/*
* Copyright 2002-2007 the original author or authors.
*
* Licensed 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.
*/
package org.springframework.core.io;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.Arrays;
/**
* {@link Resource} implementation for a given byte array.
* Creates a ByteArrayInputStreams for the given byte array.
*
* <p>Useful for loading content from any given byte array,
* without having to resort to a single-use {@link InputStreamResource}.
* Particularly useful for creating mail attachments from local content,
* where JavaMail needs to be able to read the stream multiple times.
*
* @author Juergen Hoeller
* @since 1.2.3
* @see java.io.ByteArrayInputStream
* @see InputStreamResource
* @see org.springframework.mail.javamail.MimeMessageHelper#addAttachment(String, InputStreamSource)
*/
public class ByteArrayResource extends AbstractResource {
private final byte[] byteArray;
private final String description;
/**
* Create a new ByteArrayResource.
* @param byteArray the byte array to wrap
*/
public ByteArrayResource(byte[] byteArray) {
this(byteArray, "resource loaded from byte array");
}
/**
* Create a new ByteArrayResource.
* @param byteArray the byte array to wrap
* @param description where the byte array comes from
*/
public ByteArrayResource(byte[] byteArray, String description) {
if (byteArray == null) {
throw new IllegalArgumentException("Byte array must not be null");
}
this.byteArray = byteArray;
this.description = (description != null ? description : "");
}
/**
* Return the underlying byte array.
*/
public final byte[] getByteArray() {
return this.byteArray;
}
/**
* This implementation always returns <code>true</code>.
*/
@Override
public boolean exists() {
return true;
}
/**
* This implementation returns a ByteArrayInputStream for the
* underlying byte array.
* @see java.io.ByteArrayInputStream
*/
public InputStream getInputStream() throws IOException {
return new ByteArrayInputStream(this.byteArray);
}
/**
* This implementation returns the passed-in description, if any.
*/
public String getDescription() {
return this.description;
}
/**
* This implementation compares the underlying byte array.
* @see java.util.Arrays#equals(byte[], byte[])
*/
@Override
public boolean equals(Object obj) {
return (obj == this ||
(obj instanceof ByteArrayResource && Arrays.equals(((ByteArrayResource) obj).byteArray, this.byteArray)));
}
/**
* This implementation returns the hash code based on the
* underlying byte array.
*/
@Override
public int hashCode() {
return (byte[].class.hashCode() * 29 * this.byteArray.length);
}
}
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