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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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package com.sun.xml.internal.bind.v2.runtime.unmarshaller;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

import javax.activation.DataHandler;
import javax.activation.DataSource;
import javax.xml.stream.XMLStreamException;

import javax.xml.stream.XMLStreamWriter;

import com.sun.xml.internal.bind.DatatypeConverterImpl;
import com.sun.xml.internal.bind.v2.runtime.XMLSerializer;
import com.sun.xml.internal.bind.v2.runtime.output.Pcdata;
import com.sun.xml.internal.bind.v2.runtime.output.UTF8XmlOutput;
import com.sun.xml.internal.bind.v2.util.ByteArrayOutputStreamEx;
import com.sun.istack.internal.Nullable;


Fed to unmarshaller when the 'text' data is actually
a virtual image of base64 encoding of the binary data
transferred on the wire.
Used for the MTOM support.
This object is mutable and the owner of this object can
reuse it with new data.
Also used by the marshaller to write out the binary data
that could be possibly attached.

Author:Kohsuke Kawaguchi, Martin Grebac
See Also:
/**
 * Fed to unmarshaller when the 'text' data is actually
 * a virtual image of base64 encoding of the binary data
 * transferred on the wire.
 *
 * Used for the MTOM support.
 *
 * This object is mutable and the owner of this object can
 * reuse it with new data.
 *
 * Also used by the marshaller to write out the binary data
 * that could be possibly attached.
 *
 * @see XmlVisitor#text(CharSequence)
 * @see XMLSerializer#text(Pcdata,String)
 *
 * @author Kohsuke Kawaguchi, Martin Grebac
 */
public final class Base64Data extends Pcdata {

    // either dataHandler or (data,dataLen,mimeType?) must be present
    private DataHandler dataHandler;
    private byte[] data;
    
Length of the valid data in data. 
/**
     * Length of the valid data in {@link #data}.
     */
    private int dataLen;
    
Optional MIME type of data. Unused when dataHandler is set. Use DataHandler.getContentType() in that case. 
/**
     * Optional MIME type of {@link #data}.
     *
     * Unused when {@link #dataHandler} is set.
     * Use {@link DataHandler#getContentType()} in that case.
     */
    private @Nullable
    String mimeType;

    
Fills in the data object by a portion of the byte[].

Params:
  • len – 
     data[0] to data[len-1] are treated as the data.
/**
     * Fills in the data object by a portion of the byte[].
     *
     * @param len
     *      data[0] to data[len-1] are treated as the data.
     */
    public void set(byte[] data, int len, @Nullable String mimeType) {
        this.data = data;
        this.dataLen = len;
        this.dataHandler = null;
        this.mimeType = mimeType;
    }

    
Fills in the data object by the byte[] of the exact length.

Params:
  • data – 
     this buffer may be owned directly by the unmarshaleld JAXB object.
/**
     * Fills in the data object by the byte[] of the exact length.
     *
     * @param data
     *      this buffer may be owned directly by the unmarshaleld JAXB object.
     */
    public void set(byte[] data, @Nullable String mimeType) {
        set(data, data.length, mimeType);
    }

    
Fills in the data object by a DataHandler. 
/**
     * Fills in the data object by a {@link DataHandler}.
     */
    public void set(DataHandler data) {
        assert data != null;
        this.dataHandler = data;
        this.data = null;
    }

    
Gets the raw data.

/**
     * Gets the raw data.
     */
    public DataHandler getDataHandler() {
        if (dataHandler == null) {
            dataHandler = new DataHandler(new DataSource() {

                public String getContentType() {
                    return getMimeType();
                }

                public InputStream getInputStream() {
                    return new ByteArrayInputStream(data, 0, dataLen);
                }

                public String getName() {
                    return null;
                }

                public OutputStream getOutputStream() {
                    throw new UnsupportedOperationException();
                }
            });
        }

        return dataHandler;
    }

    
Gets the byte[] of the exact length.

/**
     * Gets the byte[] of the exact length.
     */
    public byte[] getExact() {
        get();
        if (dataLen != data.length) {
            byte[] buf = new byte[dataLen];
            System.arraycopy(data, 0, buf, 0, dataLen);
            data = buf;
        }
        return data;
    }

    
Gets the data as an InputStream. 
/**
     * Gets the data as an {@link InputStream}.
     */
    public InputStream getInputStream() throws IOException {
        if (dataHandler != null) {
            return dataHandler.getInputStream();
        } else {
            return new ByteArrayInputStream(data, 0, dataLen);
        }
    }

    
Returns false if this object only has DataHandler and therefore get() operation is likely going to be expensive. 
/**
     * Returns false if this object only has {@link DataHandler} and therefore
     * {@link #get()} operation is likely going to be expensive.
     */
    public boolean hasData() {
        return data != null;
    }

    
Gets the raw data. The size of the byte array maybe larger than the actual length.

/**
     * Gets the raw data. The size of the byte array maybe larger than the actual length.
     */
    public byte[] get() {
        if (data == null) {
            try {
                ByteArrayOutputStreamEx baos = new ByteArrayOutputStreamEx(1024);
                InputStream is = dataHandler.getDataSource().getInputStream();
                baos.readFrom(is);
                is.close();
                data = baos.getBuffer();
                dataLen = baos.size();
            } catch (IOException e) {
                // TODO: report the error to the unmarshaller
                dataLen = 0;    // recover by assuming length-0 data
            }
        }
        return data;
    }

    public int getDataLen() {
        return dataLen;
    }

    public String getMimeType() {
        if (mimeType == null) {
            return "application/octet-stream";
        }
        return mimeType;
    }

    
Gets the number of characters needed to represent
this binary data in the base64 encoding.

/**
     * Gets the number of characters needed to represent
     * this binary data in the base64 encoding.
     */
    public int length() {
        // for each 3 bytes you use 4 chars
        // if the remainder is 1 or 2 there will be 4 more
        get();  // fill in the buffer if necessary
        return ((dataLen + 2) / 3) * 4;
    }

    
Encode this binary data in the base64 encoding
and returns the character at the specified position.

/**
     * Encode this binary data in the base64 encoding
     * and returns the character at the specified position.
     */
    public char charAt(int index) {
        // we assume that the length() method is called before this method
        // (otherwise how would the caller know that the index is valid?)
        // so we assume that the byte[] is already populated

        int offset = index % 4;
        int base = (index / 4) * 3;

        byte b1, b2;

        switch (offset) {
            case 0:
                return DatatypeConverterImpl.encode(data[base] >> 2);
            case 1:
                if (base + 1 < dataLen) {
                    b1 = data[base + 1];
                } else {
                    b1 = 0;
                }
                return DatatypeConverterImpl.encode(
                        ((data[base] & 0x3) << 4)
                        | ((b1 >> 4) & 0xF));
            case 2:
                if (base + 1 < dataLen) {
                    b1 = data[base + 1];
                    if (base + 2 < dataLen) {
                        b2 = data[base + 2];
                    } else {
                        b2 = 0;
                    }

                    return DatatypeConverterImpl.encode(
                            ((b1 & 0xF) << 2)
                            | ((b2 >> 6) & 0x3));
                } else {
                    return '=';
                }
            case 3:
                if (base + 2 < dataLen) {
                    return DatatypeConverterImpl.encode(data[base + 2] & 0x3F);
                } else {
                    return '=';
                }
        }

        throw new IllegalStateException();
    }

    
Internally this is only used to split a text to a list,
which doesn't happen that much for base64.
So this method should be smaller than faster.

/**
     * Internally this is only used to split a text to a list,
     * which doesn't happen that much for base64.
     * So this method should be smaller than faster.
     */
    public CharSequence subSequence(int start, int end) {
        StringBuilder buf = new StringBuilder();
        get();  // fill in the buffer if we haven't done so
        for (int i = start; i < end; i++) {
            buf.append(charAt(i));
        }
        return buf;
    }

    
Returns the base64 encoded string of this data.

/**
     * Returns the base64 encoded string of this data.
     */
    public String toString() {
        get();  // fill in the buffer
        return DatatypeConverterImpl._printBase64Binary(data, 0, dataLen);
    }

    @Override
    public void writeTo(char[] buf, int start) {
        get();
        DatatypeConverterImpl._printBase64Binary(data, 0, dataLen, buf, start);
    }

    public void writeTo(UTF8XmlOutput output) throws IOException {
        // TODO: this is inefficient if the data source is note byte[] but DataHandler
        get();
        output.text(data, dataLen);
    }

    public void writeTo(XMLStreamWriter output) throws IOException, XMLStreamException {
        get();
        DatatypeConverterImpl._printBase64Binary(data, 0, dataLen, output);
    }

}