefix =
+                m_prefix.substring( 0, m_prefix.length() - 1 );
+            final String message =
+                REZ.getString( "loadenv.prefix.notice", displayPrefix );
+            getLogger().debug( message );
+        }
+
+        final Properties environment = loadNativeEnvironment();
+        final Iterator keys = environment.keySet().iterator();
+        while( keys.hasNext() )
+        {
+            final String key = (String)keys.next();
+            final String value = environment.getProperty( key );
+
+            if( value.equals( "" ) )
+            {
+                final String message = REZ.getString( "loadenv.ignoring-empty.warn", key );
+                getLogger().warn( message );
+            }
+            else
+            {
+                getContext().setProperty( m_prefix + key, value );
+            }
+        }
+    }
+
+    /**
+     * Utility method to load the native environment variables.
+     */
+    private Properties loadNativeEnvironment()
+        throws TaskException
+    {
+        try
+        {
+            return Environment.getNativeEnvironment();
+        }
+        catch( final ExecException ee )
+        {
+            throw new TaskException( ee.getMessage(), ee );
+        }
+        catch( final IOException ioe )
+        {
+            throw new TaskException( ioe.getMessage(), ioe );
+        }
+    }
+}

proposal/myrmidon/src/java/org/apache/antlib/nativelib/Resources.properties

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+loadenv.no-prefix.error=No prefix specified for environment data.
+loadenv.prefix.notice=Loading Environment with prefix {0}.
+loadenv.ignoring-empty.warn=Key {0} in native OS environment is empty - ignoring key.