| /* |
| * Copyright (c) 2003, 2006, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code 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 |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| /* |
| */ |
| |
| |
| import java.nio.ByteBuffer; |
| import java.nio.CharBuffer; |
| import java.nio.charset.Charset; |
| import java.nio.charset.CharsetDecoder; |
| import java.nio.charset.CoderResult; |
| |
| /** |
| * An abstract base class for subclasses which decode |
| * IBM double byte ebcdic host encodings such as ibm code |
| * pages 933, 935, 937,... etc |
| * |
| */ |
| |
| public abstract class DBCS_IBM_EBCDIC_Decoder extends CharsetDecoder |
| { |
| |
| private DBCSDecoderMapping decoderMapping; |
| protected static final char REPLACE_CHAR='\uFFFD'; |
| |
| protected String singleByteToChar; |
| protected short index1[]; |
| protected String index2; |
| protected int mask1; |
| protected int mask2; |
| protected int shift; |
| |
| private static final int SBCS = 0; |
| private static final int DBCS = 1; |
| |
| private static final int SO = 0x0e; |
| private static final int SI = 0x0f; |
| private int currentState; |
| |
| protected DBCS_IBM_EBCDIC_Decoder(Charset cs) { |
| super(cs, 0.5f, 1.0f); |
| } |
| |
| protected void implReset() { |
| currentState = SBCS; |
| } |
| |
| private CoderResult decodeArrayLoop(ByteBuffer src, CharBuffer dst) { |
| byte[] sa = src.array(); |
| int sp = src.arrayOffset() + src.position(); |
| int sl = src.arrayOffset() + src.limit(); |
| assert (sp <= sl); |
| sp = (sp <= sl ? sp : sl); |
| char[] da = dst.array(); |
| int dp = dst.arrayOffset() + dst.position(); |
| int dl = dst.arrayOffset() + dst.limit(); |
| assert (dp <= dl); |
| dp = (dp <= dl ? dp : dl); |
| |
| try { |
| while (sp < sl) { |
| int b1, b2; |
| b1 = sa[sp]; |
| int inputSize = 1; |
| int v = 0; |
| char outputChar = REPLACE_CHAR; |
| |
| if (b1 < 0) |
| b1 += 256; |
| |
| if (b1 == SO) { // Shift out |
| // For SO characters - simply validate the state and if OK |
| // update the state and go to the next byte |
| |
| if (currentState != SBCS) |
| return CoderResult.malformedForLength(1); |
| else |
| currentState = DBCS; |
| } else if (b1 == SI) { |
| // For SI characters - simply validate the state and if OK |
| // update the state and go to the next byte |
| |
| if (currentState != DBCS) { |
| return CoderResult.malformedForLength(1); |
| } else { |
| currentState = SBCS; |
| } |
| } else { |
| if (currentState == SBCS) { |
| outputChar = singleByteToChar.charAt(b1); |
| } else { |
| if (sl - sp < 2) |
| return CoderResult.UNDERFLOW; |
| b2 = sa[sp + 1]; |
| if (b2 < 0) |
| b2 += 256; |
| |
| inputSize++; |
| |
| // Check validity of dbcs ebcdic byte pair values |
| if ((b1 != 0x40 || b2 != 0x40) && |
| (b2 < 0x41 || b2 > 0xfe)) { |
| return CoderResult.malformedForLength(2); |
| } |
| |
| // Lookup in the two level index |
| v = b1 * 256 + b2; |
| outputChar = index2.charAt(index1[((v & mask1) >> shift)] |
| + (v & mask2)); |
| } |
| if (outputChar == '\uFFFD') |
| return CoderResult.unmappableForLength(inputSize); |
| |
| if (dl - dp < 1) |
| return CoderResult.OVERFLOW; |
| da[dp++] = outputChar; |
| } |
| sp += inputSize; |
| } |
| return CoderResult.UNDERFLOW; |
| } finally { |
| src.position(sp - src.arrayOffset()); |
| dst.position(dp - dst.arrayOffset()); |
| } |
| } |
| |
| private CoderResult decodeBufferLoop(ByteBuffer src, CharBuffer dst) { |
| int mark = src.position(); |
| |
| try { |
| while (src.hasRemaining()) { |
| int b1, b2; |
| int v = 0; |
| b1 = src.get(); |
| int inputSize = 1; |
| char outputChar = REPLACE_CHAR; |
| |
| if (b1 < 0) |
| b1 += 256; |
| |
| |
| if (b1 == SO) { // Shift out |
| // For SO characters - simply validate the state and if OK |
| // update the state and go to the next byte |
| |
| if (currentState != SBCS) |
| return CoderResult.malformedForLength(1); |
| else |
| currentState = DBCS; |
| } else if (b1 == SI) { |
| // For SI characters - simply validate the state and if OK |
| // update the state and go to the next byte |
| |
| if (currentState != DBCS) { |
| return CoderResult.malformedForLength(1); |
| } else { |
| currentState = SBCS; |
| } |
| } else { |
| if (currentState == SBCS) { |
| outputChar = singleByteToChar.charAt(b1); |
| } else { |
| if (src.remaining() < 1) |
| return CoderResult.UNDERFLOW; |
| b2 = src.get(); |
| if (b2 < 0) |
| b2 += 256; |
| inputSize++; |
| |
| // Check validity of dbcs ebcdic byte pair values |
| if ((b1 != 0x40 || b2 != 0x40) && |
| (b2 < 0x41 || b2 > 0xfe)) { |
| return CoderResult.malformedForLength(2); |
| } |
| |
| // Lookup in the two level index |
| v = b1 * 256 + b2; |
| outputChar = index2.charAt(index1[((v & mask1) >> shift)] |
| + (v & mask2)); |
| } |
| if (outputChar == REPLACE_CHAR) |
| return CoderResult.unmappableForLength(inputSize); |
| |
| if (!dst.hasRemaining()) |
| return CoderResult.OVERFLOW; |
| dst.put(outputChar); |
| } |
| mark += inputSize; |
| } |
| return CoderResult.UNDERFLOW; |
| } finally { |
| src.position(mark); |
| } |
| } |
| |
| protected CoderResult decodeLoop(ByteBuffer src, CharBuffer dst) { |
| if (src.hasArray() && dst.hasArray()) |
| return decodeArrayLoop(src, dst); |
| else |
| return decodeBufferLoop(src, dst); |
| } |
| } |
