package org.yaac.server.egql;
import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.base.Strings.isNullOrEmpty;
import static com.google.common.collect.Lists.newArrayList;
import java.util.List;
import org.antlr.runtime.ANTLRStringStream;
import org.antlr.runtime.CharStream;
import org.antlr.runtime.CommonTokenStream;
import org.antlr.runtime.RecognitionException;
import org.antlr.runtime.TokenStream;
import org.yaac.server.egql.antlr.EGQLLexer;
import org.yaac.server.egql.antlr.EGQLParser;
import com.google.common.base.Splitter;
/**
* @author Max Zhu (thebbsky@gmail.com)
*
*/
public class EGQLUtil {
/**
* @param inputStr
* @return
* @throws RecognitionException
*/
public static EGQLParser parser(String inputStr) {
checkArgument(!isNullOrEmpty(inputStr));
CharStream input = new ANTLRStringStream(inputStr);
EGQLLexer lexer = new EGQLLexer(input);
TokenStream tokens = new CommonTokenStream(lexer);
return new EGQLParser(tokens);
}
/**
* @param input
* @return
*/
public static EntityProperty parseEntityProperty(String input) {
checkArgument(!isNullOrEmpty(input));
if (input.contains(".")) {
List<String> inputs = newArrayList(Splitter.on('.').split(input));
return new EntityProperty(inputs.get(0), inputs.get(1));
} else {
return new EntityProperty(null, input);
}
}
}