io.github.eb4j.pdic.IndexCache Maven / Gradle / Ivy
/*
* PDIC4j, a PDIC dictionary access library.
* Copyright (C) 2022 Hiroshi Miura.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see > mMap = new WeakHashMap<>();
private byte[] fixedBuffer;
IndexCache(final RandomAccessFile file, final int start, final int size) {
randomAccessFile = file;
this.start = start;
this.size = size;
if (this.size < 1024 * 512) {
fix = true;
segmentBlockSize = this.size;
} else {
fix = false;
segmentBlockSize = 1024;
}
}
byte[] getSegment(final int segment) {
byte[] segmentData = null;
if (fix) {
if (fixedBuffer == null) {
fixedBuffer = new byte[size];
try {
randomAccessFile.seek(start);
if (randomAccessFile.read(fixedBuffer, 0, size) >= 0) {
return fixedBuffer;
}
} catch (IOException ignored) {
}
}
}
WeakReference ref = mMap.get(segment);
if (ref != null) {
segmentData = ref.get();
}
if (segmentData == null) {
segmentData = new byte[segmentBlockSize];
try {
randomAccessFile.seek(start + (long) segment * segmentBlockSize);
int len = randomAccessFile.read(segmentData, 0, segmentBlockSize);
if (len == segmentBlockSize || len == size % segmentBlockSize) {
mMap.put(segment, new WeakReference<>(segmentData));
} else {
return null;
}
} catch (IOException e) {
return null;
}
}
return segmentData;
}
public int getShort(final int ptr) {
int segment = ptr / segmentBlockSize;
int address = ptr % segmentBlockSize;
byte[] segmentdata = getSegment(segment++);
int dat = 0;
if (segmentdata != null) {
int b;
b = segmentdata[address++];
b &= 0xFF;
dat |= b;
if (address >= segmentBlockSize) {
address %= segmentBlockSize;
segmentdata = getSegment(segment);
}
b = segmentdata[address];
b &= 0xFF;
dat |= (b << 8);
}
return dat;
}
public int getInt(final int ptr) {
int segment = ptr / segmentBlockSize;
int address = ptr % segmentBlockSize;
byte[] segmentdata = getSegment(segment++);
int dat = 0;
if (segmentdata != null) {
int b;
b = segmentdata[address++];
b &= 0xFF;
dat |= b;
if (address >= segmentBlockSize) {
address %= segmentBlockSize;
segmentdata = getSegment(segment++);
}
b = segmentdata[address++];
b &= 0xFF;
dat |= (b << 8);
if (address >= segmentBlockSize) {
address %= segmentBlockSize;
segmentdata = getSegment(segment++);
}
b = segmentdata[address++];
b &= 0xFF;
dat |= (b << 16);
if (address >= segmentBlockSize) {
address %= segmentBlockSize;
segmentdata = getSegment(segment);
}
b = segmentdata[address];
b &= 0x7F;
dat |= (b << 24);
}
return dat;
}
@SuppressWarnings("finalparameters")
private static int compareArrayAsUnsigned(byte[] aa, int pa, int la, byte[] ab, int pb, int lb) {
while (la-- > 0) {
short sa = aa[pa++];
if (lb-- > 0) {
short sb = ab[pb++];
if (sa != sb) {
sa &= 0xFF;
sb &= 0xFF;
return (sa - sb);
}
} else {
return 1;
}
}
if (lb > 0) {
short sb = ab[pb];
if (sb == 0x09) { // 比較対象の'\t'は'\0'とみなす
return 0;
}
return -1;
}
return 0;
}
/**
*
* @param aa
* @param pa
* @param la
* @param ptr
* @param len
* @return
*/
@SuppressWarnings("finalparameters")
public int compare(final byte[] aa, final int pa, final int la, final int ptr, final int len) {
int segment = ptr / segmentBlockSize;
int address = ptr % segmentBlockSize;
byte[] segmentdata = getSegment(segment++);
if (segmentdata == null) {
return -1;
}
if (len < 0) {
return 1;
}
if (address + len < segmentBlockSize) {
Utils.decodetoCharBuffer(CharsetICU.forNameICU("BOCU-1"), segmentdata, address, len);
return compareArrayAsUnsigned(aa, pa, la, segmentdata, address, len);
} else {
int lena = segmentBlockSize - address;
int leno = Math.min(la, lena);
int ret = compareArrayAsUnsigned(aa, pa, leno, segmentdata, address, lena);
Utils.decodetoCharBuffer(CharsetICU.forNameICU("BOCU-1"), segmentdata, address, lena);
if (ret != 0) {
return ret;
}
if (la < lena) {
return -1;
}
address = 0;
segmentdata = getSegment(segment);
Utils.decodetoCharBuffer(CharsetICU.forNameICU("BOCU-1"), segmentdata, address, len - lena);
return compareArrayAsUnsigned(aa, pa + lena, la - lena, segmentdata, address, len - lena);
}
}
/**
* Create index of words.
* @param blockBits
* @param nIndex
* @param indexPtr
* @return true when success, otherwise false.
*/
public boolean createIndex(final int blockBits, final int nIndex, final int[] indexPtr) {
// インデックスの先頭から見出し語のポインタを拾っていく
final int blockSize = 64 * 1024;
int[] params = new int[]{0, 0, nIndex, blockSize, blockBits, 1, 0};
boolean hasNext = true;
for (int i = 0; hasNext; i++) {
hasNext = countIndexWords(params, getSegment(i), indexPtr);
}
indexPtr[params[0]] = params[1] + blockBits; // ターミネータを入れておく
return true;
}
private boolean countIndexWords(final int[] params, final byte[] buff, final int[] indexPtr) {
int curidx = params[0];
int curptr = params[1];
int max = params[2];
int buffmax = params[3];
int blockBits = params[4];
int found = params[5];
int ignore = params[6];
int i = 0;
for (; i < buffmax && curidx < max; i++) {
if (ignore > 0) {
ignore--;
} else if (found != 0) {
int ptr = curptr + i + blockBits; // ブロック番号サイズポインタを進める
indexPtr[curidx++] = ptr; // 見出し語部分のポインタを保存
ignore = blockBits - 1;
found = 0;
} else if (buff[i] == 0) {
found = 1;
}
}
params[0] = curidx;
params[1] = curptr + i;
params[5] = found;
params[6] = ignore;
return curidx < max;
}
}
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