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Spring Cloud Contract Shaded Dependencies
package shaded.shaded.org.eclipse.aether.spi.connector.transport;
/*
* 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
* under the License.
*/
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.net.URI;
import java.nio.charset.StandardCharsets;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
/**
* A task to download a resource from the remote repository.
*
* @see Transporter#get(GetTask)
*/
public final class GetTask
extends TransportTask
{
private File dataFile;
private boolean resume;
private ByteArrayOutputStream dataBytes;
private Map checksums;
/**
* Creates a new task for the specified remote resource.
*
* @param location The relative location of the resource in the remote repository, must not be {@code null}.
*/
public GetTask( URI location )
{
checksums = Collections.emptyMap();
setLocation( location );
}
/**
* Opens an output stream to store the downloaded data. Depending on {@link #getDataFile()}, this stream writes
* either to a file on disk or a growable buffer in memory. It's the responsibility of the caller to close the
* provided stream.
*
* @return The output stream for the data, never {@code null}. The stream is unbuffered.
* @throws IOException If the stream could not be opened.
*/
public OutputStream newOutputStream()
throws IOException
{
return newOutputStream( false );
}
/**
* Opens an output stream to store the downloaded data. Depending on {@link #getDataFile()}, this stream writes
* either to a file on disk or a growable buffer in memory. It's the responsibility of the caller to close the
* provided stream.
*
* @param resume {@code true} if the download resumes from the byte offset given by {@link #getResumeOffset()},
* {@code false} if the download starts at the first byte of the resource.
* @return The output stream for the data, never {@code null}. The stream is unbuffered.
* @throws IOException If the stream could not be opened.
*/
public OutputStream newOutputStream( boolean resume )
throws IOException
{
if ( dataFile != null )
{
return new FileOutputStream( dataFile, this.resume && resume );
}
if ( dataBytes == null )
{
dataBytes = new ByteArrayOutputStream( 1024 );
}
else if ( !resume )
{
dataBytes.reset();
}
return dataBytes;
}
/**
* Gets the file (if any) where the downloaded data should be stored. If the specified file already exists, it will
* be overwritten.
*
* @return The data file or {@code null} if the data will be buffered in memory.
*/
public File getDataFile()
{
return dataFile;
}
/**
* Sets the file where the downloaded data should be stored. If the specified file already exists, it will be
* overwritten. Unless the caller can reasonably expect the resource to be small, use of a data file is strongly
* recommended to avoid exhausting heap memory during the download.
*
* @param dataFile The file to store the downloaded data, may be {@code null} to store the data in memory.
* @return This task for chaining, never {@code null}.
*/
public GetTask setDataFile( File dataFile )
{
return setDataFile( dataFile, false );
}
/**
* Sets the file where the downloaded data should be stored. If the specified file already exists, it will be
* overwritten or appended to, depending on the {@code resume} argument and the capabilities of the transporter.
* Unless the caller can reasonably expect the resource to be small, use of a data file is strongly recommended to
* avoid exhausting heap memory during the download.
*
* @param dataFile The file to store the downloaded data, may be {@code null} to store the data in memory.
* @param resume {@code true} to request resuming a previous download attempt, starting from the current length of
* the data file, {@code false} to download the resource from its beginning.
* @return This task for chaining, never {@code null}.
*/
public GetTask setDataFile( File dataFile, boolean resume )
{
this.dataFile = dataFile;
this.resume = resume;
return this;
}
/**
* Gets the byte offset within the resource from which the download should resume if supported.
*
* @return The zero-based index of the first byte to download or {@code 0} for a full download from the start of the
* resource, never negative.
*/
public long getResumeOffset()
{
if ( resume )
{
if ( dataFile != null )
{
return dataFile.length();
}
if ( dataBytes != null )
{
return dataBytes.size();
}
}
return 0;
}
/**
* Gets the data that was downloaded into memory. Note: This method may only be called if
* {@link #getDataFile()} is {@code null} as otherwise the downloaded data has been written directly to disk.
*
* @return The possibly empty data bytes, never {@code null}.
*/
public byte[] getDataBytes()
{
if ( dataFile != null || dataBytes == null )
{
return EMPTY;
}
return dataBytes.toByteArray();
}
/**
* Gets the data that was downloaded into memory as a string. The downloaded data is assumed to be encoded using
* UTF-8. Note: This method may only be called if {@link #getDataFile()} is {@code null} as
* otherwise the downloaded data has been written directly to disk.
*
* @return The possibly empty data string, never {@code null}.
*/
public String getDataString()
{
if ( dataFile != null || dataBytes == null )
{
return "";
}
return new String( dataBytes.toByteArray(), StandardCharsets.UTF_8 );
}
/**
* Sets the listener that is to be notified during the transfer.
*
* @param listener The listener to notify of progress, may be {@code null}.
* @return This task for chaining, never {@code null}.
*/
public GetTask setListener( TransportListener listener )
{
super.setListener( listener );
return this;
}
/**
* Gets the checksums which the remote repository advertises for the resource. The map is keyed by algorithm name
* (cf. {@link java.security.MessageDigest#getInstance(String)}) and the values are hexadecimal representations of
* the corresponding value. Note: This is optional data that a transporter may return if the underlying
* transport protocol provides metadata (e.g. HTTP headers) along with the actual resource data.
*
* @return The (read-only) checksums advertised for the downloaded resource, possibly empty but never {@code null}.
*/
public Map getChecksums()
{
return checksums;
}
/**
* Sets a checksum which the remote repository advertises for the resource. Note: Transporters should only
* use this method to record checksum information which is readily available while performing the actual download,
* they should not perform additional transfers to gather this data.
*
* @param algorithm The name of the checksum algorithm (e.g. {@code "SHA-1"}, cf.
* {@link java.security.MessageDigest#getInstance(String)} ), may be {@code null}.
* @param value The hexadecimal representation of the checksum, may be {@code null}.
* @return This task for chaining, never {@code null}.
*/
public GetTask setChecksum( String algorithm, String value )
{
if ( algorithm != null )
{
if ( checksums.isEmpty() )
{
checksums = new HashMap();
}
if ( value != null && value.length() > 0 )
{
checksums.put( algorithm, value );
}
else
{
checksums.remove( algorithm );
}
}
return this;
}
@Override
public String toString()
{
return "<< " + getLocation();
}
}