FileParser.java

/*
 * Copyright 2023 Terminal Utils Authors
 *
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied. See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package net.morimekta.terminal.args.parser;

import net.morimekta.terminal.args.ArgException;
import net.morimekta.terminal.args.ValueParser;

import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;

/**
 * A converter to file instances, with validator & error message.
 */
public class FileParser implements ValueParser<Path> {
    @Override
    public Path parse(String s) {
        Path result = Paths.get(s);
        try {
            if (!Files.exists(result)) {
                throw new ArgException("No such file %s", s);
            }
            var real = result.toAbsolutePath().toRealPath();
            if (!Files.isRegularFile(real)) {
                throw new ArgException("%s is not a file", s);
            }
        } catch (IOException e) {
            throw new ArgException("%s is not a valid path", s, e);
        }
        return result;
    }
}