com.twitter.hbc.common.IOUtils Maven / Gradle / Ivy
/**
* Copyright 2013 Twitter, Inc.
* 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.twitter.hbc.common;
import java.io.IOException;
import java.io.Reader;
public class IOUtils {
/**
* Reads enough chars from the reader to fill the remainder of the buffer (reads length - offset chars).
* @throws IOException if an I/O error occurs, or if the stream ends before filling the entire buffer.
*/
public static void readFully(Reader reader, char[] buffer, int offset) throws IOException {
int originalOffset = offset;
int expected = buffer.length - offset;
while (offset < buffer.length) {
int numRead = reader.read(buffer, offset, buffer.length - offset);
if (numRead < 0) {
throw new IOException(
String.format("Reached end of stream earlier than expected. Expected to read %d bytes. Actual: %d",
expected, offset - originalOffset));
}
offset += numRead;
}
}
}