// Copyright 2016 The Bazel Authors. All rights reserved.
//
// 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 com.google.devtools.build.lib.util.io;
import java.io.IOException;
/**
* An append-only interface to access to a terminal.
*
* This interface allows to specify a text to be written to the user
* using semantical highlighting (like failure) without any knowledge
* about the nature of the terminal or the position the text is to be
* written to. Callers to this interface should make no assumption
* about how the text is rendered; if the user's terminal does not
* support, e.g., colors, the highlighting might be done by adding
* additional characters.
*
* All interface functions are supposed to return the object itself
* to allow chaining of commands.
*/
public interface AnsiTerminalWriter {
/**
* Write some text to the user
*/
AnsiTerminalWriter append(String text) throws IOException;
/**
* Start a new line in the way appropriate for the given terminal
*/
AnsiTerminalWriter newline() throws IOException;
/**
* Tell the terminal that the following text will be a positive
* status message.
*/
AnsiTerminalWriter okStatus() throws IOException;
/**
* Tell the terminal that the following text will be an error-reporting
* status message.
*/
AnsiTerminalWriter failStatus() throws IOException;
/**
* Tell the terminal that the following text will be normal text, not
* indicating a status or similar.
*/
AnsiTerminalWriter normal() throws IOException;
}