/**
* 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 org.apache.kafka.common.utils;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.UnsupportedEncodingException;
import java.nio.ByteBuffer;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import org.apache.kafka.common.KafkaException;
public class Utils {
private static final Pattern HOST_PORT_PATTERN = Pattern.compile("\\[?(.+?)\\]?:(\\d+)");
public static String NL = System.getProperty("line.separator");
/**
* Turn the given UTF8 byte array into a string
*
* @param bytes The byte array
* @return The string
*/
public static String utf8(byte[] bytes) {
try {
return new String(bytes, "UTF8");
} catch (UnsupportedEncodingException e) {
throw new RuntimeException("This shouldn't happen.", e);
}
}
/**
* Turn a string into a utf8 byte[]
*
* @param string The string
* @return The byte[]
*/
public static byte[] utf8(String string) {
try {
return string.getBytes("UTF8");
} catch (UnsupportedEncodingException e) {
throw new RuntimeException("This shouldn't happen.", e);
}
}
/**
* Read an unsigned integer from the current position in the buffer, incrementing the position by 4 bytes
*
* @param buffer The buffer to read from
* @return The integer read, as a long to avoid signedness
*/
public static long readUnsignedInt(ByteBuffer buffer) {
return buffer.getInt() & 0xffffffffL;
}
/**
* Read an unsigned integer from the given position without modifying the buffers position
*
* @param buffer the buffer to read from
* @param index the index from which to read the integer
* @return The integer read, as a long to avoid signedness
*/
public static long readUnsignedInt(ByteBuffer buffer, int index) {
return buffer.getInt(index) & 0xffffffffL;
}
/**
* Read an unsigned integer stored in little-endian format from the {@link InputStream}.
*
* @param in The stream to read from
* @return The integer read (MUST BE TREATED WITH SPECIAL CARE TO AVOID SIGNEDNESS)
*/
public static int readUnsignedIntLE(InputStream in) throws IOException {
return (in.read() << 8*0)
| (in.read() << 8*1)
| (in.read() << 8*2)
| (in.read() << 8*3);
}
/**
* Read an unsigned integer stored in little-endian format from a byte array
* at a given offset.
*
* @param buffer The byte array to read from
* @param offset The position in buffer to read from
* @return The integer read (MUST BE TREATED WITH SPECIAL CARE TO AVOID SIGNEDNESS)
*/
public static int readUnsignedIntLE(byte[] buffer, int offset) {
return (buffer[offset++] << 8*0)
| (buffer[offset++] << 8*1)
| (buffer[offset++] << 8*2)
| (buffer[offset] << 8*3);
}
/**
* Write the given long value as a 4 byte unsigned integer. Overflow is ignored.
*
* @param buffer The buffer to write to
* @param value The value to write
*/
public static void writetUnsignedInt(ByteBuffer buffer, long value) {
buffer.putInt((int) (value & 0xffffffffL));
}
/**
* Write the given long value as a 4 byte unsigned integer. Overflow is ignored.
*
* @param buffer The buffer to write to
* @param index The position in the buffer at which to begin writing
* @param value The value to write
*/
public static void writeUnsignedInt(ByteBuffer buffer, int index, long value) {
buffer.putInt(index, (int) (value & 0xffffffffL));
}
/**
* Write an unsigned integer in little-endian format to the {@link OutputStream}.
*
* @param out The stream to write to
* @param value The value to write
*/
public static void writeUnsignedIntLE(OutputStream out, int value) throws IOException {
out.write(value >>> 8*0);
out.write(value >>> 8*1);
out.write(value >>> 8*2);
out.write(value >>> 8*3);
}
/**
* Write an unsigned integer in little-endian format to a byte array
* at a given offset.
*
* @param buffer The byte array to write to
* @param offset The position in buffer to write to
* @param value The value to write
*/
public static void writeUnsignedIntLE(byte[] buffer, int offset, int value) {
buffer[offset++] = (byte) (value >>> 8*0);
buffer[offset++] = (byte) (value >>> 8*1);
buffer[offset++] = (byte) (value >>> 8*2);
buffer[offset] = (byte) (value >>> 8*3);
}
/**
* Get the absolute value of the given number. If the number is Int.MinValue return 0. This is different from
* java.lang.Math.abs or scala.math.abs in that they return Int.MinValue (!).
*/
public static int abs(int n) {
return n & 0x7fffffff;
}
/**
* Get the length for UTF8-encoding a string without encoding it first
*
* @param s The string to calculate the length for
* @return The length when serialized
*/
public static int utf8Length(CharSequence s) {
int count = 0;
for (int i = 0, len = s.length(); i < len; i++) {
char ch = s.charAt(i);
if (ch <= 0x7F) {
count++;
} else if (ch <= 0x7FF) {
count += 2;
} else if (Character.isHighSurrogate(ch)) {
count += 4;
++i;
} else {
count += 3;
}
}
return count;
}
/**
* Read the given byte buffer into a byte array
*/
public static byte[] toArray(ByteBuffer buffer) {
return toArray(buffer, 0, buffer.limit());
}
/**
* Read a byte array from the given offset and size in the buffer
*/
public static byte[] toArray(ByteBuffer buffer, int offset, int size) {
byte[] dest = new byte[size];
if (buffer.hasArray()) {
System.arraycopy(buffer.array(), buffer.arrayOffset() + offset, dest, 0, size);
} else {
int pos = buffer.position();
buffer.get(dest);
buffer.position(pos);
}
return dest;
}
/**
* Check that the parameter t is not null
*
* @param t The object to check
* @return t if it isn't null
* @throws NullPointerException if t is null.
*/
public static <T> T notNull(T t) {
if (t == null)
throw new NullPointerException();
else
return t;
}
/**
* Instantiate the class
*/
public static Object newInstance(Class<?> c) {
try {
return c.newInstance();
} catch (IllegalAccessException e) {
throw new KafkaException("Could not instantiate class " + c.getName(), e);
} catch (InstantiationException e) {
throw new KafkaException("Could not instantiate class " + c.getName() + " Does it have a public no-argument constructor?", e);
}
}
/**
* Generates 32 bit murmur2 hash from byte array
* @param data byte array to hash
* @return 32 bit hash of the given array
*/
public static int murmur2(final byte[] data) {
int length = data.length;
int seed = 0x9747b28c;
// 'm' and 'r' are mixing constants generated offline.
// They're not really 'magic', they just happen to work well.
final int m = 0x5bd1e995;
final int r = 24;
// Initialize the hash to a random value
int h = seed ^ length;
int length4 = length / 4;
for (int i = 0; i < length4; i++) {
final int i4 = i * 4;
int k = (data[i4 + 0] & 0xff) + ((data[i4 + 1] & 0xff) << 8) + ((data[i4 + 2] & 0xff) << 16) + ((data[i4 + 3] & 0xff) << 24);
k *= m;
k ^= k >>> r;
k *= m;
h *= m;
h ^= k;
}
// Handle the last few bytes of the input array
switch (length % 4) {
case 3:
h ^= (data[(length & ~3) + 2] & 0xff) << 16;
case 2:
h ^= (data[(length & ~3) + 1] & 0xff) << 8;
case 1:
h ^= (data[length & ~3] & 0xff);
h *= m;
}
h ^= h >>> 13;
h *= m;
h ^= h >>> 15;
return h;
}
/**
* Extracts the hostname from a "host:port" address string.
* @param address address string to parse
* @return hostname or null if the given address is incorrect
*/
public static String getHost(String address) {
Matcher matcher = HOST_PORT_PATTERN.matcher(address);
return matcher.matches() ? matcher.group(1) : null;
}
/**
* Extracts the port number from a "host:port" address string.
* @param address address string to parse
* @return port number or null if the given address is incorrect
*/
public static Integer getPort(String address) {
Matcher matcher = HOST_PORT_PATTERN.matcher(address);
return matcher.matches() ? Integer.parseInt(matcher.group(2)) : null;
}
/**
* Formats hostname and port number as a "host:port" address string,
* surrounding IPv6 addresses with braces '[', ']'
* @param host hostname
* @param port port number
* @return address string
*/
public static String formatAddress(String host, Integer port) {
return host.contains(":")
? "[" + host + "]:" + port // IPv6
: host + ":" + port;
}
}