com.firefly.utils.io.BufferUtils Maven / Gradle / Ivy
package com.firefly.utils.io;
import java.io.File;
import java.io.FileDescriptor;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.RandomAccessFile;
import java.lang.reflect.Field;
import java.nio.Buffer;
import java.nio.BufferOverflowException;
import java.nio.ByteBuffer;
import java.nio.MappedByteBuffer;
import java.nio.channels.FileChannel;
import java.nio.channels.FileChannel.MapMode;
import java.nio.charset.Charset;
import java.nio.charset.StandardCharsets;
import java.nio.file.StandardOpenOption;
import java.util.Arrays;
import com.firefly.utils.lang.TypeUtils;
/**
* Buffer utility methods.
*
* The standard JVM {@link ByteBuffer} can exist in two modes: In fill mode the
* valid data is between 0 and pos; In flush mode the valid data is between the
* pos and the limit. The various ByteBuffer methods assume a mode and some of
* them will switch or enforce a mode: Allocate and clear set fill mode; flip
* and compact switch modes; read and write assume fill and flush modes. This
* duality can result in confusing code such as:
*
*
*
* buffer.clear();
* channel.write(buffer);
*
*
* Which looks as if it should write no data, but in fact writes the buffer
* worth of garbage.
*
*
* The BufferUtils class provides a set of utilities that operate on the
* convention that ByteBuffers will always be left, passed in an API or returned
* from a method in the flush mode - ie with valid data between the pos and
* limit. This convention is adopted so as to avoid confusion as to what state a
* buffer is in and to avoid excessive copying of data that can result with the
* usage of compress.
*
*
* Thus this class provides alternate implementations of {@link #allocate(int)},
* {@link #allocateDirect(int)} and {@link #clear(ByteBuffer)} that leave the
* buffer in flush mode. Thus the following tests will pass:
*
*
*
* ByteBuffer buffer = BufferUtils.allocate(1024);
* assert (buffer.remaining() == 0);
* BufferUtils.clear(buffer);
* assert (buffer.remaining() == 0);
*
*
* If the BufferUtils methods {@link #fill(ByteBuffer, byte[], int, int)},
* {@link #append(ByteBuffer, byte[], int, int)} or
* {@link #put(ByteBuffer, ByteBuffer)} are used, then the caller does not need
* to explicitly switch the buffer to fill mode. If the caller wishes to use
* other ByteBuffer bases libraries to fill a buffer, then they can use explicit
* calls of #flipToFill(ByteBuffer) and #flipToFlush(ByteBuffer, int) to change
* modes. Note because this convention attempts to avoid the copies of compact,
* the position is not set to zero on each fill cycle and so its value must be
* remembered:
*
*
*
* int pos = BufferUtils.flipToFill(buffer);
* try {
* buffer.put(data);
* } finally {
* flipToFlush(buffer, pos);
* }
*
*
* The flipToFill method will effectively clear the buffer if it is empty and
* will compact the buffer if there is no space.
*
*/
public class BufferUtils {
public static final int TEMP_BUFFER_SIZE = 4096;
static final byte SPACE = 0x20;
static final byte MINUS = '-';
static final byte[] DIGIT = { (byte) '0', (byte) '1', (byte) '2', (byte) '3', (byte) '4', (byte) '5', (byte) '6',
(byte) '7', (byte) '8', (byte) '9', (byte) 'A', (byte) 'B', (byte) 'C', (byte) 'D', (byte) 'E',
(byte) 'F' };
public static final ByteBuffer EMPTY_BUFFER = ByteBuffer.wrap(new byte[0]);
public static final ByteBuffer[] EMPTY_BYTE_BUFFER_ARRAY = new ByteBuffer[0];
/**
* The capacity modulo 1024 is 0
*
* @param capacity
* the buffer size
* @return the buffer size that modulo 1024 is 0
*/
public static int normalizeBufferSize(int capacity) {
int q = capacity >>> 10;
int r = capacity & 1023;
if (r != 0) {
q++;
}
return q << 10;
}
/**
* Allocate ByteBuffer in flush mode. The position and limit will both be
* zero, indicating that the buffer is empty and must be flipped before any
* data is put to it.
*
* @param capacity
* capacity of the allocated ByteBuffer
* @return Buffer
*/
public static ByteBuffer allocate(int capacity) {
ByteBuffer buf = ByteBuffer.allocate(capacity);
buf.limit(0);
return buf;
}
/**
* Allocate ByteBuffer in flush mode. The position and limit will both be
* zero, indicating that the buffer is empty and in flush mode.
*
* @param capacity
* capacity of the allocated ByteBuffer
* @return Buffer
*/
public static ByteBuffer allocateDirect(int capacity) {
ByteBuffer buf = ByteBuffer.allocateDirect(capacity);
buf.limit(0);
return buf;
}
/**
* Clear the buffer to be empty in flush mode. The position and limit are
* set to 0;
*
* @param buffer
* The buffer to clear.
*/
public static void clear(ByteBuffer buffer) {
if (buffer != null) {
buffer.position(0);
buffer.limit(0);
}
}
/**
* Clear the buffer to be empty in fill mode. The position is set to 0 and
* the limit is set to the capacity.
*
* @param buffer
* The buffer to clear.
*/
public static void clearToFill(ByteBuffer buffer) {
if (buffer != null) {
buffer.position(0);
buffer.limit(buffer.capacity());
}
}
/**
* Flip the buffer to fill mode. The position is set to the first unused
* position in the buffer (the old limit) and the limit is set to the
* capacity. If the buffer is empty, then this call is effectively
* {@link #clearToFill(ByteBuffer)}. If there is no unused space to fill, a
* {@link ByteBuffer#compact()} is done to attempt to create space.
*
* This method is used as a replacement to {@link ByteBuffer#compact()}.
*
* @param buffer
* The buffer to flip
* @return The position of the valid data before the flipped position. This
* value should be passed to a subsequent call to
* {@link #flipToFlush(ByteBuffer, int)}
*/
public static int flipToFill(ByteBuffer buffer) {
int position = buffer.position();
int limit = buffer.limit();
if (position == limit) {
buffer.position(0);
buffer.limit(buffer.capacity());
return 0;
}
int capacity = buffer.capacity();
if (limit == capacity) {
buffer.compact();
return 0;
}
buffer.position(limit);
buffer.limit(capacity);
return position;
}
/**
* Flip the buffer to Flush mode. The limit is set to the first unused
* byte(the old position) and the position is set to the passed position.
*
* This method is used as a replacement of {@link Buffer#flip()}.
*
* @param buffer
* the buffer to be flipped
* @param position
* The position of valid data to flip to. This should be the
* return value of the previous call to
* {@link #flipToFill(ByteBuffer)}
*/
public static void flipToFlush(ByteBuffer buffer, int position) {
buffer.limit(buffer.position());
buffer.position(position);
}
/**
* Convert a ByteBuffer to a byte array.
*
* @param buffer
* The buffer to convert in flush mode. The buffer is not
* altered.
* @return An array of bytes duplicated from the buffer.
*/
public static byte[] toArray(ByteBuffer buffer) {
if (buffer.hasArray()) {
byte[] array = buffer.array();
int from = buffer.arrayOffset() + buffer.position();
return Arrays.copyOfRange(array, from, from + buffer.remaining());
} else {
byte[] to = new byte[buffer.remaining()];
buffer.slice().get(to);
return to;
}
}
/**
* Check for an empty or null buffer.
*
* @param buf
* the buffer to check
* @return true if the buffer is null or empty.
*/
public static boolean isEmpty(ByteBuffer buf) {
return buf == null || buf.remaining() == 0;
}
/**
* Check for a non null and non empty buffer.
*
* @param buf
* the buffer to check
* @return true if the buffer is not null and not empty.
*/
public static boolean hasContent(ByteBuffer buf) {
return buf != null && buf.remaining() > 0;
}
/**
* Check for a non null and full buffer.
*
* @param buf
* the buffer to check
* @return true if the buffer is not null and the limit equals the capacity.
*/
public static boolean isFull(ByteBuffer buf) {
return buf != null && buf.limit() == buf.capacity();
}
/**
* Get remaining from null checked buffer
*
* @param buffer
* The buffer to get the remaining from, in flush mode.
* @return 0 if the buffer is null, else the bytes remaining in the buffer.
*/
public static int length(ByteBuffer buffer) {
return buffer == null ? 0 : buffer.remaining();
}
/**
* Get the space from the limit to the capacity
*
* @param buffer
* the buffer to get the space from
* @return space
*/
public static int space(ByteBuffer buffer) {
if (buffer == null)
return 0;
return buffer.capacity() - buffer.limit();
}
/**
* Compact the buffer
*
* @param buffer
* the buffer to compact
* @return true if the compact made a full buffer have space
*/
public static boolean compact(ByteBuffer buffer) {
if (buffer.position() == 0)
return false;
boolean full = buffer.limit() == buffer.capacity();
buffer.compact().flip();
return full && buffer.limit() < buffer.capacity();
}
/**
* Put data from one buffer into another, avoiding over/under flows
*
* @param from
* Buffer to take bytes from in flush mode
* @param to
* Buffer to put bytes to in fill mode.
* @return number of bytes moved
*/
public static int put(ByteBuffer from, ByteBuffer to) {
int put;
int remaining = from.remaining();
if (remaining > 0) {
if (remaining <= to.remaining()) {
to.put(from);
put = remaining;
from.position(from.limit());
} else if (from.hasArray()) {
put = to.remaining();
to.put(from.array(), from.arrayOffset() + from.position(), put);
from.position(from.position() + put);
} else {
put = to.remaining();
ByteBuffer slice = from.slice();
slice.limit(put);
to.put(slice);
from.position(from.position() + put);
}
} else
put = 0;
return put;
}
/**
* Put data from one buffer into another, avoiding over/under flows
*
* @param from
* Buffer to take bytes from in flush mode
* @param to
* Buffer to put bytes to in flush mode. The buffer is flipToFill
* before the put and flipToFlush after.
* @return number of bytes moved
* @deprecated use {@link #append(ByteBuffer, ByteBuffer)}
*/
public static int flipPutFlip(ByteBuffer from, ByteBuffer to) {
return append(to, from);
}
/**
* Append bytes to a buffer.
*
* @param to
* Buffer is flush mode
* @param b
* bytes to append
* @param off
* offset into byte
* @param len
* length to append
* @throws BufferOverflowException
* if unable to append buffer due to space limits
*/
public static void append(ByteBuffer to, byte[] b, int off, int len) throws BufferOverflowException {
int pos = flipToFill(to);
try {
to.put(b, off, len);
} finally {
flipToFlush(to, pos);
}
}
/**
* Appends a byte to a buffer
*
* @param to
* Buffer is flush mode
* @param b
* byte to append
*/
public static void append(ByteBuffer to, byte b) {
int pos = flipToFill(to);
try {
to.put(b);
} finally {
flipToFlush(to, pos);
}
}
/**
* Appends a buffer to a buffer
*
* @param to
* Buffer is flush mode
* @param b
* buffer to append
* @return The position of the valid data before the flipped position.
*/
public static int append(ByteBuffer to, ByteBuffer b) {
int pos = flipToFill(to);
try {
return put(b, to);
} finally {
flipToFlush(to, pos);
}
}
/**
* Like append, but does not throw {@link BufferOverflowException}
*
* @param to
* Buffer is flush mode
* @param b
* bytes to fill
* @param off
* offset into byte
* @param len
* length to fill
* @return The position of the valid data before the flipped position.
*/
public static int fill(ByteBuffer to, byte[] b, int off, int len) {
int pos = flipToFill(to);
try {
int remaining = to.remaining();
int take = remaining < len ? remaining : len;
to.put(b, off, take);
return take;
} finally {
flipToFlush(to, pos);
}
}
public static void readFrom(File file, ByteBuffer buffer) throws IOException {
try (RandomAccessFile raf = new RandomAccessFile(file, "r")) {
FileChannel channel = raf.getChannel();
long needed = raf.length();
while (needed > 0 && buffer.hasRemaining())
needed = needed - channel.read(buffer);
}
}
public static void readFrom(InputStream is, int needed, ByteBuffer buffer) throws IOException {
ByteBuffer tmp = allocate(8192);
while (needed > 0 && buffer.hasRemaining()) {
int l = is.read(tmp.array(), 0, 8192);
if (l < 0)
break;
tmp.position(0);
tmp.limit(l);
buffer.put(tmp);
}
}
public static void writeTo(ByteBuffer buffer, OutputStream out) throws IOException {
if (buffer.hasArray()) {
out.write(buffer.array(), buffer.arrayOffset() + buffer.position(), buffer.remaining());
// update buffer position, in way similar to non-array version of
// writeTo
buffer.position(buffer.position() + buffer.remaining());
} else {
byte[] bytes = new byte[TEMP_BUFFER_SIZE];
while (buffer.hasRemaining()) {
int byteCountToWrite = Math.min(buffer.remaining(), TEMP_BUFFER_SIZE);
buffer.get(bytes, 0, byteCountToWrite);
out.write(bytes, 0, byteCountToWrite);
}
}
}
/**
* Convert the buffer to an ISO-8859-1 String
*
* @param buffer
* The buffer to convert in flush mode. The buffer is unchanged
* @return The buffer as a string.
*/
public static String toString(ByteBuffer buffer) {
return toString(buffer, StandardCharsets.ISO_8859_1);
}
/**
* Convert the buffer to an UTF-8 String
*
* @param buffer
* The buffer to convert in flush mode. The buffer is unchanged
* @return The buffer as a string.
*/
public static String toUTF8String(ByteBuffer buffer) {
return toString(buffer, StandardCharsets.UTF_8);
}
/**
* Convert the buffer to an ISO-8859-1 String
*
* @param buffer
* The buffer to convert in flush mode. The buffer is unchanged
* @param charset
* The {@link Charset} to use to convert the bytes
* @return The buffer as a string.
*/
public static String toString(ByteBuffer buffer, Charset charset) {
if (buffer == null)
return null;
byte[] array = buffer.hasArray() ? buffer.array() : null;
if (array == null) {
byte[] to = new byte[buffer.remaining()];
buffer.slice().get(to);
return new String(to, 0, to.length, charset);
}
return new String(array, buffer.arrayOffset() + buffer.position(), buffer.remaining(), charset);
}
/**
* Convert a partial buffer to a String.
*
* @param buffer
* the buffer to convert
* @param position
* The position in the buffer to start the string from
* @param length
* The length of the buffer
* @param charset
* The {@link Charset} to use to convert the bytes
* @return The buffer as a string.
*/
public static String toString(ByteBuffer buffer, int position, int length, Charset charset) {
if (buffer == null)
return null;
byte[] array = buffer.hasArray() ? buffer.array() : null;
if (array == null) {
ByteBuffer ro = buffer.asReadOnlyBuffer();
ro.position(position);
ro.limit(position + length);
byte[] to = new byte[length];
ro.get(to);
return new String(to, 0, to.length, charset);
}
return new String(array, buffer.arrayOffset() + position, length, charset);
}
/**
* Convert buffer to an integer. Parses up to the first non-numeric
* character. If no number is found an IllegalArgumentException is thrown
*
* @param buffer
* A buffer containing an integer in flush mode. The position is
* not changed.
* @return an int
*/
public static int toInt(ByteBuffer buffer) {
return toInt(buffer, buffer.position(), buffer.remaining());
}
/**
* Convert buffer to an integer. Parses up to the first non-numeric
* character. If no number is found an IllegalArgumentException is thrown
*
* @param buffer
* A buffer containing an integer in flush mode. The position is
* not changed.
* @param position
* the position in the buffer to start reading from
* @param length
* the length of the buffer to use for conversion
* @return an int of the buffer bytes
*/
public static int toInt(ByteBuffer buffer, int position, int length) {
int val = 0;
boolean started = false;
boolean minus = false;
int limit = position + length;
if (length <= 0)
throw new NumberFormatException(toString(buffer, position, length, StandardCharsets.UTF_8));
for (int i = position; i < limit; i++) {
byte b = buffer.get(i);
if (b <= SPACE) {
if (started)
break;
} else if (b >= '0' && b <= '9') {
val = val * 10 + (b - '0');
started = true;
} else if (b == MINUS && !started) {
minus = true;
} else
break;
}
if (started)
return minus ? (-val) : val;
throw new NumberFormatException(toString(buffer));
}
/**
* Convert buffer to an integer. Parses up to the first non-numeric
* character. If no number is found an IllegalArgumentException is thrown
*
* @param buffer
* A buffer containing an integer in flush mode. The position is
* updated.
* @return an int
*/
public static int takeInt(ByteBuffer buffer) {
int val = 0;
boolean started = false;
boolean minus = false;
int i;
for (i = buffer.position(); i < buffer.limit(); i++) {
byte b = buffer.get(i);
if (b <= SPACE) {
if (started)
break;
} else if (b >= '0' && b <= '9') {
val = val * 10 + (b - '0');
started = true;
} else if (b == MINUS && !started) {
minus = true;
} else
break;
}
if (started) {
buffer.position(i);
return minus ? (-val) : val;
}
throw new NumberFormatException(toString(buffer));
}
/**
* Convert buffer to an long. Parses up to the first non-numeric character.
* If no number is found an IllegalArgumentException is thrown
*
* @param buffer
* A buffer containing an integer in flush mode. The position is
* not changed.
* @return an int
*/
public static long toLong(ByteBuffer buffer) {
long val = 0;
boolean started = false;
boolean minus = false;
for (int i = buffer.position(); i < buffer.limit(); i++) {
byte b = buffer.get(i);
if (b <= SPACE) {
if (started)
break;
} else if (b >= '0' && b <= '9') {
val = val * 10L + (b - '0');
started = true;
} else if (b == MINUS && !started) {
minus = true;
} else
break;
}
if (started)
return minus ? (-val) : val;
throw new NumberFormatException(toString(buffer));
}
public static void putHexInt(ByteBuffer buffer, int n) {
if (n < 0) {
buffer.put((byte) '-');
if (n == Integer.MIN_VALUE) {
buffer.put((byte) (0x7f & '8'));
buffer.put((byte) (0x7f & '0'));
buffer.put((byte) (0x7f & '0'));
buffer.put((byte) (0x7f & '0'));
buffer.put((byte) (0x7f & '0'));
buffer.put((byte) (0x7f & '0'));
buffer.put((byte) (0x7f & '0'));
buffer.put((byte) (0x7f & '0'));
return;
}
n = -n;
}
if (n < 0x10) {
buffer.put(DIGIT[n]);
} else {
boolean started = false;
// This assumes constant time int arithmatic
for (int hexDivisor : hexDivisors) {
if (n < hexDivisor) {
if (started)
buffer.put((byte) '0');
continue;
}
started = true;
int d = n / hexDivisor;
buffer.put(DIGIT[d]);
n = n - d * hexDivisor;
}
}
}
public static void putDecInt(ByteBuffer buffer, int n) {
if (n < 0) {
buffer.put((byte) '-');
if (n == Integer.MIN_VALUE) {
buffer.put((byte) '2');
n = 147483648;
} else
n = -n;
}
if (n < 10) {
buffer.put(DIGIT[n]);
} else {
boolean started = false;
// This assumes constant time int arithmatic
for (int decDivisor : decDivisors) {
if (n < decDivisor) {
if (started)
buffer.put((byte) '0');
continue;
}
started = true;
int d = n / decDivisor;
buffer.put(DIGIT[d]);
n = n - d * decDivisor;
}
}
}
public static void putDecLong(ByteBuffer buffer, long n) {
if (n < 0) {
buffer.put((byte) '-');
if (n == Long.MIN_VALUE) {
buffer.put((byte) '9');
n = 223372036854775808L;
} else
n = -n;
}
if (n < 10) {
buffer.put(DIGIT[(int) n]);
} else {
boolean started = false;
// This assumes constant time int arithmatic
for (long aDecDivisorsL : decDivisorsL) {
if (n < aDecDivisorsL) {
if (started)
buffer.put((byte) '0');
continue;
}
started = true;
long d = n / aDecDivisorsL;
buffer.put(DIGIT[(int) d]);
n = n - d * aDecDivisorsL;
}
}
}
public static ByteBuffer toBuffer(int value) {
ByteBuffer buf = ByteBuffer.allocate(32);
putDecInt(buf, value);
return buf;
}
public static ByteBuffer toBuffer(long value) {
ByteBuffer buf = ByteBuffer.allocate(32);
putDecLong(buf, value);
return buf;
}
public static ByteBuffer toBuffer(String s) {
return toBuffer(s, StandardCharsets.ISO_8859_1);
}
public static ByteBuffer toBuffer(String s, Charset charset) {
if (s == null)
return EMPTY_BUFFER;
return toBuffer(s.getBytes(charset));
}
/**
* Create a new ByteBuffer using provided byte array.
*
* @param array
* the byte array to back buffer with.
* @return ByteBuffer with provided byte array, in flush mode
*/
public static ByteBuffer toBuffer(byte[] array) {
if (array == null)
return EMPTY_BUFFER;
return toBuffer(array, 0, array.length);
}
/**
* Create a new ByteBuffer using the provided byte array.
*
* @param array
* the byte array to use.
* @param offset
* the offset within the byte array to use from
* @param length
* the length in bytes of the array to use
* @return ByteBuffer with provided byte array, in flush mode
*/
public static ByteBuffer toBuffer(byte array[], int offset, int length) {
if (array == null)
return EMPTY_BUFFER;
return ByteBuffer.wrap(array, offset, length);
}
public static ByteBuffer toDirectBuffer(String s) {
return toDirectBuffer(s, StandardCharsets.ISO_8859_1);
}
public static ByteBuffer toDirectBuffer(String s, Charset charset) {
if (s == null)
return EMPTY_BUFFER;
byte[] bytes = s.getBytes(charset);
ByteBuffer buf = ByteBuffer.allocateDirect(bytes.length);
buf.put(bytes);
buf.flip();
return buf;
}
public static ByteBuffer toMappedBuffer(File file) throws IOException {
try (FileChannel channel = FileChannel.open(file.toPath(), StandardOpenOption.READ)) {
return channel.map(MapMode.READ_ONLY, 0, file.length());
}
}
static final Field fdMappedByteBuffer;
static {
Field fd = null;
try {
fd = MappedByteBuffer.class.getDeclaredField("fd");
fd.setAccessible(true);
} catch (Exception e) {
}
fdMappedByteBuffer = fd;
}
public static boolean isMappedBuffer(ByteBuffer buffer) {
if (!(buffer instanceof MappedByteBuffer))
return false;
MappedByteBuffer mapped = (MappedByteBuffer) buffer;
if (fdMappedByteBuffer != null) {
try {
if (fdMappedByteBuffer.get(mapped) instanceof FileDescriptor)
return true;
} catch (Exception e) {
}
}
return false;
}
public static String toSummaryString(ByteBuffer buffer) {
if (buffer == null)
return "null";
StringBuilder buf = new StringBuilder();
buf.append("[p=");
buf.append(buffer.position());
buf.append(",l=");
buf.append(buffer.limit());
buf.append(",c=");
buf.append(buffer.capacity());
buf.append(",r=");
buf.append(buffer.remaining());
buf.append("]");
return buf.toString();
}
public static String toDetailString(ByteBuffer[] buffer) {
StringBuilder builder = new StringBuilder();
builder.append('[');
for (int i = 0; i < buffer.length; i++) {
if (i > 0)
builder.append(',');
builder.append(toDetailString(buffer[i]));
}
builder.append(']');
return builder.toString();
}
/**
* Convert Buffer to string ID independent of content
*/
private static void idString(ByteBuffer buffer, StringBuilder out) {
out.append(buffer.getClass().getSimpleName());
out.append("@");
if (buffer.hasArray() && buffer.arrayOffset() == 4) {
out.append('T');
byte[] array = buffer.array();
TypeUtils.toHex(array[0], out);
TypeUtils.toHex(array[1], out);
TypeUtils.toHex(array[2], out);
TypeUtils.toHex(array[3], out);
} else
out.append(Integer.toHexString(System.identityHashCode(buffer)));
}
/**
* Convert Buffer to string ID independent of content
*
* @param buffer
* the buffet to generate a string ID from
* @return A string showing the buffer ID
*/
public static String toIDString(ByteBuffer buffer) {
StringBuilder buf = new StringBuilder();
idString(buffer, buf);
return buf.toString();
}
/**
* Convert Buffer to a detail debug string of pointers and content
*
* @param buffer
* the buffer to generate a detail string from
* @return A string showing the pointers and content of the buffer
*/
public static String toDetailString(ByteBuffer buffer) {
if (buffer == null)
return "null";
StringBuilder buf = new StringBuilder();
idString(buffer, buf);
buf.append("[p=");
buf.append(buffer.position());
buf.append(",l=");
buf.append(buffer.limit());
buf.append(",c=");
buf.append(buffer.capacity());
buf.append(",r=");
buf.append(buffer.remaining());
buf.append("]={");
appendDebugString(buf, buffer);
buf.append("}");
return buf.toString();
}
private static void appendDebugString(StringBuilder buf, ByteBuffer buffer) {
try {
for (int i = 0; i < buffer.position(); i++) {
appendContentChar(buf, buffer.get(i));
if (i == 16 && buffer.position() > 32) {
buf.append("...");
i = buffer.position() - 16;
}
}
buf.append("<<<");
for (int i = buffer.position(); i < buffer.limit(); i++) {
appendContentChar(buf, buffer.get(i));
if (i == buffer.position() + 16 && buffer.limit() > buffer.position() + 32) {
buf.append("...");
i = buffer.limit() - 16;
}
}
buf.append(">>>");
int limit = buffer.limit();
buffer.limit(buffer.capacity());
for (int i = limit; i < buffer.capacity(); i++) {
appendContentChar(buf, buffer.get(i));
if (i == limit + 16 && buffer.capacity() > limit + 32) {
buf.append("...");
i = buffer.capacity() - 16;
}
}
buffer.limit(limit);
} catch (Throwable x) {
buf.append("!!concurrent mod!!");
}
}
private static void appendContentChar(StringBuilder buf, byte b) {
if (b == '\\')
buf.append("\\\\");
else if (b >= ' ')
buf.append((char) b);
else if (b == '\r')
buf.append("\\r");
else if (b == '\n')
buf.append("\\n");
else if (b == '\t')
buf.append("\\t");
else
buf.append("\\x").append(TypeUtils.toHexString(b));
}
/**
* Convert buffer to a Hex Summary String.
*
* @param buffer
* the buffer to generate a hex byte summary from
* @return A string showing the escaped content of the buffer around the
* position and limit (marked with <<< and >>>)
*/
public static String toHexSummary(ByteBuffer buffer) {
if (buffer == null)
return "null";
StringBuilder buf = new StringBuilder();
buf.append("b[").append(buffer.remaining()).append("]=");
for (int i = buffer.position(); i < buffer.limit(); i++) {
TypeUtils.toHex(buffer.get(i), buf);
if (i == buffer.position() + 24 && buffer.limit() > buffer.position() + 32) {
buf.append("...");
i = buffer.limit() - 8;
}
}
return buf.toString();
}
private final static int[] decDivisors = { 1000000000, 100000000, 10000000, 1000000, 100000, 10000, 1000, 100, 10,
1 };
private final static int[] hexDivisors = { 0x10000000, 0x1000000, 0x100000, 0x10000, 0x1000, 0x100, 0x10, 0x1 };
private final static long[] decDivisorsL = { 1000000000000000000L, 100000000000000000L, 10000000000000000L,
1000000000000000L, 100000000000000L, 10000000000000L, 1000000000000L, 100000000000L, 10000000000L,
1000000000L, 100000000L, 10000000L, 1000000L, 100000L, 10000L, 1000L, 100L, 10L, 1L };
public static void putCRLF(ByteBuffer buffer) {
buffer.put((byte) 13);
buffer.put((byte) 10);
}
public static boolean isPrefix(ByteBuffer prefix, ByteBuffer buffer) {
if (prefix.remaining() > buffer.remaining())
return false;
int bi = buffer.position();
for (int i = prefix.position(); i < prefix.limit(); i++)
if (prefix.get(i) != buffer.get(bi++))
return false;
return true;
}
public static ByteBuffer ensureCapacity(ByteBuffer buffer, int capacity) {
if (buffer == null)
return allocate(capacity);
if (buffer.capacity() >= capacity)
return buffer;
if (buffer.hasArray())
return ByteBuffer.wrap(
Arrays.copyOfRange(buffer.array(), buffer.arrayOffset(), buffer.arrayOffset() + capacity),
buffer.position(), buffer.remaining());
throw new UnsupportedOperationException();
}
}