March 2014 update

Task/Read-a-configuration-file/Java/read-a-configuration-file.java

@@ -0,0 +1,70 @@
+import java.io.BufferedReader;
+import java.io.FileReader;
+import java.io.IOException;
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+public class ConfigReader {
+    private static final Pattern             LINE_PATTERN = Pattern.compile( "([^ =]+)[ =]?(.*)" );
+    private static final Map<String, Object> DEFAULTS     = new HashMap<String, Object>() {{
+        put( "needspeeling", false );
+        put( "seedsremoved", false );
+    }};
+
+    public static void main( final String[] args ) {
+        System.out.println( parseFile( args[ 0 ] ) );
+    }
+
+    public static Map<String, Object> parseFile( final String fileName ) {
+        final Map<String, Object> result = new HashMap<String, Object>( DEFAULTS );
+        /*v*/ BufferedReader      reader = null;
+
+        try {
+            reader = new BufferedReader( new FileReader( fileName ) );
+            for ( String line; null != ( line = reader.readLine() );  ) {
+                parseLine( line, result );
+            }
+        } catch ( final IOException x ) {
+            throw new RuntimeException( "Oops: " + x, x );
+        } finally {
+            if ( null != reader ) try {
+                reader.close();
+            } catch ( final IOException x2 ) {
+                System.err.println( "Could not close " + fileName + " - " + x2 );
+            }
+        }
+
+        return result;
+    }
+
+    private static void parseLine( final String line, final Map<String, Object> map ) {
+        if ( "".equals( line.trim() ) || line.startsWith( "#" ) || line.startsWith( ";" ) )
+            return;
+
+        final Matcher matcher = LINE_PATTERN.matcher( line );
+
+        if ( ! matcher.matches() ) {
+            System.err.println( "Bad config line: " + line );
+            return;
+        }
+
+        final String key   = matcher.group( 1 ).trim().toLowerCase();
+        final String value = matcher.group( 2 ).trim();
+
+        if ( "".equals( value ) ) {
+            map.put( key, true );
+        } else if ( -1 == value.indexOf( ',' ) ) {
+            map.put( key, value );
+        } else {
+            final String[] values = value.split( "," );
+
+            for ( int i = 0; i < values.length; i++ ) {
+                values[ i ] = values[ i ].trim();
+            }
+            map.put( key, Arrays.asList( values ) );
+        }
+    }
+}