io.trino.cli.TerminalUtils Maven / Gradle / Ivy

Show more of this group Show more artifacts with this name
Show all versions of trino-cli Show documentation
Trino - CLI
There is a newer version: 458
/*
 * Licensed 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 io.trino.cli;

import org.jline.terminal.Terminal;
import org.jline.terminal.TerminalBuilder;

import java.io.IOException;
import java.io.UncheckedIOException;
import java.nio.charset.Charset;
import java.util.concurrent.atomic.AtomicBoolean;

import static com.google.common.base.Preconditions.checkState;

public class TerminalUtils
{
    private static final Terminal TERMINAL_INSTANCE = createTerminal();
    private static final AtomicBoolean closed = new AtomicBoolean(false);

    private TerminalUtils() {}

    public static Terminal getTerminal()
    {
        checkState(!closed.get(), "Terminal is already closed");
        return TERMINAL_INSTANCE;
    }

    private static Terminal createTerminal()
    {
        try {
            return TerminalBuilder.builder()
                    .name("Trino")
                    .build();
        }
        catch (IOException e) {
            throw new UncheckedIOException(e);
        }
    }

    public static boolean isRealTerminal(Terminal terminal)
    {
        return !Terminal.TYPE_DUMB.equals(terminal.getType()) &&
                !Terminal.TYPE_DUMB_COLOR.equals(terminal.getType());
    }

    public static boolean isRealTerminal()
    {
        return isRealTerminal(getTerminal());
    }

    public static int terminalWidth()
    {
        return getTerminal().getWidth();
    }

    public static Charset terminalEncoding()
    {
        return getTerminal().encoding();
    }

    public static void closeTerminal()
    {
        Terminal terminal = getTerminal();

        try {
            if (closed.compareAndSet(false, true)) {
                terminal.close();
            }
        }
        catch (IOException e) {
            throw new UncheckedIOException(e);
        }
    }
}