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package org.codehaus.jackson.impl;

import java.io.*;
import java.math.BigDecimal;
import java.math.BigInteger;

import org.codehaus.jackson.*;
import org.codehaus.jackson.io.*;
import org.codehaus.jackson.util.CharTypes;

public final class WriterBasedGenerator
    extends JsonGeneratorBase
{
    final static int SHORT_WRITE = 32;

    final static char[] HEX_CHARS = "0123456789ABCDEF".toCharArray();

    /*
    ////////////////////////////////////////////////////
    // Configuration
    ////////////////////////////////////////////////////
     */

    final protected IOContext _ioContext;

    final protected Writer _writer;
    
    /*
    ////////////////////////////////////////////////////
    // Output buffering
    ////////////////////////////////////////////////////
     */

    /**
     * Intermediate buffer in which contents are buffered before
     * being written using {@link #_writer}.
     */
    protected char[] _outputBuffer;

    /**
     * Pointer to the first buffered character to output
     */
    protected int _outputHead = 0;

    /**
     * Pointer to the position right beyond the last character to output
     * (end marker; may be past the buffer)
     */
    protected int _outputTail = 0;

    /**
     * End marker of the output buffer; one past the last valid position
     * within the buffer.
     */
    protected int _outputEnd;

    /**
     * 6-char temporary buffer allocated if needed, for constructing
     * escape sequences
     */
    protected char[] _entityBuffer;

    /*
    ////////////////////////////////////////////////////
    // Life-cycle
    ////////////////////////////////////////////////////
     */

    public WriterBasedGenerator(IOContext ctxt, int features, ObjectCodec codec,
                                Writer w)
    {
        super(features, codec);
        _ioContext = ctxt;
        _writer = w;
        _outputBuffer = ctxt.allocConcatBuffer();
        _outputEnd = _outputBuffer.length;
    }

    /*
    ////////////////////////////////////////////////////
    // Output method implementations, structural
    ////////////////////////////////////////////////////
     */

    @Override
	protected void _writeStartArray()
        throws IOException, JsonGenerationException
    {
        if (_outputTail >= _outputEnd) {
            _flushBuffer();
        }
        _outputBuffer[_outputTail++] = '[';
    }

    @Override
    protected void _writeEndArray()
        throws IOException, JsonGenerationException
    {
        if (_outputTail >= _outputEnd) {
            _flushBuffer();
        }
        _outputBuffer[_outputTail++] = ']';
    }

    @Override
    protected void _writeStartObject()
        throws IOException, JsonGenerationException
    {
        if (_outputTail >= _outputEnd) {
            _flushBuffer();
        }
        _outputBuffer[_outputTail++] = '{';
    }

    @Override
    protected void _writeEndObject()
        throws IOException, JsonGenerationException
    {
        if (_outputTail >= _outputEnd) {
            _flushBuffer();
        }
        _outputBuffer[_outputTail++] = '}';
    }

    @Override
    protected void _writeFieldName(String name, boolean commaBefore)
        throws IOException, JsonGenerationException
    {
        if (_cfgPrettyPrinter != null) {
            _writePPFieldName(name, commaBefore);
            return;
        }
        // for fast+std case, need to output up to 2 chars, comma, dquote
        if ((_outputTail + 1) >= _outputEnd) {
            _flushBuffer();
        }
        if (commaBefore) {
            _outputBuffer[_outputTail++] = ',';
        }

        /* To support [JACKSON-46], we'll do this:
         * (Quostion: should quoting of spaces (etc) still be enabled?)
         */
        if (!isEnabled(Feature.QUOTE_FIELD_NAMES)) {
            _writeString(name);
            return;
        }

        // we know there's room for at least one more char
        _outputBuffer[_outputTail++] = '"';
        // The beef:
        _writeString(name);
        // and closing quotes; need room for one more char:
        if (_outputTail >= _outputEnd) {
            _flushBuffer();
        }
        _outputBuffer[_outputTail++] = '"';
    }

    /**
     * Specialized version of _writeFieldName, off-lined
     * to keep the "fast path" as simple (and hopefully fast) as possible.
     */
    protected final void _writePPFieldName(String name, boolean commaBefore)
        throws IOException, JsonGenerationException
    {
        if (commaBefore) {
            _cfgPrettyPrinter.writeObjectEntrySeparator(this);
        } else {
            _cfgPrettyPrinter.beforeObjectEntries(this);
        }

        if (isEnabled(Feature.QUOTE_FIELD_NAMES)) { // standard
            if (_outputTail >= _outputEnd) {
                _flushBuffer();
            }
            _outputBuffer[_outputTail++] = '"';
            _writeString(name);
            if (_outputTail >= _outputEnd) {
                _flushBuffer();
            }
            _outputBuffer[_outputTail++] = '"';
        } else { // non-standard, omit quotes
            _writeString(name);
        }
    }

    /*
    ////////////////////////////////////////////////////
    // Output method implementations, textual
    ////////////////////////////////////////////////////
     */

    @Override
    public void writeString(String text)
        throws IOException, JsonGenerationException
    {
        _verifyValueWrite("write text value");
        if (text == null) {
            _writeNull();
            return;
        }
        if (_outputTail >= _outputEnd) {
            _flushBuffer();
        }
        _outputBuffer[_outputTail++] = '"';
        _writeString(text);
        // And finally, closing quotes
        if (_outputTail >= _outputEnd) {
            _flushBuffer();
        }
        _outputBuffer[_outputTail++] = '"';
    }

    @Override
    public void writeString(char[] text, int offset, int len)
        throws IOException, JsonGenerationException
    {
        _verifyValueWrite("write text value");
        if (_outputTail >= _outputEnd) {
            _flushBuffer();
        }
        _outputBuffer[_outputTail++] = '"';
        _writeString(text, offset, len);
        // And finally, closing quotes
        if (_outputTail >= _outputEnd) {
            _flushBuffer();
        }
        _outputBuffer[_outputTail++] = '"';
    }

    /*
    ////////////////////////////////////////////////////
    // Output method implementations, unprocessed ("raw")
    ////////////////////////////////////////////////////
     */

    @Override
    public void writeRaw(String text)
        throws IOException, JsonGenerationException
    {
        // Nothing to check, can just output as is
        int len = text.length();
        int room = _outputEnd - _outputTail;

        if (room == 0) {
            _flushBuffer();
            room = _outputEnd - _outputTail;
        }
        // But would it nicely fit in? If yes, it's easy
        if (room >= len) {
            text.getChars(0, len, _outputBuffer, _outputTail);
            _outputTail += len;
        } else {
            writeRawLong(text);
        }
    }

    @Override
    public void writeRaw(String text, int start, int len)
        throws IOException, JsonGenerationException
    {
        // Nothing to check, can just output as is
        int room = _outputEnd - _outputTail;

        if (room < len) {
            _flushBuffer();
            room = _outputEnd - _outputTail;
        }
        // But would it nicely fit in? If yes, it's easy
        if (room >= len) {
            text.getChars(start, start+len, _outputBuffer, _outputTail);
            _outputTail += len;
        } else {            	
            writeRawLong(text.substring(start, start+len));
        }
    }

    @Override
    public void writeRaw(char[] text, int offset, int len)
        throws IOException, JsonGenerationException
    {
        // Only worth buffering if it's a short write?
        if (len < SHORT_WRITE) {
            int room = _outputEnd - _outputTail;
            if (len > room) {
                _flushBuffer();
            }
            System.arraycopy(text, offset, _outputBuffer, _outputTail, len);
            _outputTail += len;
            return;
        }
        // Otherwise, better just pass through:
        _flushBuffer();
        _writer.write(text, offset, len);
    }

    @Override
	public void writeRaw(char c)
        throws IOException, JsonGenerationException
    {
        if (_outputTail >= _outputEnd) {
            _flushBuffer();
        }
        _outputBuffer[_outputTail++] = c;
    }

    @Override
    public void writeRawValue(String text)
        throws IOException, JsonGenerationException
    {
        _verifyValueWrite("write raw value");
        writeRaw(text);
    }

    @Override
    public void writeRawValue(String text, int offset, int len)
        throws IOException, JsonGenerationException
    {
        _verifyValueWrite("write raw value");
        writeRaw(text, offset, len);
    }

    @Override
    public void writeRawValue(char[] text, int offset, int len)
        throws IOException, JsonGenerationException
    {
        _verifyValueWrite("write raw value");
        writeRaw(text, offset, len);
    }

    private void writeRawLong(String text)
        throws IOException, JsonGenerationException
    {
        int room = _outputEnd - _outputTail;
        // If not, need to do it by looping
        text.getChars(0, room, _outputBuffer, _outputTail);
        _outputTail += room;
        _flushBuffer();
        int offset = room;
        int len = text.length() - room;

        while (len > _outputEnd) {
            int amount = _outputEnd;
            text.getChars(offset, offset+amount, _outputBuffer, 0);
            _outputHead = 0;
            _outputTail = amount;
            _flushBuffer();
            offset += amount;
            len -= amount;
        }
        // And last piece (at most length of buffer)
        text.getChars(offset, offset+len, _outputBuffer, 0);
        _outputHead = 0;
        _outputTail = len;
    }

    /*
    ////////////////////////////////////////////////////
    // Output method implementations, base64-encoded binary
    ////////////////////////////////////////////////////
     */

    @Override
    public void writeBinary(Base64Variant b64variant, byte[] data, int offset, int len)
        throws IOException, JsonGenerationException
    {
        _verifyValueWrite("write binary value");
        // Starting quotes
        if (_outputTail >= _outputEnd) {
            _flushBuffer();
        }
        _outputBuffer[_outputTail++] = '"';
        _writeBinary(b64variant, data, offset, offset+len);
        // and closing quotes
        if (_outputTail >= _outputEnd) {
            _flushBuffer();
        }
        _outputBuffer[_outputTail++] = '"';
    }

    /*
    ////////////////////////////////////////////////////
    // Output method implementations, primitive
    ////////////////////////////////////////////////////
     */

    @Override
    public void writeNumber(int i)
        throws IOException, JsonGenerationException
    {
        _verifyValueWrite("write number");
        // up to 10 digits and possible minus sign
        if ((_outputTail + 11) >= _outputEnd) {
            _flushBuffer();
        }
        if (_cfgNumbersAsStrings) {
            _writeQuotedInt(i);
            return;
        }
        _outputTail = NumberOutput.outputInt(i, _outputBuffer, _outputTail);
    }

    private final void _writeQuotedInt(int i) throws IOException {
        if ((_outputTail + 13) >= _outputEnd) {
            _flushBuffer();
        }
        _outputBuffer[_outputTail++] = '"';
        _outputTail = NumberOutput.outputInt(i, _outputBuffer, _outputTail);
        _outputBuffer[_outputTail++] = '"';
    }    

    @Override
    public void writeNumber(long l)
        throws IOException, JsonGenerationException
    {
        _verifyValueWrite("write number");
        if (_cfgNumbersAsStrings) {
            _writeQuotedLong(l);
            return;
        }
        if ((_outputTail + 21) >= _outputEnd) {
            // up to 20 digits, minus sign
            _flushBuffer();
        }
        _outputTail = NumberOutput.outputLong(l, _outputBuffer, _outputTail);
    }

    private final void _writeQuotedLong(long l) throws IOException {
        if ((_outputTail + 23) >= _outputEnd) {
            _flushBuffer();
        }
        _outputBuffer[_outputTail++] = '"';
        _outputTail = NumberOutput.outputLong(l, _outputBuffer, _outputTail);
        _outputBuffer[_outputTail++] = '"';
    }

    // !!! 05-Aug-2008, tatus: Any ways to optimize these?

    @Override
    public void writeNumber(BigInteger value)
        throws IOException, JsonGenerationException
    {
        _verifyValueWrite("write number");
        if (value == null) {
            _writeNull();
        } else if (_cfgNumbersAsStrings) {
            _writeQuotedRaw(value);
        } else {
            writeRaw(value.toString());
        }
    }

    
    @Override
    public void writeNumber(double d)
        throws IOException, JsonGenerationException
    {
        if (_cfgNumbersAsStrings ||
            // [JACKSON-139]
            (((Double.isNaN(d) || Double.isInfinite(d))
                && isEnabled(Feature.QUOTE_NON_NUMERIC_NUMBERS)))) {
            writeString(String.valueOf(d));
            return;
        }
        // What is the max length for doubles? 40 chars?
        _verifyValueWrite("write number");
        writeRaw(String.valueOf(d));
    }

    @Override
    public void writeNumber(float f)
        throws IOException, JsonGenerationException
    {
        if (_cfgNumbersAsStrings ||
            // [JACKSON-139]
            (((Float.isNaN(f) || Float.isInfinite(f))
                && isEnabled(Feature.QUOTE_NON_NUMERIC_NUMBERS)))) {
            writeString(String.valueOf(f));
            return;
        }
        // What is the max length for floats?
        _verifyValueWrite("write number");
        writeRaw(String.valueOf(f));
    }

    @Override
    public void writeNumber(BigDecimal value)
        throws IOException, JsonGenerationException
    {
        // Don't really know max length for big decimal, no point checking
        _verifyValueWrite("write number");
        if (value == null) {
            _writeNull();
        } else if (_cfgNumbersAsStrings) {
            _writeQuotedRaw(value);
        } else {
            writeRaw(value.toString());
        }
    }

    @Override
    public void writeNumber(String encodedValue)
        throws IOException, JsonGenerationException
    {
        _verifyValueWrite("write number");
        if (_cfgNumbersAsStrings) {
            _writeQuotedRaw(encodedValue);            
        } else {
            writeRaw(encodedValue);
        }
    }

    private final void _writeQuotedRaw(Object value) throws IOException
    {
        if (_outputTail >= _outputEnd) {
            _flushBuffer();
        }
        _outputBuffer[_outputTail++] = '"';
        writeRaw(value.toString());
        if (_outputTail >= _outputEnd) {
            _flushBuffer();
        }
        _outputBuffer[_outputTail++] = '"';
    }
    
    @Override
    public void writeBoolean(boolean state)
        throws IOException, JsonGenerationException
    {
        _verifyValueWrite("write boolean value");
        if ((_outputTail + 5) >= _outputEnd) {
            _flushBuffer();
        }
        int ptr = _outputTail;
        char[] buf = _outputBuffer;
        if (state) {
            buf[ptr] = 't';
            buf[++ptr] = 'r';
            buf[++ptr] = 'u';
            buf[++ptr] = 'e';
        } else {
            buf[ptr] = 'f';
            buf[++ptr] = 'a';
            buf[++ptr] = 'l';
            buf[++ptr] = 's';
            buf[++ptr] = 'e';
        }
        _outputTail = ptr+1;
    }

    @Override
    public void writeNull()
        throws IOException, JsonGenerationException
    {
        _verifyValueWrite("write null value");
        _writeNull();
    }

    /*
    ////////////////////////////////////////////////////
    // Implementations for other methods
    ////////////////////////////////////////////////////
     */

    @Override
    protected final void _verifyValueWrite(String typeMsg)
        throws IOException, JsonGenerationException
    {
        int status = _writeContext.writeValue();
        if (status == JsonWriteContext.STATUS_EXPECT_NAME) {
            _reportError("Can not "+typeMsg+", expecting field name");
        }
        if (_cfgPrettyPrinter == null) {
            char c;
            switch (status) {
            case JsonWriteContext.STATUS_OK_AFTER_COMMA:
                c = ',';
                break;
            case JsonWriteContext.STATUS_OK_AFTER_COLON:
                c = ':';
                break;
            case JsonWriteContext.STATUS_OK_AFTER_SPACE:
                c = ' ';
                break;
            case JsonWriteContext.STATUS_OK_AS_IS:
            default:
                return;
            }
            if (_outputTail >= _outputEnd) {
                _flushBuffer();
            }
            _outputBuffer[_outputTail] = c;
            ++_outputTail;
            return;
        }
        // Otherwise, pretty printer knows what to do...
        _verifyPrettyValueWrite(typeMsg, status);
    }

    protected final void _verifyPrettyValueWrite(String typeMsg, int status)
        throws IOException, JsonGenerationException
    {
        // If we have a pretty printer, it knows what to do:
        switch (status) {
        case JsonWriteContext.STATUS_OK_AFTER_COMMA: // array
            _cfgPrettyPrinter.writeArrayValueSeparator(this);
            break;
        case JsonWriteContext.STATUS_OK_AFTER_COLON:
            _cfgPrettyPrinter.writeObjectFieldValueSeparator(this);
            break;
        case JsonWriteContext.STATUS_OK_AFTER_SPACE:
            _cfgPrettyPrinter.writeRootValueSeparator(this);
            break;
        case JsonWriteContext.STATUS_OK_AS_IS:
            // First entry, but of which context?
            if (_writeContext.inArray()) {
                _cfgPrettyPrinter.beforeArrayValues(this);
            } else if (_writeContext.inObject()) {
                _cfgPrettyPrinter.beforeObjectEntries(this);
            }
            break;
        default:
            _cantHappen();
            break;
        }
    }

    /*
    ////////////////////////////////////////////////////
    // Low-level output handling
    ////////////////////////////////////////////////////
     */

    @Override
    public final void flush()
        throws IOException
    {
        _flushBuffer();
        _writer.flush();
    }

    @Override
    public void close()
        throws IOException
    {
        super.close();

        /* 05-Dec-2008, tatu: To add [JACKSON-27], need to close open
         *   scopes.
         */
        // First: let's see that we still have buffers...
        if (_outputBuffer != null
            && isEnabled(Feature.AUTO_CLOSE_JSON_CONTENT)) {
            while (true) {
                JsonStreamContext ctxt = getOutputContext();
                if (ctxt.inArray()) {
                    writeEndArray();
                } else if (ctxt.inObject()) {
                    writeEndObject();
                } else {
                    break;
                }
            }
        }
        _flushBuffer();

        /* 25-Nov-2008, tatus: As per [JACKSON-16] we are not to call close()
         *   on the underlying Reader, unless we "own" it, or auto-closing
         *   feature is enabled.
         *   One downside: when using UTF8Writer, underlying buffer(s)
         *   may not be properly recycled if we don't close the writer.
         */
        if (_ioContext.isResourceManaged() || isEnabled(Feature.AUTO_CLOSE_TARGET)) {
            _writer.close();
        } else {
            // If we can't close it, we should at least flush
            _writer.flush();
        }
        // Internal buffer(s) generator has can now be released as well
        _releaseBuffers();
    }

    @Override
    protected void _releaseBuffers()
    {
        char[] buf = _outputBuffer;
        if (buf != null) {
            _outputBuffer = null;
            _ioContext.releaseConcatBuffer(buf);
        }
    }

    /*
    ////////////////////////////////////////////////////
    // Internal methods, low-level writing
    ////////////////////////////////////////////////////
     */

    private void _writeString(String text)
        throws IOException, JsonGenerationException
    {
        /* One check first: if String won't fit in the buffer, let's
         * segment writes. No point in extending buffer to huge sizes
         * (like if someone wants to include multi-megabyte base64
         * encoded stuff or such)
         */
        int len = text.length();
        if (len > _outputEnd) { // Let's reserve space for entity at begin/end
            _writeLongString(text);
            return;
        }

        // Ok: we know String will fit in buffer ok
        // But do we need to flush first?
        if ((_outputTail + len) > _outputEnd) {
            _flushBuffer();
        }
        text.getChars(0, len, _outputBuffer, _outputTail);

        // And then we'll need to verify need for escaping etc:
        int end = _outputTail + len;
        final int[] escCodes = CharTypes.getOutputEscapes();
        final int escLen = escCodes.length;

        output_loop:
        while (_outputTail < end) {
            // Fast loop for chars not needing escaping
            escape_loop:
            while (true) {
                char c = _outputBuffer[_outputTail];
                if (c < escLen && escCodes[c] != 0) {
                    break escape_loop;
                }
                if (++_outputTail >= end) {
                    break output_loop;
                }
            }

            // Ok, bumped into something that needs escaping.
            /* First things first: need to flush the buffer.
             * Inlined, as we don't want to lose tail pointer
             */
            int flushLen = (_outputTail - _outputHead);
            if (flushLen > 0) {
                _writer.write(_outputBuffer, _outputHead, flushLen);
            }
            /* In any case, tail will be the new start, so hopefully
             * we have room now.
             */
            {
                int escCode = escCodes[_outputBuffer[_outputTail]];
                ++_outputTail;
                int needLen = (escCode < 0) ? 6 : 2;
                // If not, need to call separate method (note: buffer is empty now)
                if (needLen > _outputTail) {
                    _outputHead = _outputTail;
                    _writeSingleEscape(escCode);
                } else {
                    // But if it fits, can just prepend to buffer
                    int ptr = _outputTail - needLen;
                    _outputHead = ptr;
                    _appendSingleEscape(escCode, _outputBuffer, ptr);
                }
            }
        }
    }

    /**
     * Method called to write "long strings", strings whose length exceeds
     * output buffer length.
     */
    private void _writeLongString(String text)
        throws IOException, JsonGenerationException
    {
        // First things first: let's flush the buffer to get some more room
        _flushBuffer();

        // Then we can write 
        final int textLen = text.length();
        int offset = 0;
        do {
            int max = _outputEnd;
            int segmentLen = ((offset + max) > textLen)
                ? (textLen - offset) : max;
            text.getChars(offset, offset+segmentLen, _outputBuffer, 0);
            _writeSegment(segmentLen);
            offset += segmentLen;
        } while (offset < textLen);
    }
    /**
     * Method called to output textual context which has been copied
     * to the output buffer prior to call. If any escaping is needed,
     * it will also be handled by the method.
     *

* Note: when called, textual content to write is within output * buffer, right after buffered content (if any). That's why only * length of that text is passed, as buffer and offset are implied. */ private final void _writeSegment(int end) throws IOException, JsonGenerationException { final int[] escCodes = CharTypes.getOutputEscapes(); final int escLen = escCodes.length; int ptr = 0; output_loop: while (ptr < end) { // Fast loop for chars not needing escaping int start = ptr; while (true) { char c = _outputBuffer[ptr]; if (c < escLen && escCodes[c] != 0) { break; } if (++ptr >= end) { break; } } // Ok, bumped into something that needs escaping. /* First things first: need to flush the buffer. * Inlined, as we don't want to lose tail pointer */ int flushLen = (ptr - start); if (flushLen > 0) { _writer.write(_outputBuffer, start, flushLen); if (ptr >= end) { break output_loop; } } /* In any case, tail will be the new start, so hopefully * we have room now. */ { int escCode = escCodes[_outputBuffer[ptr]]; ++ptr; int needLen = (escCode < 0) ? 6 : 2; // If not, need to call separate method (note: buffer is empty now) if (needLen > _outputTail) { _writeSingleEscape(escCode); } else { // But if it fits, can just prepend to buffer ptr -= needLen; _appendSingleEscape(escCode, _outputBuffer, ptr); } } } } /** * This method called when the string content is already in * a char buffer, and need not be copied for processing. */ private void _writeString(char[] text, int offset, int len) throws IOException, JsonGenerationException { /* Let's just find longest spans of non-escapable * content, and for each see if it makes sense * to copy them, or write through */ len += offset; // -> len marks the end from now on final int[] escCodes = CharTypes.getOutputEscapes(); final int escLen = escCodes.length; while (offset < len) { int start = offset; while (true) { char c = text[offset]; if (c < escLen && escCodes[c] != 0) { break; } if (++offset >= len) { break; } } // Short span? Better just copy it to buffer first: int newAmount = offset - start; if (newAmount < SHORT_WRITE) { // Note: let's reserve room for escaped char (up to 6 chars) if ((_outputTail + newAmount) > _outputEnd) { _flushBuffer(); } if (newAmount > 0) { System.arraycopy(text, start, _outputBuffer, _outputTail, newAmount); _outputTail += newAmount; } } else { // Nope: better just write through _flushBuffer(); _writer.write(text, start, newAmount); } // Was this the end? if (offset >= len) { // yup break; } // Nope, need to escape the char. int escCode = escCodes[text[offset]]; ++offset; int needLen = (escCode < 0) ? 6 : 2; if ((_outputTail + needLen) > _outputEnd) { _flushBuffer(); } _appendSingleEscape(escCode, _outputBuffer, _outputTail); _outputTail += needLen; } } protected void _writeBinary(Base64Variant b64variant, byte[] input, int inputPtr, final int inputEnd) throws IOException, JsonGenerationException { // Encoding is by chunks of 3 input, 4 output chars, so: int safeInputEnd = inputEnd - 3; // Let's also reserve room for possible (and quoted) lf char each round int safeOutputEnd = _outputEnd - 6; int chunksBeforeLF = b64variant.getMaxLineLength() >> 2; // Ok, first we loop through all full triplets of data: while (inputPtr <= safeInputEnd) { if (_outputTail > safeOutputEnd) { // need to flush _flushBuffer(); } // First, mash 3 bytes into lsb of 32-bit int int b24 = ((int) input[inputPtr++]) << 8; b24 |= ((int) input[inputPtr++]) & 0xFF; b24 = (b24 << 8) | (((int) input[inputPtr++]) & 0xFF); _outputTail = b64variant.encodeBase64Chunk(b24, _outputBuffer, _outputTail); if (--chunksBeforeLF <= 0) { // note: must quote in JSON value _outputBuffer[_outputTail++] = '\\'; _outputBuffer[_outputTail++] = 'n'; chunksBeforeLF = b64variant.getMaxLineLength() >> 2; } } // And then we may have 1 or 2 leftover bytes to encode int inputLeft = inputEnd - inputPtr; // 0, 1 or 2 if (inputLeft > 0) { // yes, but do we have room for output? if (_outputTail > safeOutputEnd) { // don't really need 6 bytes but... _flushBuffer(); } int b24 = ((int) input[inputPtr++]) << 16; if (inputLeft == 2) { b24 |= (((int) input[inputPtr++]) & 0xFF) << 8; } _outputTail = b64variant.encodeBase64Partial(b24, inputLeft, _outputBuffer, _outputTail); } } private final void _writeNull() throws IOException { if ((_outputTail + 4) >= _outputEnd) { _flushBuffer(); } int ptr = _outputTail; char[] buf = _outputBuffer; buf[ptr] = 'n'; buf[++ptr] = 'u'; buf[++ptr] = 'l'; buf[++ptr] = 'l'; _outputTail = ptr+1; } /** * @param escCode Character code for escape sequence (\C); or -1 * to indicate a generic (\\uXXXX) sequence. */ private void _writeSingleEscape(int escCode) throws IOException { char[] buf = _entityBuffer; if (buf == null) { buf = new char[6]; buf[0] = '\\'; buf[2] = '0'; buf[3] = '0'; } if (escCode < 0) { // control char, value -(char + 1) int value = -(escCode + 1); buf[1] = 'u'; // We know it's a control char, so only the last 2 chars are non-0 buf[4] = HEX_CHARS[value >> 4]; buf[5] = HEX_CHARS[value & 0xF]; _writer.write(buf, 0, 6); } else { buf[1] = (char) escCode; _writer.write(buf, 0, 2); } } private void _appendSingleEscape(int escCode, char[] buf, int ptr) { if (escCode < 0) { // control char, value -(char + 1) int value = -(escCode + 1); buf[ptr] = '\\'; buf[++ptr] = 'u'; // We know it's a control char, so only the last 2 chars are non-0 buf[++ptr] = '0'; buf[++ptr] = '0'; buf[++ptr] = HEX_CHARS[value >> 4]; buf[++ptr] = HEX_CHARS[value & 0xF]; } else { buf[ptr] = '\\'; buf[ptr+1] = (char) escCode; } } protected final void _flushBuffer() throws IOException { int len = _outputTail - _outputHead; if (len > 0) { int offset = _outputHead; _outputTail = _outputHead = 0; _writer.write(_outputBuffer, offset, len); } } }





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