org.bouncycastle.cms.CMSCompressedData.java Source code

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Here is the source code for org.bouncycastle.cms.CMSCompressedData.java

Source

package org.bouncycastle.cms;

import java.io.IOException;
import java.io.InputStream;

import org.bouncycastle.asn1.ASN1ObjectIdentifier;
import org.bouncycastle.asn1.ASN1OctetString;
import org.bouncycastle.asn1.cms.CompressedData;
import org.bouncycastle.asn1.cms.ContentInfo;
import org.bouncycastle.operator.InputExpander;
import org.bouncycastle.operator.InputExpanderProvider;
import org.bouncycastle.util.Encodable;

/**
 * containing class for an CMS Compressed Data object
 * <pre>
 *     CMSCompressedData cd = new CMSCompressedData(inputStream);
 *
 *     process(cd.getContent(new ZlibExpanderProvider()));
 * </pre>
 */
public class CMSCompressedData implements Encodable {
    ContentInfo contentInfo;
    CompressedData comData;

    public CMSCompressedData(byte[] compressedData) throws CMSException {
        this(CMSUtils.readContentInfo(compressedData));
    }

    public CMSCompressedData(InputStream compressedData) throws CMSException {
        this(CMSUtils.readContentInfo(compressedData));
    }

    public CMSCompressedData(ContentInfo contentInfo) throws CMSException {
        this.contentInfo = contentInfo;

        try {
            this.comData = CompressedData.getInstance(contentInfo.getContent());
        } catch (ClassCastException e) {
            throw new CMSException("Malformed content.", e);
        } catch (IllegalArgumentException e) {
            throw new CMSException("Malformed content.", e);
        }
    }

    public ASN1ObjectIdentifier getContentType() {
        return contentInfo.getContentType();
    }

    /**
     * Return the uncompressed content.
     *
     * @param expanderProvider a provider of expander algorithm implementations.
     * @return the uncompressed content
     * @throws CMSException if there is an exception un-compressing the data.
     */
    public byte[] getContent(InputExpanderProvider expanderProvider) throws CMSException {
        ContentInfo content = comData.getEncapContentInfo();

        ASN1OctetString bytes = (ASN1OctetString) content.getContent();
        InputExpander expander = expanderProvider.get(comData.getCompressionAlgorithmIdentifier());
        InputStream zIn = expander.getInputStream(bytes.getOctetStream());

        try {
            return CMSUtils.streamToByteArray(zIn);
        } catch (IOException e) {
            throw new CMSException("exception reading compressed stream.", e);
        }
    }

    /**
     * return the ContentInfo
     */
    public ContentInfo toASN1Structure() {
        return contentInfo;
    }

    /**
     * return the ASN.1 encoded representation of this object.
     */
    public byte[] getEncoded() throws IOException {
        return contentInfo.getEncoded();
    }
}