LongObjectId.java
/*
* Copyright (C) 2015, Matthias Sohn <matthias.sohn@sap.com> and others
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Distribution License v. 1.0 which is available at
* https://www.eclipse.org/org/documents/edl-v10.php.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
package org.eclipse.jgit.lfs.lib;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import org.eclipse.jgit.lfs.errors.InvalidLongObjectIdException;
import org.eclipse.jgit.util.NB;
import org.eclipse.jgit.util.RawParseUtils;
/**
* A SHA-256 abstraction.
*
* Ported to SHA-256 from {@link org.eclipse.jgit.lib.ObjectId}
*
* @since 4.3
*/
public class LongObjectId extends AnyLongObjectId implements Serializable {
private static final long serialVersionUID = 1L;
private static final LongObjectId ZEROID;
private static final String ZEROID_STR;
static {
ZEROID = new LongObjectId(0L, 0L, 0L, 0L);
ZEROID_STR = ZEROID.name();
}
/**
* Get the special all-zero LongObjectId.
*
* @return the all-zero LongObjectId, often used to stand-in for no object.
*/
public static final LongObjectId zeroId() {
return ZEROID;
}
/**
* Test a string of characters to verify that it can be interpreted as
* LongObjectId.
* <p>
* If true the string can be parsed with {@link #fromString(String)}.
*
* @param id
* the string to test.
* @return true if the string can converted into an LongObjectId.
*/
public static final boolean isId(String id) {
if (id.length() != Constants.LONG_OBJECT_ID_STRING_LENGTH)
return false;
try {
for (int i = 0; i < Constants.LONG_OBJECT_ID_STRING_LENGTH; i++) {
RawParseUtils.parseHexInt4((byte) id.charAt(i));
}
return true;
} catch (ArrayIndexOutOfBoundsException e) {
return false;
}
}
/**
* Convert a LongObjectId into a hex string representation.
*
* @param i
* the id to convert. May be null.
* @return the hex string conversion of this id's content.
*/
public static final String toString(LongObjectId i) {
return i != null ? i.name() : ZEROID_STR;
}
/**
* Compare two object identifier byte sequences for equality.
*
* @param firstBuffer
* the first buffer to compare against. Must have at least 32
* bytes from position fi through the end of the buffer.
* @param fi
* first offset within firstBuffer to begin testing.
* @param secondBuffer
* the second buffer to compare against. Must have at least 32
* bytes from position si through the end of the buffer.
* @param si
* first offset within secondBuffer to begin testing.
* @return true if the two identifiers are the same.
*/
public static boolean equals(final byte[] firstBuffer, final int fi,
final byte[] secondBuffer, final int si) {
return firstBuffer[fi] == secondBuffer[si]
&& firstBuffer[fi + 1] == secondBuffer[si + 1]
&& firstBuffer[fi + 2] == secondBuffer[si + 2]
&& firstBuffer[fi + 3] == secondBuffer[si + 3]
&& firstBuffer[fi + 4] == secondBuffer[si + 4]
&& firstBuffer[fi + 5] == secondBuffer[si + 5]
&& firstBuffer[fi + 6] == secondBuffer[si + 6]
&& firstBuffer[fi + 7] == secondBuffer[si + 7]
&& firstBuffer[fi + 8] == secondBuffer[si + 8]
&& firstBuffer[fi + 9] == secondBuffer[si + 9]
&& firstBuffer[fi + 10] == secondBuffer[si + 10]
&& firstBuffer[fi + 11] == secondBuffer[si + 11]
&& firstBuffer[fi + 12] == secondBuffer[si + 12]
&& firstBuffer[fi + 13] == secondBuffer[si + 13]
&& firstBuffer[fi + 14] == secondBuffer[si + 14]
&& firstBuffer[fi + 15] == secondBuffer[si + 15]
&& firstBuffer[fi + 16] == secondBuffer[si + 16]
&& firstBuffer[fi + 17] == secondBuffer[si + 17]
&& firstBuffer[fi + 18] == secondBuffer[si + 18]
&& firstBuffer[fi + 19] == secondBuffer[si + 19]
&& firstBuffer[fi + 20] == secondBuffer[si + 20]
&& firstBuffer[fi + 21] == secondBuffer[si + 21]
&& firstBuffer[fi + 22] == secondBuffer[si + 22]
&& firstBuffer[fi + 23] == secondBuffer[si + 23]
&& firstBuffer[fi + 24] == secondBuffer[si + 24]
&& firstBuffer[fi + 25] == secondBuffer[si + 25]
&& firstBuffer[fi + 26] == secondBuffer[si + 26]
&& firstBuffer[fi + 27] == secondBuffer[si + 27]
&& firstBuffer[fi + 28] == secondBuffer[si + 28]
&& firstBuffer[fi + 29] == secondBuffer[si + 29]
&& firstBuffer[fi + 30] == secondBuffer[si + 30]
&& firstBuffer[fi + 31] == secondBuffer[si + 31];
}
/**
* Convert a LongObjectId from raw binary representation.
*
* @param bs
* the raw byte buffer to read from. At least 32 bytes must be
* available within this byte array.
* @return the converted object id.
*/
public static final LongObjectId fromRaw(byte[] bs) {
return fromRaw(bs, 0);
}
/**
* Convert a LongObjectId from raw binary representation.
*
* @param bs
* the raw byte buffer to read from. At least 32 bytes after p
* must be available within this byte array.
* @param p
* position to read the first byte of data from.
* @return the converted object id.
*/
public static final LongObjectId fromRaw(byte[] bs, int p) {
final long a = NB.decodeInt64(bs, p);
final long b = NB.decodeInt64(bs, p + 8);
final long c = NB.decodeInt64(bs, p + 16);
final long d = NB.decodeInt64(bs, p + 24);
return new LongObjectId(a, b, c, d);
}
/**
* Convert a LongObjectId from raw binary representation.
*
* @param is
* the raw long buffer to read from. At least 4 longs must be
* available within this long array.
* @return the converted object id.
*/
public static final LongObjectId fromRaw(long[] is) {
return fromRaw(is, 0);
}
/**
* Convert a LongObjectId from raw binary representation.
*
* @param is
* the raw long buffer to read from. At least 4 longs after p
* must be available within this long array.
* @param p
* position to read the first long of data from.
* @return the converted object id.
*/
public static final LongObjectId fromRaw(long[] is, int p) {
return new LongObjectId(is[p], is[p + 1], is[p + 2], is[p + 3]);
}
/**
* Convert a LongObjectId from hex characters (US-ASCII).
*
* @param buf
* the US-ASCII buffer to read from. At least 64 bytes after
* offset must be available within this byte array.
* @param offset
* position to read the first character from.
* @return the converted object id.
*/
public static final LongObjectId fromString(byte[] buf, int offset) {
return fromHexString(buf, offset);
}
/**
* Convert a LongObjectId from hex characters.
*
* @param str
* the string to read from. Must be 64 characters long.
* @return the converted object id.
*/
public static LongObjectId fromString(String str) {
if (str.length() != Constants.LONG_OBJECT_ID_STRING_LENGTH)
throw new InvalidLongObjectIdException(str);
return fromHexString(org.eclipse.jgit.lib.Constants.encodeASCII(str),
0);
}
private static final LongObjectId fromHexString(byte[] bs, int p) {
try {
final long a = RawParseUtils.parseHexInt64(bs, p);
final long b = RawParseUtils.parseHexInt64(bs, p + 16);
final long c = RawParseUtils.parseHexInt64(bs, p + 32);
final long d = RawParseUtils.parseHexInt64(bs, p + 48);
return new LongObjectId(a, b, c, d);
} catch (ArrayIndexOutOfBoundsException e) {
InvalidLongObjectIdException e1 = new InvalidLongObjectIdException(
bs, p, Constants.LONG_OBJECT_ID_STRING_LENGTH);
e1.initCause(e);
throw e1;
}
}
LongObjectId(final long new_1, final long new_2, final long new_3,
final long new_4) {
w1 = new_1;
w2 = new_2;
w3 = new_3;
w4 = new_4;
}
/**
* Initialize this instance by copying another existing LongObjectId.
* <p>
* This constructor is mostly useful for subclasses which want to extend a
* LongObjectId with more properties, but initialize from an existing
* LongObjectId instance acquired by other means.
*
* @param src
* another already parsed LongObjectId to copy the value out of.
*/
protected LongObjectId(AnyLongObjectId src) {
w1 = src.w1;
w2 = src.w2;
w3 = src.w3;
w4 = src.w4;
}
/** {@inheritDoc} */
@Override
public LongObjectId toObjectId() {
return this;
}
private void writeObject(ObjectOutputStream os) throws IOException {
os.writeLong(w1);
os.writeLong(w2);
os.writeLong(w3);
os.writeLong(w4);
}
private void readObject(ObjectInputStream ois) throws IOException {
w1 = ois.readLong();
w2 = ois.readLong();
w3 = ois.readLong();
w4 = ois.readLong();
}
}