RosettaCodeData/Task/Read-a-configuration-file/Java/read-a-configuration-file-1...

71 lines
2.3 KiB
Java

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 ) );
}
}
}