001 /* 002 * JBoss DNA (http://www.jboss.org/dna) 003 * See the COPYRIGHT.txt file distributed with this work for information 004 * regarding copyright ownership. Some portions may be licensed 005 * to Red Hat, Inc. under one or more contributor license agreements. 006 * See the AUTHORS.txt file in the distribution for a full listing of 007 * individual contributors. 008 * 009 * JBoss DNA is free software. Unless otherwise indicated, all code in JBoss DNA 010 * is licensed to you under the terms of the GNU Lesser General Public License as 011 * published by the Free Software Foundation; either version 2.1 of 012 * the License, or (at your option) any later version. 013 * 014 * JBoss DNA is distributed in the hope that it will be useful, 015 * but WITHOUT ANY WARRANTY; without even the implied warranty of 016 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 017 * Lesser General Public License for more details. 018 * 019 * You should have received a copy of the GNU Lesser General Public 020 * License along with this software; if not, write to the Free 021 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 022 * 02110-1301 USA, or see the FSF site: http://www.fsf.org. 023 */ 024 package org.jboss.dna.graph.property; 025 026 import java.io.File; 027 import java.io.IOException; 028 import java.io.InputStream; 029 import java.io.Reader; 030 031 /** 032 * A factory for creating {@link Binary} instances. This interface extends the {@link ValueFactory} generic interface and adds 033 * specific methods for creating binary objects. 034 * 035 * @author Randall Hauch 036 */ 037 public interface BinaryFactory extends ValueFactory<Binary> { 038 039 /** 040 * Create a value from the binary content given by the supplied stream, the approximate length, and the SHA-1 secure hash of 041 * the content. If the secure hash is null, then a secure hash is computed from the content. If the secure hash is not null, 042 * it is assumed to be the hash for the content and may not be checked. 043 * 044 * @param stream the stream containing the content to be used to create the value 045 * @param approximateLength the approximate length of the content (in bytes) 046 * @param secureHash the secure hash of the content in the <code>stream</code>; if null, the secure hash is computed from the 047 * content, and if not null it is assumed to be the correct secure hash (and is not checked) 048 * @return the value, or null if the supplied stream is null 049 * @throws ValueFormatException if the conversion from an input stream could not be performed 050 * @throws IoException If an unexpected problem occurs while accessing the supplied stream (such as an {@link IOException}). 051 * @throws IllegalArgumentException if the secure hash was discovered to be incorrect 052 */ 053 Binary create( InputStream stream, 054 long approximateLength, 055 byte[] secureHash ) throws ValueFormatException, IoException; 056 057 /** 058 * Create a value from the binary content given by the supplied reader, the approximate length, and the SHA-1 secure hash of 059 * the content. If the secure hash is null, then a secure hash is computed from the content. If the secure hash is not null, 060 * it is assumed to be the hash for the content and may not be checked. 061 * 062 * @param reader the reader containing the content to be used to create the value 063 * @param approximateLength the approximate length of the content (in bytes) 064 * @param secureHash the secure hash of the content in the <code>stream</code>; if null, the secure hash is computed from the 065 * content, and if not null it is assumed to be the correct secure hash (and is not checked) 066 * @return the value, or null if the supplied string is null 067 * @throws ValueFormatException if the conversion from a reader could not be performed 068 * @throws IoException If an unexpected problem occurs while accessing the supplied reader (such as an {@link IOException}). 069 * @throws IllegalArgumentException if the secure hash was discovered to be incorrect 070 */ 071 Binary create( Reader reader, 072 long approximateLength, 073 byte[] secureHash ) throws ValueFormatException, IoException; 074 075 /** 076 * Create a binary value from the given file. 077 * 078 * @param file the file containing the content to be used 079 * @return the binary value, or null if the file parameter was null 080 * @throws ValueFormatException if the conversion from the file could not be performed 081 * @throws IoException If an unexpected problem occurs while accessing the supplied file (such as an {@link IOException}). 082 */ 083 Binary create( File file ) throws ValueFormatException, IoException; 084 085 /** 086 * Find an existing binary value given the supplied secure hash. If no such binary value exists, null is returned. This method 087 * can be used when the caller knows the secure hash (e.g., from a previously-held Binary object), and would like to reuse an 088 * existing binary value (if possible) rather than recreate the binary value by processing the stream contents. This is 089 * especially true when the size of the binary is quite large. 090 * 091 * @param secureHash the secure hash of the binary content, which was probably {@link Binary#getHash() obtained} from a 092 * previously-held {@link Binary} object; a null or empty value is allowed, but will always result in returning null 093 * @return the existing Binary value that has the same secure hash, or null if there is no such value available at this time 094 */ 095 Binary find( byte[] secureHash ); 096 }