diff options
Diffstat (limited to 'src/java/com/healthmarketscience/jackcess/Index.java')
| -rw-r--r-- | src/java/com/healthmarketscience/jackcess/Index.java | 162 |
1 files changed, 65 insertions, 97 deletions
diff --git a/src/java/com/healthmarketscience/jackcess/Index.java b/src/java/com/healthmarketscience/jackcess/Index.java index 3bf9c8d..989af91 100644 --- a/src/java/com/healthmarketscience/jackcess/Index.java +++ b/src/java/com/healthmarketscience/jackcess/Index.java @@ -27,7 +27,6 @@ King of Prussia, PA 19406 package com.healthmarketscience.jackcess; -import java.io.ByteArrayOutputStream; import java.io.IOException; import java.nio.ByteBuffer; import java.nio.ByteOrder; @@ -42,6 +41,7 @@ import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import static com.healthmarketscience.jackcess.IndexCodes.*; +import static com.healthmarketscience.jackcess.ByteUtil.ByteStream; /** @@ -162,6 +162,8 @@ public abstract class Index implements Comparable<Index> { /** temp buffer used to read/write the index pages */ private final TempBufferHolder _indexBufferH = TempBufferHolder.newHolder(TempBufferHolder.Type.SOFT, true); + /** temp buffer used to create index entries */ + private ByteStream _entryBuffer; /** max size for all the entries written to a given index data page */ private final int _maxPageEntrySize; /** FIXME, for now, we can't write multi-page indexes or indexes using the funky primary key compression scheme */ @@ -949,7 +951,10 @@ public abstract class Index implements Comparable<Index> { return null; } - ByteArrayOutputStream bout = new ByteArrayOutputStream(); + if(_entryBuffer == null) { + _entryBuffer = new ByteStream(); + } + _entryBuffer.reset(); for(ColumnDescriptor col : _columns) { Object value = values[col.getColumnIndex()]; @@ -958,10 +963,10 @@ public abstract class Index implements Comparable<Index> { continue; } - col.writeValue(value, bout); + col.writeValue(value, _entryBuffer); } - return bout.toByteArray(); + return _entryBuffer.toByteArray(); } /** @@ -1002,7 +1007,14 @@ public abstract class Index implements Comparable<Index> { * Flips all the bits in the byte array. */ private static byte[] flipBytes(byte[] value) { - for(int i = 0; i < value.length; ++i) { + return flipBytes(value, 0, value.length); + } + + /** + * Flips the bits in the specified bytes in the byte array. + */ + private static byte[] flipBytes(byte[] value, int offset, int length) { + for(int i = offset; i < (offset + length); ++i) { value[i] = (byte)(~value[i]); } return value; @@ -1023,7 +1035,7 @@ public abstract class Index implements Comparable<Index> { * is based on a variety of nifty codes). */ private static void writeNonNullIndexTextValue( - Object value, ByteArrayOutputStream bout, boolean isAscending) + Object value, ByteStream bout, boolean isAscending) throws IOException { // first, convert to string @@ -1034,18 +1046,15 @@ public abstract class Index implements Comparable<Index> { if(str.length() > MAX_TEXT_INDEX_CHAR_LENGTH) { str = str.substring(0, MAX_TEXT_INDEX_CHAR_LENGTH); } - - ByteArrayOutputStream tmpBout = bout; - if(!isAscending) { - // we need to accumulate the bytes in a temp array in order to negate - // them before writing them to the final array - tmpBout = new ByteArrayOutputStream(); - } + + // record pprevious entry length so we can do any post-processing + // necessary for this entry (handling descending) + int prevLength = bout.getLength(); // now, convert each character to a "code" of one or more bytes - ExtraCodesOutputStream extraCodes = null; - ExtraCodesOutputStream unprintableCodes = null; - ExtraCodesOutputStream crazyCodes = null; + ExtraCodesStream extraCodes = null; + ByteStream unprintableCodes = null; + ByteStream crazyCodes = null; int charOffset = 0; for(int i = 0; i < str.length(); ++i) { @@ -1056,7 +1065,7 @@ public abstract class Index implements Comparable<Index> { byte[] bytes = ch.getInlineBytes(); if(bytes != null) { // write the "inline" codes immediately - tmpBout.write(bytes); + bout.write(bytes); // only increment the charOffset for chars with inline codes ++charOffset; @@ -1071,7 +1080,7 @@ public abstract class Index implements Comparable<Index> { byte extraCodeModifier = ch.getExtraByteModifier(); if((bytes != null) || (extraCodeModifier != 0)) { if(extraCodes == null) { - extraCodes = new ExtraCodesOutputStream(str.length()); + extraCodes = new ExtraCodesStream(str.length()); } // keep track of the extra codes for later @@ -1081,7 +1090,7 @@ public abstract class Index implements Comparable<Index> { bytes = ch.getUnprintableBytes(); if(bytes != null) { if(unprintableCodes == null) { - unprintableCodes = new ExtraCodesOutputStream(); + unprintableCodes = new ByteStream(); } // keep track of the unprintable codes for later @@ -1091,7 +1100,7 @@ public abstract class Index implements Comparable<Index> { byte crazyFlag = ch.getCrazyFlag(); if(crazyFlag != 0) { if(crazyCodes == null) { - crazyCodes = new ExtraCodesOutputStream(); + crazyCodes = new ByteStream(); } // keep track of the crazy flags for later @@ -1100,7 +1109,7 @@ public abstract class Index implements Comparable<Index> { } // write end text flag - tmpBout.write(END_TEXT); + bout.write(END_TEXT); boolean hasExtraCodes = trimExtraCodes( extraCodes, (byte)0, INTERNATIONAL_EXTRA_PLACEHOLDER); @@ -1110,27 +1119,27 @@ public abstract class Index implements Comparable<Index> { // we write all the international extra bytes first if(hasExtraCodes) { - extraCodes.writeTo(tmpBout); + extraCodes.writeTo(bout); } if(hasCrazyCodes || hasUnprintableCodes) { // write 2 more end flags - tmpBout.write(END_TEXT); - tmpBout.write(END_TEXT); + bout.write(END_TEXT); + bout.write(END_TEXT); // next come the crazy flags if(hasCrazyCodes) { - writeCrazyCodes(crazyCodes, tmpBout); + writeCrazyCodes(crazyCodes, bout); } // then we write all the unprintable extra bytes if(hasUnprintableCodes) { // write another end flag - tmpBout.write(END_TEXT); + bout.write(END_TEXT); - unprintableCodes.writeTo(tmpBout); + unprintableCodes.writeTo(bout); } } } @@ -1140,12 +1149,10 @@ public abstract class Index implements Comparable<Index> { // we actually write the end byte before flipping the bytes, and write // another one after flipping - tmpBout.write(END_EXTRA_TEXT); + bout.write(END_EXTRA_TEXT); - // we actually wrote into a temporary array so that we can invert the - // bytes before writing them to the final array - bout.write(flipBytes(tmpBout.toByteArray())); - + // flip the bytes that we have written thus far for this text value + flipBytes(bout.getBytes(), prevLength, (bout.getLength() - prevLength)); } // write end extra text @@ -1154,14 +1161,14 @@ public abstract class Index implements Comparable<Index> { private static void writeExtraCodes( int charOffset, byte[] bytes, byte extraCodeModifier, - ExtraCodesOutputStream extraCodes) + ExtraCodesStream extraCodes) throws IOException { // we fill in a placeholder value for any chars w/out extra codes int numChars = extraCodes.getNumChars(); if(numChars < charOffset) { int fillChars = charOffset - numChars; - extraCodes.write(fillChars, INTERNATIONAL_EXTRA_PLACEHOLDER); + extraCodes.writeFill(fillChars, INTERNATIONAL_EXTRA_PLACEHOLDER); extraCodes.incrementNumChars(fillChars); } @@ -1175,7 +1182,7 @@ public abstract class Index implements Comparable<Index> { // the extra code modifier is added to the last extra code written. if // there is no previous extra code, it is made the first extra code. - int lastIdx = extraCodes.size() - 1; + int lastIdx = extraCodes.getLength() - 1; if(lastIdx >= 0) { byte lastByte = extraCodes.get(lastIdx); lastByte += extraCodeModifier; @@ -1186,7 +1193,7 @@ public abstract class Index implements Comparable<Index> { } } - private static boolean trimExtraCodes(ExtraCodesOutputStream extraCodes, + private static boolean trimExtraCodes(ByteStream extraCodes, byte minTrimCode, byte maxTrimCode) throws IOException { @@ -1194,14 +1201,14 @@ public abstract class Index implements Comparable<Index> { return false; } - extraCodes.trimTrailingBytes(minTrimCode, maxTrimCode); + extraCodes.trimTrailing(minTrimCode, maxTrimCode); // anything left? - return (extraCodes.size() > 0); + return (extraCodes.getLength() > 0); } private static void writeUnprintableCodes( - int charOffset, byte[] bytes, ExtraCodesOutputStream extraCodes) + int charOffset, byte[] bytes, ByteStream extraCodes) throws IOException { // we write a whacky combo of bytes for each unprintable char which @@ -1219,20 +1226,19 @@ public abstract class Index implements Comparable<Index> { extraCodes.write(bytes); } - private static void writeCrazyCodes(ExtraCodesOutputStream crazyCodes, - ByteArrayOutputStream tmpBout) + private static void writeCrazyCodes(ByteStream crazyCodes, ByteStream bout) throws IOException { // CRAZY_CODE_2 flags at the end are ignored, so ditch them trimExtraCodes(crazyCodes, CRAZY_CODE_2, CRAZY_CODE_2); - if(crazyCodes.size() > 0) { + if(crazyCodes.getLength() > 0) { // the crazy codes get encoded into 6 bit sequences where each code is 2 // bits (where the first 2 bits in the byte are a common prefix). byte curByte = CRAZY_CODE_START; int idx = 0; - for(int i = 0; i < crazyCodes.size(); ++i) { + for(int i = 0; i < crazyCodes.getLength(); ++i) { byte nextByte = crazyCodes.get(i); nextByte <<= ((2 - idx) * 2); curByte |= nextByte; @@ -1240,7 +1246,7 @@ public abstract class Index implements Comparable<Index> { ++idx; if(idx == 3) { // write current byte and reset - tmpBout.write(curByte); + bout.write(curByte); curByte = CRAZY_CODE_START; idx = 0; } @@ -1248,13 +1254,13 @@ public abstract class Index implements Comparable<Index> { // write last byte if(idx > 0) { - tmpBout.write(curByte); + bout.write(curByte); } } // write crazy code suffix (note, we write this even if all the codes are // trmmed - tmpBout.write(CRAZY_CODES_SUFFIX); + bout.write(CRAZY_CODES_SUFFIX); } /** @@ -1371,7 +1377,7 @@ public abstract class Index implements Comparable<Index> { return (value == null); } - protected final void writeValue(Object value, ByteArrayOutputStream bout) + protected final void writeValue(Object value, ByteStream bout) throws IOException { if(isNullValue(value)) { @@ -1387,7 +1393,7 @@ public abstract class Index implements Comparable<Index> { } protected abstract void writeNonNullValue( - Object value, ByteArrayOutputStream bout) + Object value, ByteStream bout) throws IOException; @Override @@ -1409,7 +1415,7 @@ public abstract class Index implements Comparable<Index> { @Override protected void writeNonNullValue( - Object value, ByteArrayOutputStream bout) + Object value, ByteStream bout) throws IOException { byte[] valueBytes = encodeNumberColumnValue(value, getColumn()); @@ -1441,7 +1447,7 @@ public abstract class Index implements Comparable<Index> { @Override protected void writeNonNullValue( - Object value, ByteArrayOutputStream bout) + Object value, ByteStream bout) throws IOException { byte[] valueBytes = encodeNumberColumnValue(value, getColumn()); @@ -1481,7 +1487,7 @@ public abstract class Index implements Comparable<Index> { @Override protected void writeNonNullValue( - Object value, ByteArrayOutputStream bout) + Object value, ByteStream bout) throws IOException { byte[] valueBytes = encodeNumberColumnValue(value, getColumn()); @@ -1520,7 +1526,7 @@ public abstract class Index implements Comparable<Index> { @Override protected void writeNonNullValue( - Object value, ByteArrayOutputStream bout) + Object value, ByteStream bout) throws IOException { byte[] valueBytes = encodeNumberColumnValue(value, getColumn()); @@ -1554,7 +1560,7 @@ public abstract class Index implements Comparable<Index> { } @Override - protected void writeNonNullValue(Object value, ByteArrayOutputStream bout) + protected void writeNonNullValue(Object value, ByteStream bout) throws IOException { bout.write( @@ -1577,7 +1583,7 @@ public abstract class Index implements Comparable<Index> { @Override protected void writeNonNullValue( - Object value, ByteArrayOutputStream bout) + Object value, ByteStream bout) throws IOException { writeNonNullIndexTextValue(value, bout, isAscending()); @@ -1597,7 +1603,7 @@ public abstract class Index implements Comparable<Index> { @Override protected void writeNonNullValue( - Object value, ByteArrayOutputStream bout) + Object value, ByteStream bout) throws IOException { byte[] valueBytes = encodeNumberColumnValue(value, getColumn()); @@ -1631,7 +1637,7 @@ public abstract class Index implements Comparable<Index> { } @Override - protected void writeNonNullValue(Object value, ByteArrayOutputStream bout) + protected void writeNonNullValue(Object value, ByteStream bout) throws IOException { throw new UnsupportedOperationException("should not be called"); @@ -2381,19 +2387,13 @@ public abstract class Index implements Comparable<Index> { /** - * Extension of ByteArrayOutputStream which allows more complex access to - * the underlying bytes, as well as keeps track of an additional char count. + * Extension of ByteStream which keeps track of an additional char count. */ - private static final class ExtraCodesOutputStream - extends ByteArrayOutputStream + private static final class ExtraCodesStream extends ByteStream { private int numChars; - private ExtraCodesOutputStream() { - super(); - } - - private ExtraCodesOutputStream(int length) { + private ExtraCodesStream(int length) { super(length); } @@ -2401,41 +2401,9 @@ public abstract class Index implements Comparable<Index> { return numChars; } - public byte get(int offset) { - return buf[offset]; - } - - public void set(int offset, byte b) { - buf[offset] = b; - } - - public void write(int numBytes, byte b) { - for(int i = 0; i < numBytes; ++i) { - write(b); - } - } - public void incrementNumChars(int inc) { numChars += inc; } - - public void trimTrailingBytes(byte minTrimCode, byte maxTrimCode) - { - int minTrim = ByteUtil.asUnsignedByte(minTrimCode); - int maxTrim = ByteUtil.asUnsignedByte(maxTrimCode); - - int idx = count - 1; - while(idx >= 0) { - int val = ByteUtil.asUnsignedByte(get(idx)); - if((val >= minTrim) && (val <= maxTrim)) { - --idx; - } else { - break; - } - } - - count = idx + 1; - } } } |