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diff --git a/icu/icu4j/main/classes/core/src/com/ibm/icu/text/UnicodeDecompressor.java b/icu/icu4j/main/classes/core/src/com/ibm/icu/text/UnicodeDecompressor.java
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+/*
+ *******************************************************************************
+ * Copyright (C) 1996-2016, International Business Machines Corporation and *
+ * others. All Rights Reserved. *
+ *******************************************************************************
+ */
+
+package com.ibm.icu.text;
+
+/**
+* A decompression engine implementing the Standard Compression Scheme
+* for Unicode (SCSU) as outlined in <A
+* HREF="http://www.unicode.org/unicode/reports/tr6">Unicode Technical
+* Report #6</A>.
+*
+* <P><STRONG>USAGE</STRONG></P>
+*
+* <P>The static methods on <TT>UnicodeDecompressor</TT> may be used in a
+* straightforward manner to decompress simple strings:</P>
+*
+* <PRE>
+* byte [] compressed = ... ; // get compressed bytes from somewhere
+* String result = UnicodeDecompressor.decompress(compressed);
+* </PRE>
+*
+* <P>The static methods have a fairly large memory footprint.
+* For finer-grained control over memory usage,
+* <TT>UnicodeDecompressor</TT> offers more powerful APIs allowing
+* iterative decompression:</P>
+*
+* <PRE>
+* // Decompress an array "bytes" of length "len" using a buffer of 512 chars
+* // to the Writer "out"
+*
+* UnicodeDecompressor myDecompressor = new UnicodeDecompressor();
+* final static int BUFSIZE = 512;
+* char [] charBuffer = new char [ BUFSIZE ];
+* int charsWritten = 0;
+* int [] bytesRead = new int [1];
+* int totalBytesDecompressed = 0;
+* int totalCharsWritten = 0;
+*
+* do {
+* // do the decompression
+* charsWritten = myDecompressor.decompress(bytes, totalBytesDecompressed,
+* len, bytesRead,
+* charBuffer, 0, BUFSIZE);
+*
+* // do something with the current set of chars
+* out.write(charBuffer, 0, charsWritten);
+*
+* // update the no. of bytes decompressed
+* totalBytesDecompressed += bytesRead[0];
+*
+* // update the no. of chars written
+* totalCharsWritten += charsWritten;
+*
+* } while(totalBytesDecompressed &lt; len);
+*
+* myDecompressor.reset(); // reuse decompressor
+* </PRE>
+*
+* <P>Decompression is performed according to the standard set forth in
+* <A HREF="http://www.unicode.org/unicode/reports/tr6">Unicode Technical
+* Report #6</A></P>
+*
+* @see UnicodeCompressor
+*
+* @author Stephen F. Booth
+* @stable ICU 2.4
+*/
+public final class UnicodeDecompressor implements SCSU
+{
+ //==========================
+ // Instance variables
+ //==========================
+
+ /** Alias to current dynamic window */
+ private int fCurrentWindow = 0;
+
+ /** Dynamic compression window offsets */
+ private int [] fOffsets = new int [ NUMWINDOWS ];
+
+ /** Current compression mode */
+ private int fMode = SINGLEBYTEMODE;
+
+ /** Size of our internal buffer */
+ private final static int BUFSIZE = 3;
+
+ /** Internal buffer for saving state */
+ private byte [] fBuffer = new byte [BUFSIZE];
+
+ /** Number of characters in our internal buffer */
+ private int fBufferLength = 0;
+
+
+ /**
+ * Create a UnicodeDecompressor.
+ * Sets all windows to their default values.
+ * @see #reset
+ * @stable ICU 2.4
+ */
+ public UnicodeDecompressor(){
+ reset(); // initialize to defaults
+ }
+
+ /**
+ * Decompress a byte array into a String.
+ * @param buffer The byte array to decompress.
+ * @return A String containing the decompressed characters.
+ * @see #decompress(byte [], int, int)
+ * @stable ICU 2.4
+ */
+ public static String decompress(byte [] buffer){
+ char [] buf = decompress(buffer, 0, buffer.length);
+ return new String(buf);
+ }
+
+ /**
+ * Decompress a byte array into a Unicode character array.
+ * @param buffer The byte array to decompress.
+ * @param start The start of the byte run to decompress.
+ * @param limit The limit of the byte run to decompress.
+ * @return A character array containing the decompressed bytes.
+ * @see #decompress(byte [])
+ * @stable ICU 2.4
+ */
+ public static char [] decompress(byte [] buffer, int start, int limit) {
+ UnicodeDecompressor comp = new UnicodeDecompressor();
+
+ // use a buffer we know will never overflow
+ // in the worst case, each byte will decompress
+ // to a surrogate pair (buffer must be at least 2 chars)
+ int len = Math.max(2, 2 * (limit - start));
+ char [] temp = new char [len];
+
+ int charCount = comp.decompress(buffer, start, limit, null,
+ temp, 0, len);
+
+ char [] result = new char [charCount];
+ System.arraycopy(temp, 0, result, 0, charCount);
+ return result;
+ }
+
+ /**
+ * Decompress a byte array into a Unicode character array.
+ *
+ * This function will either completely fill the output buffer,
+ * or consume the entire input.
+ *
+ * @param byteBuffer The byte buffer to decompress.
+ * @param byteBufferStart The start of the byte run to decompress.
+ * @param byteBufferLimit The limit of the byte run to decompress.
+ * @param bytesRead A one-element array. If not null, on return
+ * the number of bytes read from byteBuffer.
+ * @param charBuffer A buffer to receive the decompressed data.
+ * This buffer must be at minimum two characters in size.
+ * @param charBufferStart The starting offset to which to write
+ * decompressed data.
+ * @param charBufferLimit The limiting offset for writing
+ * decompressed data.
+ * @return The number of Unicode characters written to charBuffer.
+ * @stable ICU 2.4
+ */
+ public int decompress(byte [] byteBuffer,
+ int byteBufferStart,
+ int byteBufferLimit,
+ int [] bytesRead,
+ char [] charBuffer,
+ int charBufferStart,
+ int charBufferLimit)
+ {
+ // the current position in the source byte buffer
+ int bytePos = byteBufferStart;
+
+ // the current position in the target char buffer
+ int ucPos = charBufferStart;
+
+ // the current byte from the source buffer
+ int aByte = 0x00;
+
+
+ // charBuffer must be at least 2 chars in size
+ if(charBuffer.length < 2 || (charBufferLimit - charBufferStart) < 2)
+ throw new IllegalArgumentException("charBuffer.length < 2");
+
+ // if our internal buffer isn't empty, flush its contents
+ // to the output buffer before doing any more decompression
+ if(fBufferLength > 0) {
+
+ int newBytes = 0;
+
+ // fill the buffer completely, to guarantee one full character
+ if(fBufferLength != BUFSIZE) {
+ newBytes = fBuffer.length - fBufferLength;
+
+ // verify there are newBytes bytes in byteBuffer
+ if(byteBufferLimit - byteBufferStart < newBytes)
+ newBytes = byteBufferLimit - byteBufferStart;
+
+ System.arraycopy(byteBuffer, byteBufferStart,
+ fBuffer, fBufferLength, newBytes);
+ }
+
+ // reset buffer length to 0 before recursive call
+ fBufferLength = 0;
+
+ // call self recursively to decompress the buffer
+ int count = decompress(fBuffer, 0, fBuffer.length, null,
+ charBuffer, charBufferStart,
+ charBufferLimit);
+
+ // update the positions into the arrays
+ ucPos += count;
+ bytePos += newBytes;
+ }
+
+ // the main decompression loop
+ mainLoop:
+ while(bytePos < byteBufferLimit && ucPos < charBufferLimit) {
+ switch(fMode) {
+ case SINGLEBYTEMODE:
+ // single-byte mode decompression loop
+ singleByteModeLoop:
+ while(bytePos < byteBufferLimit && ucPos < charBufferLimit) {
+ aByte = byteBuffer[bytePos++] & 0xFF;
+ switch(aByte) {
+ // All bytes from 0x80 through 0xFF are remapped
+ // to chars or surrogate pairs according to the
+ // currently active window
+ case 0x80: case 0x81: case 0x82: case 0x83: case 0x84:
+ case 0x85: case 0x86: case 0x87: case 0x88: case 0x89:
+ case 0x8A: case 0x8B: case 0x8C: case 0x8D: case 0x8E:
+ case 0x8F: case 0x90: case 0x91: case 0x92: case 0x93:
+ case 0x94: case 0x95: case 0x96: case 0x97: case 0x98:
+ case 0x99: case 0x9A: case 0x9B: case 0x9C: case 0x9D:
+ case 0x9E: case 0x9F: case 0xA0: case 0xA1: case 0xA2:
+ case 0xA3: case 0xA4: case 0xA5: case 0xA6: case 0xA7:
+ case 0xA8: case 0xA9: case 0xAA: case 0xAB: case 0xAC:
+ case 0xAD: case 0xAE: case 0xAF: case 0xB0: case 0xB1:
+ case 0xB2: case 0xB3: case 0xB4: case 0xB5: case 0xB6:
+ case 0xB7: case 0xB8: case 0xB9: case 0xBA: case 0xBB:
+ case 0xBC: case 0xBD: case 0xBE: case 0xBF: case 0xC0:
+ case 0xC1: case 0xC2: case 0xC3: case 0xC4: case 0xC5:
+ case 0xC6: case 0xC7: case 0xC8: case 0xC9: case 0xCA:
+ case 0xCB: case 0xCC: case 0xCD: case 0xCE: case 0xCF:
+ case 0xD0: case 0xD1: case 0xD2: case 0xD3: case 0xD4:
+ case 0xD5: case 0xD6: case 0xD7: case 0xD8: case 0xD9:
+ case 0xDA: case 0xDB: case 0xDC: case 0xDD: case 0xDE:
+ case 0xDF: case 0xE0: case 0xE1: case 0xE2: case 0xE3:
+ case 0xE4: case 0xE5: case 0xE6: case 0xE7: case 0xE8:
+ case 0xE9: case 0xEA: case 0xEB: case 0xEC: case 0xED:
+ case 0xEE: case 0xEF: case 0xF0: case 0xF1: case 0xF2:
+ case 0xF3: case 0xF4: case 0xF5: case 0xF6: case 0xF7:
+ case 0xF8: case 0xF9: case 0xFA: case 0xFB: case 0xFC:
+ case 0xFD: case 0xFE: case 0xFF:
+ // For offsets <= 0xFFFF, convert to a single char
+ // by adding the window's offset and subtracting
+ // the generic compression offset
+ if(fOffsets[ fCurrentWindow ] <= 0xFFFF) {
+ charBuffer[ucPos++] = (char)
+ (aByte + fOffsets[ fCurrentWindow ]
+ - COMPRESSIONOFFSET);
+ }
+ // For offsets > 0x10000, convert to a surrogate pair by
+ // normBase = window's offset - 0x10000
+ // high surr. = 0xD800 + (normBase >> 10)
+ // low surr. = 0xDC00 + (normBase & 0x3FF) + (byte & 0x7F)
+ else {
+ // make sure there is enough room to write
+ // both characters
+ // if not, save state and break out
+ if((ucPos + 1) >= charBufferLimit) {
+ --bytePos;
+ System.arraycopy(byteBuffer, bytePos,
+ fBuffer, 0,
+ byteBufferLimit - bytePos);
+ fBufferLength = byteBufferLimit - bytePos;
+ bytePos += fBufferLength;
+ break mainLoop;
+ }
+
+ int normalizedBase = fOffsets[ fCurrentWindow ]
+ - 0x10000;
+ charBuffer[ucPos++] = (char)
+ (0xD800 + (normalizedBase >> 10));
+ charBuffer[ucPos++] = (char)
+ (0xDC00 + (normalizedBase & 0x3FF)+(aByte & 0x7F));
+ }
+ break;
+
+ // bytes from 0x20 through 0x7F are treated as ASCII and
+ // are remapped to chars by padding the high byte
+ // (this is the same as quoting from static window 0)
+ // NUL (0x00), HT (0x09), CR (0x0A), LF (0x0D)
+ // are treated as ASCII as well
+ case 0x00: case 0x09: case 0x0A: case 0x0D:
+ case 0x20: case 0x21: case 0x22: case 0x23: case 0x24:
+ case 0x25: case 0x26: case 0x27: case 0x28: case 0x29:
+ case 0x2A: case 0x2B: case 0x2C: case 0x2D: case 0x2E:
+ case 0x2F: case 0x30: case 0x31: case 0x32: case 0x33:
+ case 0x34: case 0x35: case 0x36: case 0x37: case 0x38:
+ case 0x39: case 0x3A: case 0x3B: case 0x3C: case 0x3D:
+ case 0x3E: case 0x3F: case 0x40: case 0x41: case 0x42:
+ case 0x43: case 0x44: case 0x45: case 0x46: case 0x47:
+ case 0x48: case 0x49: case 0x4A: case 0x4B: case 0x4C:
+ case 0x4D: case 0x4E: case 0x4F: case 0x50: case 0x51:
+ case 0x52: case 0x53: case 0x54: case 0x55: case 0x56:
+ case 0x57: case 0x58: case 0x59: case 0x5A: case 0x5B:
+ case 0x5C: case 0x5D: case 0x5E: case 0x5F: case 0x60:
+ case 0x61: case 0x62: case 0x63: case 0x64: case 0x65:
+ case 0x66: case 0x67: case 0x68: case 0x69: case 0x6A:
+ case 0x6B: case 0x6C: case 0x6D: case 0x6E: case 0x6F:
+ case 0x70: case 0x71: case 0x72: case 0x73: case 0x74:
+ case 0x75: case 0x76: case 0x77: case 0x78: case 0x79:
+ case 0x7A: case 0x7B: case 0x7C: case 0x7D: case 0x7E:
+ case 0x7F:
+ charBuffer[ucPos++] = (char) aByte;
+ break;
+
+ // quote unicode
+ case SQUOTEU:
+ // verify we have two bytes following tag
+ // if not, save state and break out
+ if( (bytePos + 1) >= byteBufferLimit ) {
+ --bytePos;
+ System.arraycopy(byteBuffer, bytePos,
+ fBuffer, 0,
+ byteBufferLimit - bytePos);
+ fBufferLength = byteBufferLimit - bytePos;
+ bytePos += fBufferLength;
+ break mainLoop;
+ }
+
+ aByte = byteBuffer[bytePos++];
+ charBuffer[ucPos++] = (char)
+ (aByte << 8 | (byteBuffer[bytePos++] & 0xFF));
+ break;
+
+ // switch to Unicode mode
+ case SCHANGEU:
+ fMode = UNICODEMODE;
+ break singleByteModeLoop;
+ //break;
+
+ // handle all quote tags
+ case SQUOTE0: case SQUOTE1: case SQUOTE2: case SQUOTE3:
+ case SQUOTE4: case SQUOTE5: case SQUOTE6: case SQUOTE7:
+ // verify there is a byte following the tag
+ // if not, save state and break out
+ if(bytePos >= byteBufferLimit) {
+ --bytePos;
+ System.arraycopy(byteBuffer, bytePos,
+ fBuffer, 0,
+ byteBufferLimit - bytePos);
+ fBufferLength = byteBufferLimit - bytePos;
+ bytePos += fBufferLength;
+ break mainLoop;
+ }
+
+ // if the byte is in the range 0x00 - 0x7F, use
+ // static window n otherwise, use dynamic window n
+ int dByte = byteBuffer[bytePos++] & 0xFF;
+ charBuffer[ucPos++] = (char)
+ (dByte+ (dByte >= 0x00 && dByte < 0x80
+ ? sOffsets[aByte - SQUOTE0]
+ : (fOffsets[aByte - SQUOTE0]
+ - COMPRESSIONOFFSET)));
+ break;
+
+ // handle all change tags
+ case SCHANGE0: case SCHANGE1: case SCHANGE2: case SCHANGE3:
+ case SCHANGE4: case SCHANGE5: case SCHANGE6: case SCHANGE7:
+ fCurrentWindow = aByte - SCHANGE0;
+ break;
+
+ // handle all define tags
+ case SDEFINE0: case SDEFINE1: case SDEFINE2: case SDEFINE3:
+ case SDEFINE4: case SDEFINE5: case SDEFINE6: case SDEFINE7:
+ // verify there is a byte following the tag
+ // if not, save state and break out
+ if(bytePos >= byteBufferLimit) {
+ --bytePos;
+ System.arraycopy(byteBuffer, bytePos,
+ fBuffer, 0,
+ byteBufferLimit - bytePos);
+ fBufferLength = byteBufferLimit - bytePos;
+ bytePos += fBufferLength;
+ break mainLoop;
+ }
+
+ fCurrentWindow = aByte - SDEFINE0;
+ fOffsets[fCurrentWindow] =
+ sOffsetTable[byteBuffer[bytePos++] & 0xFF];
+ break;
+
+ // handle define extended tag
+ case SDEFINEX:
+ // verify we have two bytes following tag
+ // if not, save state and break out
+ if((bytePos + 1) >= byteBufferLimit ) {
+ --bytePos;
+ System.arraycopy(byteBuffer, bytePos,
+ fBuffer, 0,
+ byteBufferLimit - bytePos);
+ fBufferLength = byteBufferLimit - bytePos;
+ bytePos += fBufferLength;
+ break mainLoop;
+ }
+
+ aByte = byteBuffer[bytePos++] & 0xFF;
+ fCurrentWindow = (aByte & 0xE0) >> 5;
+ fOffsets[fCurrentWindow] = 0x10000 +
+ (0x80 * (((aByte & 0x1F) << 8)
+ | (byteBuffer[bytePos++] & 0xFF)));
+ break;
+
+ // reserved, shouldn't happen
+ case SRESERVED:
+ break;
+
+ } // end switch
+ } // end while
+ break;
+
+ case UNICODEMODE:
+ // unicode mode decompression loop
+ unicodeModeLoop:
+ while(bytePos < byteBufferLimit && ucPos < charBufferLimit) {
+ aByte = byteBuffer[bytePos++] & 0xFF;
+ switch(aByte) {
+ // handle all define tags
+ case UDEFINE0: case UDEFINE1: case UDEFINE2: case UDEFINE3:
+ case UDEFINE4: case UDEFINE5: case UDEFINE6: case UDEFINE7:
+ // verify there is a byte following tag
+ // if not, save state and break out
+ if(bytePos >= byteBufferLimit ) {
+ --bytePos;
+ System.arraycopy(byteBuffer, bytePos,
+ fBuffer, 0,
+ byteBufferLimit - bytePos);
+ fBufferLength = byteBufferLimit - bytePos;
+ bytePos += fBufferLength;
+ break mainLoop;
+ }
+
+ fCurrentWindow = aByte - UDEFINE0;
+ fOffsets[fCurrentWindow] =
+ sOffsetTable[byteBuffer[bytePos++] & 0xFF];
+ fMode = SINGLEBYTEMODE;
+ break unicodeModeLoop;
+ //break;
+
+ // handle define extended tag
+ case UDEFINEX:
+ // verify we have two bytes following tag
+ // if not, save state and break out
+ if((bytePos + 1) >= byteBufferLimit ) {
+ --bytePos;
+ System.arraycopy(byteBuffer, bytePos,
+ fBuffer, 0,
+ byteBufferLimit - bytePos);
+ fBufferLength = byteBufferLimit - bytePos;
+ bytePos += fBufferLength;
+ break mainLoop;
+ }
+
+ aByte = byteBuffer[bytePos++] & 0xFF;
+ fCurrentWindow = (aByte & 0xE0) >> 5;
+ fOffsets[fCurrentWindow] = 0x10000 +
+ (0x80 * (((aByte & 0x1F) << 8)
+ | (byteBuffer[bytePos++] & 0xFF)));
+ fMode = SINGLEBYTEMODE;
+ break unicodeModeLoop;
+ //break;
+
+ // handle all change tags
+ case UCHANGE0: case UCHANGE1: case UCHANGE2: case UCHANGE3:
+ case UCHANGE4: case UCHANGE5: case UCHANGE6: case UCHANGE7:
+ fCurrentWindow = aByte - UCHANGE0;
+ fMode = SINGLEBYTEMODE;
+ break unicodeModeLoop;
+ //break;
+
+ // quote unicode
+ case UQUOTEU:
+ // verify we have two bytes following tag
+ // if not, save state and break out
+ if(bytePos >= byteBufferLimit - 1) {
+ --bytePos;
+ System.arraycopy(byteBuffer, bytePos,
+ fBuffer, 0,
+ byteBufferLimit - bytePos);
+ fBufferLength = byteBufferLimit - bytePos;
+ bytePos += fBufferLength;
+ break mainLoop;
+ }
+
+ aByte = byteBuffer[bytePos++];
+ charBuffer[ucPos++] = (char)
+ (aByte << 8 | (byteBuffer[bytePos++] & 0xFF));
+ break;
+
+ default:
+ // verify there is a byte following tag
+ // if not, save state and break out
+ if(bytePos >= byteBufferLimit ) {
+ --bytePos;
+ System.arraycopy(byteBuffer, bytePos,
+ fBuffer, 0,
+ byteBufferLimit - bytePos);
+ fBufferLength = byteBufferLimit - bytePos;
+ bytePos += fBufferLength;
+ break mainLoop;
+ }
+
+ charBuffer[ucPos++] = (char)
+ (aByte << 8 | (byteBuffer[bytePos++] & 0xFF));
+ break;
+
+ } // end switch
+ } // end while
+ break;
+
+ } // end switch( fMode )
+ } // end while
+
+ // fill in output parameter
+ if(bytesRead != null)
+ bytesRead [0] = (bytePos - byteBufferStart);
+
+ // return # of chars written
+ return (ucPos - charBufferStart);
+ }
+
+ /**
+ * Reset the decompressor to its initial state.
+ * @stable ICU 2.4
+ */
+ public void reset()
+ {
+ // reset dynamic windows
+ fOffsets[0] = 0x0080; // Latin-1
+ fOffsets[1] = 0x00C0; // Latin-1 Supplement + Latin Extended-A
+ fOffsets[2] = 0x0400; // Cyrillic
+ fOffsets[3] = 0x0600; // Arabic
+ fOffsets[4] = 0x0900; // Devanagari
+ fOffsets[5] = 0x3040; // Hiragana
+ fOffsets[6] = 0x30A0; // Katakana
+ fOffsets[7] = 0xFF00; // Fullwidth ASCII
+
+
+ fCurrentWindow = 0; // Make current window Latin-1
+ fMode = SINGLEBYTEMODE; // Always start in single-byte mode
+ fBufferLength = 0; // Empty buffer
+ }
+}
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