/*
* Copyright (c) 2011 Google Inc.
*
* All rights reserved. This program and the accompanying materials are made available under the terms of the Eclipse
* Public License v1.0 which accompanies this distribution, and is available at
*
* http://www.eclipse.org/legal/epl-v10.html
*/
package com.google.eclipse.protobuf.conversion;
import static org.eclipse.xtext.util.Strings.convertToJavaString;
import static com.google.eclipse.protobuf.util.Strings.removeLineBreaks;
import static com.google.eclipse.protobuf.util.Strings.unquote;
import org.eclipse.xtext.conversion.ValueConverterException;
import org.eclipse.xtext.conversion.impl.AbstractLexerBasedConverter;
import org.eclipse.xtext.nodemodel.INode;
import com.google.common.base.Function;
/**
* Converts multi-line strings to {@code String}s.
*
* @author alruiz@google.com (Alex Ruiz)
*/
public class STRINGValueConverter extends AbstractLexerBasedConverter<String> {
@Override protected String toEscapedString(String value) {
if (value == null) {
return null;
}
// TODO check if we really need to quote
return '"' + toValue(value) + '"';
}
/**
* Creates a {@code String} from the given input, if the given input represents a multiple-line string.
* @param string the given input.
* @param node the parsed node including hidden parts.
* @return the new {@code String}.
* @throws ValueConverterException if the given input has illegal characters.
*/
@Override public String toValue(String string, INode node) throws ValueConverterException {
if (string == null) {
return null;
}
try {
return toValue(string);
} catch (RuntimeException e) {
throw parsingError(string, node, e);
}
}
private String toValue(String string) {
return removeLineBreaks(string, LineTransformation.INSTANCE);
}
private ValueConverterException parsingError(String string, INode node, Exception cause) {
return new ValueConverterException("Couldn't convert '" + string + "' to String.", node, cause);
}
private static class LineTransformation implements Function<String, String> {
private static final LineTransformation INSTANCE = new LineTransformation();
@Override public String apply(String input) {
return convertToJavaString(unquote(input), true);
}
}
}