package org.apache.lucene.analysis.charfilter;
import java.io.IOException;
import java.io.Reader;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import org.apache.lucene.analysis.util.CharFilterFactory;
import org.apache.lucene.analysis.util.ResourceLoader;
import org.apache.lucene.analysis.util.ResourceLoaderAware;
public class MappingCharFilterFactory extends CharFilterFactory implements
ResourceLoaderAware {
public static final String NAME = "mapping";
protected NormalizeCharMap normMap;
private final String mapping;
public MappingCharFilterFactory(Map<String,String> args) {
super(args);
mapping = get(args, "mapping");
if (!args.isEmpty()) {
throw new IllegalArgumentException("Unknown parameters: " + args);
}
}
@Override
public void inform(ResourceLoader loader) throws IOException {
if (mapping != null) {
List<String> wlist = null;
List<String> files = splitFileNames(mapping);
wlist = new ArrayList<>();
for (String file : files) {
List<String> lines = getLines(loader, file.trim());
wlist.addAll(lines);
}
final NormalizeCharMap.Builder builder = new NormalizeCharMap.Builder();
parseRules(wlist, builder);
normMap = builder.build();
if (normMap.map == null) {
normMap = null;
}
}
}
@Override
public Reader create(Reader input) {
return normMap == null ? input : new MappingCharFilter(normMap,input);
}
@Override
public Reader normalize(Reader input) {
return create(input);
}
static Pattern p = Pattern.compile( "\"(.*)\"\\s*=>\\s*\"(.*)\"\\s*$" );
protected void parseRules( List<String> rules, NormalizeCharMap.Builder builder ){
for( String rule : rules ){
Matcher m = p.matcher( rule );
if( !m.find() )
throw new IllegalArgumentException("Invalid Mapping Rule : [" + rule + "], file = " + mapping);
builder.add( parseString( m.group( 1 ) ), parseString( m.group( 2 ) ) );
}
}
char[] out = new char[256];
protected String parseString( String s ){
int readPos = 0;
int len = s.length();
int writePos = 0;
while( readPos < len ){
char c = s.charAt( readPos++ );
if( c == '\\' ){
if( readPos >= len )
throw new IllegalArgumentException("Invalid escaped char in [" + s + "]");
c = s.charAt( readPos++ );
switch( c ) {
case '\\' : c = '\\'; break;
case '"' : c = '"'; break;
case 'n' : c = '\n'; break;
case 't' : c = '\t'; break;
case 'r' : c = '\r'; break;
case 'b' : c = '\b'; break;
case 'f' : c = '\f'; break;
case 'u' :
if( readPos + 3 >= len )
throw new IllegalArgumentException("Invalid escaped char in [" + s + "]");
c = (char)Integer.parseInt( s.substring( readPos, readPos + 4 ), 16 );
readPos += 4;
break;
}
}
out[writePos++] = c;
}
return new String( out, 0, writePos );
}
}