Author: jsorel
Date: Mon Feb 19 10:45:28 2018
New Revision: 1824731
URL: http://svn.apache.org/viewvc?rev=1824731&view=rev
Log:
DataStore : add FileSystemProvider interface to declare format suffix,signature
and factorize probContent implementations
Added:
sis/branches/JDK8/storage/sis-storage/src/main/java/org/apache/sis/internal/storage/FileSystemProvider.java
Modified:
sis/branches/JDK8/storage/sis-storage/src/main/java/org/apache/sis/internal/storage/URIDataStore.java
Added:
sis/branches/JDK8/storage/sis-storage/src/main/java/org/apache/sis/internal/storage/FileSystemProvider.java
URL:
http://svn.apache.org/viewvc/sis/branches/JDK8/storage/sis-storage/src/main/java/org/apache/sis/internal/storage/FileSystemProvider.java?rev=1824731&view=auto
==============================================================================
---
sis/branches/JDK8/storage/sis-storage/src/main/java/org/apache/sis/internal/storage/FileSystemProvider.java
(added)
+++
sis/branches/JDK8/storage/sis-storage/src/main/java/org/apache/sis/internal/storage/FileSystemProvider.java
Mon Feb 19 10:45:28 2018
@@ -0,0 +1,106 @@
+/*
+ * 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.
+ */
+package org.apache.sis.internal.storage;
+
+import java.nio.ByteBuffer;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.Collections;
+import org.apache.sis.storage.DataStoreException;
+import org.apache.sis.storage.DataStoreProvider;
+import org.apache.sis.storage.ProbeResult;
+import org.apache.sis.storage.StorageConnector;
+
+/**
+ * Files-related {@linkplain org.apache.sis.storage.DataStoreProvider
provider}.
+ * This interface provides additional descriptive informations on the supported
+ * file types.
+ *
+ * @author Johann Sorel (Geomatys)
+ * @since 1.0
+ * @module
+ */
+public interface FileSystemProvider {
+
+ /**
+ * Get the list of this format mainly used file suffixes.
+ * If the provider uses multiple files, this method should return
+ * only the entry file suffixes.
+ * <p>
+ * For example : the shapefile format uses the files shp,shx,dbf,qix,...
+ * but this collection only return the shp suffix.
+ * </p>
+ *
+ * @return list of suffix, case insensitive, never null, can be empty.
+ */
+ Collection<String> getSuffix();
+
+ /**
+ * Binary and sometimes text formats often have a special header at the
beginning
+ * of the file.
+ * This part of the file is call Signature or Magic number and is used by
+ * file explorers and applications to identify the file type.
+ *
+ * <p>Some format may declare multiple different signatures. Such case can
+ * happen for various reasons like historical evolution and changes on
version updates.</p>
+ *
+ * <p>Default implementation returns an empty collection.</p>
+ *
+ * @return collection of signatures, never null, can be empty.
+ */
+ default Collection<byte[]> getSignature() {
+ return Collections.EMPTY_LIST;
+ }
+
+ /**
+ * Specialized implementation of {@linkplain
DataStoreProvider#probeContent(org.apache.sis.storage.StorageConnector)
probeContent}.
+ * This implementation checks the input signature.
+ *
+ * @param connector information about the storage (URL, stream, JDBC
connection, <i>etc</i>).
+ * @return {@link ProbeResult#SUPPORTED} if the given storage seems to be
readable by the {@code DataStore}
+ * instances created by this provider.
+ * @throws DataStoreException if an I/O or SQL error occurred. The error
shall be unrelated to the logical
+ * structure of the storage.
+ */
+ default ProbeResult probeContent(StorageConnector connector) throws
DataStoreException {
+
+ final Collection<byte[]> signatures = getSignature();
+ if (signatures.isEmpty()) return ProbeResult.UNSUPPORTED_STORAGE;
+
+ final ByteBuffer buffer = connector.getStorageAs(ByteBuffer.class);
+ if (buffer != null) {
+ for (byte[] signature : signatures) {
+ try {
+ if (buffer.remaining() < signature.length) {
+ continue;
+ }
+ final byte[] candidate = new byte[signature.length];
+ buffer.get(candidate);
+
+ //compare signatures
+ if (Arrays.equals(signature, candidate)) {
+ return ProbeResult.SUPPORTED;
+ }
+ } finally {
+ buffer.reset();
+ }
+ }
+ }
+ return ProbeResult.UNSUPPORTED_STORAGE;
+ }
+
+}
Modified:
sis/branches/JDK8/storage/sis-storage/src/main/java/org/apache/sis/internal/storage/URIDataStore.java
URL:
http://svn.apache.org/viewvc/sis/branches/JDK8/storage/sis-storage/src/main/java/org/apache/sis/internal/storage/URIDataStore.java?rev=1824731&r1=1824730&r2=1824731&view=diff
==============================================================================
---
sis/branches/JDK8/storage/sis-storage/src/main/java/org/apache/sis/internal/storage/URIDataStore.java
[UTF-8] (original)
+++
sis/branches/JDK8/storage/sis-storage/src/main/java/org/apache/sis/internal/storage/URIDataStore.java
[UTF-8] Mon Feb 19 10:45:28 2018
@@ -102,7 +102,7 @@ public abstract class URIDataStore exten
* @since 0.8
* @module
*/
- public abstract static class Provider extends DataStoreProvider {
+ public abstract static class Provider extends DataStoreProvider implements
FileSystemProvider {
/**
* Description of the location parameter.
*/
