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 * 
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
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 *************************************************************/


package com.sun.star.lib.uno.adapter;

import java.io.IOException;
import com.sun.star.io.XInputStream;
import java.io.InputStream;

/**	The <code>InputStreamToInputXStreamAdapter</code> wraps the 
	Java <code>InputStream</code> object into a 
	UNO <code>XInputStream</code> object.  
	This allows users to access an <code>InputStream</code> 
	as if it were an <code>XInputStream</code>.
 */
public class InputStreamToXInputStreamAdapter implements XInputStream {

    /** 
     *  Internal store to the InputStream
     */
    private InputStream iIn;
 
    /**
     *  Constructor.
     *
     *  @param  in  The <code>XInputStream</code> to be 
     *              accessed as an <code>InputStream</code>.
     */
    public InputStreamToXInputStreamAdapter (InputStream in) 
	{
        iIn = in;
    }

    public int available() throws 
			com.sun.star.io.IOException
	{

        int bytesAvail;

        try {
            bytesAvail = iIn.available();
        } catch (IOException e) {
            throw new com.sun.star.io.IOException(e.toString());
        }

        return(bytesAvail);
    }

    public void closeInput() throws 
			com.sun.star.io.IOException 
	{
        try {
            iIn.close();
        } catch (IOException e) {
            throw new com.sun.star.io.IOException(e.toString());
        }
    }

    public int readBytes(byte[][] b, int len) throws 
			com.sun.star.io.IOException 
	{
        int count = 0;
        try {
	    long bytesRead=0;
            int totalBytesRead = 0;
            if (b[0] == null || b[0].length < len) {
                b[0] = new byte[len];
            }
            // Casting bytesRead to an int is okay, since the user can
            // only pass in an integer length to read, so the bytesRead 
            // must <= len.
            //
            while ((len > 0) && ((bytesRead = iIn.read(b[0], totalBytesRead, len)) > 0)) {
                totalBytesRead += (int)bytesRead;
                len -= (int)bytesRead;
            }
            if (totalBytesRead < b[0].length) {
                byte[] out = new byte[totalBytesRead];
                System.arraycopy(b[0], 0, out, 0, totalBytesRead);
                b[0] = out;
            }
	    return totalBytesRead;
	    
		
        } catch (IOException e) {
            throw new com.sun.star.io.IOException("reader error: "+e.toString());
        }
    }

    public int readSomeBytes(byte[][] b, int len) throws 
			com.sun.star.io.IOException 
	{
        int count = 0;
        try {
	    long bytesRead=0;
            if (b[0] == null || b[0].length < len) {
                b[0] = new byte[len];
            }
	    if (len >iIn.available()) {
			bytesRead = iIn.read(b[0], 0, iIn.available());
	    }
	    else{
			bytesRead = iIn.read(b[0], 0, len);
	    }
            // Casting bytesRead to an int is okay, since the user can
            // only pass in an integer length to read, so the bytesRead 
            // must <= len.
            //
            if (bytesRead < b[0].length) {
                int outSize = bytesRead > 0 ? (int)bytesRead : 0;
                byte[] out = new byte[outSize];
                System.arraycopy(b[0], 0, out, 0, outSize);
                b[0] = out;
            }
            if (bytesRead <= 0) {
                return(0);
	    } 	    
	    return ((int)bytesRead);
	    
		
        } catch (IOException e) {
            throw new com.sun.star.io.IOException("reader error: "+e.toString());
        }
    }

    public void skipBytes(int n) throws 
			com.sun.star.io.IOException 
	{
        int avail;
        int tmpLongVal = n;
        int  tmpIntVal;

        try {
            avail = iIn.available();
        } catch (IOException e) {
            throw new com.sun.star.io.IOException(e.toString());
        }

        do {
            if (tmpLongVal >= Integer.MAX_VALUE) {
               tmpIntVal = Integer.MAX_VALUE;
            } else {
               // Casting is safe here.
               tmpIntVal = (int)tmpLongVal;
            }
            tmpLongVal -= tmpIntVal;
 
            try {
                iIn.skip(tmpIntVal);
            } catch (IOException e) {
                throw new com.sun.star.io.IOException(e.toString());
            }
        } while (tmpLongVal > 0);
    }
}