/*
* JBoss, Home of Professional Open Source.
* Copyright 2013 Red Hat, Inc., and individual contributors
* as indicated by the @author tags.
*
* 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 org.jboss.jandex;
import java.io.
DataInputStream;
import java.io.
IOException;
import java.io.
InputStream;
/**
* An input stream that reads integers that were packed by
* {@link PackedDataOutputStream}
*
* <p>
* <b>Thread-Safety</b>
* </p>
* This class is not thread-safe can <b>not<b> be shared between threads.
*
* @author Jason T. Greene
*/
class
PackedDataInputStream extends
DataInputStream {
static final int
MAX_1BYTE = 0x7F;
public
PackedDataInputStream(
InputStream in) {
super(
in);
}
/**
* Reads a packed unsigned integer. Every byte uses the first bit as a control bit to
* signal when there are additional bytes to be read. The remaining seven bits are data.
* Depending on the size of the number one to five bytes may be read.
*
* @return the unpacked integer
*
* @throws IOException
*/
public int
readPackedU32() throws
IOException {
byte
b;
int
i = 0;
do {
b =
readByte();
i = (
i << 7) | (
b &
MAX_1BYTE);
} while ((
b & 0x80) == 0x80);
return
i;
}
}