+/*
+ * Copyright (c) 2014 Cisco Systems, Inc. and others. All rights reserved.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v1.0 which accompanies this distribution,
+ * and is available at http://www.eclipse.org/legal/eplv10.html
+ */
package org.opendaylight.yangtools.yang.model.util.repo;
+import java.io.ByteArrayInputStream;
+import java.io.InputStream;
+
+import org.opendaylight.yangtools.concepts.Delegator;
+
+import com.google.common.base.Charsets;
+import com.google.common.base.Function;
import com.google.common.base.Optional;
+import com.google.common.base.Preconditions;
-public class SchemaSourceProviders {
+/**
+ *
+ * Utility functions for {@link SchemaSourceProvider}
+ *
+ */
+public final class SchemaSourceProviders {
@SuppressWarnings("rawtypes")
- private static final SchemaSourceProvider NOOP_PROVIDER = new SchemaSourceProvider() {
+ private static final SchemaSourceProvider NOOP_PROVIDER = new AdvancedSchemaSourceProvider() {
+
+ @Override
+ public Optional getSchemaSource(final String moduleName, final Optional revision) {
+ return Optional.absent();
+ }
@Override
- public Optional getSchemaSource(String moduleName, Optional revision) {
+ public Optional getSchemaSource(final SourceIdentifier sourceIdentifier) {
return Optional.absent();
}
};
+ @SuppressWarnings("rawtypes")
+ private static final SchemaSourceTransformation IDENTITY_TRANFORMATION = new IdentityTransformation();
+
+ private static final StringToInputStreamTransformation STRING_TO_INPUTSTREAM_TRANSFORMATION = new StringToInputStreamTransformation();
+
+ private SchemaSourceProviders() {
+ throw new UnsupportedOperationException("Utility class.");
+ }
+
+ /**
+ * Returns a noop schema source provider.
+ *
+ * Noop schema provider returns {@link Optional#absent()} for each call to
+ * query schema source.
+ *
+ * @return A reusable no-operation provider.
+ */
@SuppressWarnings("unchecked")
public static <T> SchemaSourceProvider<T> noopProvider() {
- return (SchemaSourceProvider<T>) NOOP_PROVIDER;
+ return NOOP_PROVIDER;
+ }
+
+ /**
+ *
+ * Returns delegating schema source provider which returns InputStream from
+ * supplied String based schema source provider.
+ *
+ * @param delegate
+ * @return InputStream-based source provider.
+ */
+ public static SchemaSourceProvider<InputStream> inputStreamProviderfromStringProvider(
+ final AdvancedSchemaSourceProvider<String> delegate) {
+ return TransformingSourceProvider.create(delegate, STRING_TO_INPUTSTREAM_TRANSFORMATION);
+ }
+
+ /**
+ * Returns identity implementation of SchemaSourceTransformation
+ *
+ * Identity implementation of SchemaSourceTransformation is useful
+ * for usecases where Input and Output of SchemaSourceTransformation
+ * are identitcal, and you want to reuse input as an output.
+ *
+ * This implementation is really simple <code>return input;</code>.
+ *
+ * @return Identity transformation.
+ */
+ @SuppressWarnings("unchecked")
+ public static <I> SchemaSourceTransformation<I, I> identityTransformation() {
+ return IDENTITY_TRANFORMATION;
+ }
+
+ public static <I, O> SchemaSourceTransformation<I, O> schemaSourceTransformationFrom(
+ final Function<I, O> transformation) {
+ return new FunctionBasedSchemaSourceTransformation<I, O>(transformation);
+ }
+
+ /**
+ *
+ * Casts {@link SchemaSourceProvider} to
+ * {@link AdvancedSchemaSourceProvider} or wraps it with utility
+ * implementation if supplied delegate does not implement
+ * {@link AdvancedSchemaSourceProvider}.
+ *
+ * @param schemaSourceProvider
+ */
+ public static <O> AdvancedSchemaSourceProvider<O> toAdvancedSchemaSourceProvider(
+ final SchemaSourceProvider<O> schemaSourceProvider) {
+ if (schemaSourceProvider instanceof AdvancedSchemaSourceProvider<?>) {
+ return (AdvancedSchemaSourceProvider<O>) schemaSourceProvider;
+ }
+ return new SchemaSourceCompatibilityWrapper<O>(schemaSourceProvider);
+ }
+
+ private static final class FunctionBasedSchemaSourceTransformation<I, O> implements
+ SchemaSourceTransformation<I, O> {
+
+
+ private final Function<I, O> delegate;
+
+ protected FunctionBasedSchemaSourceTransformation(final Function<I, O> delegate) {
+ super();
+ this.delegate = Preconditions.checkNotNull(delegate, "delegate MUST NOT be null.");
+ }
+
+ @Override
+ public O transform(final I input) {
+ return delegate.apply(input);
+ }
+
+ @Override
+ public String toString() {
+ return "FunctionBasedSchemaSourceTransformation [delegate=" + delegate + "]";
+ }
+ }
+
+ private final static class SchemaSourceCompatibilityWrapper<O> implements //
+ AdvancedSchemaSourceProvider<O>, //
+ Delegator<SchemaSourceProvider<O>> {
+
+ private final SchemaSourceProvider<O> delegate;
+
+ public SchemaSourceCompatibilityWrapper(final SchemaSourceProvider<O> delegate) {
+ this.delegate = delegate;
+ }
+
+ @Override
+ public SchemaSourceProvider<O> getDelegate() {
+ return delegate;
+ }
+
+
+ /*
+ * Deprecation warnings are suppresed, since this implementation
+ * needs to invoke deprecated method in order to provide
+ * implementation of non-deprecated APIs using legacy ones.
+ *
+ * (non-Javadoc)
+ * @see org.opendaylight.yangtools.yang.model.util.repo.AdvancedSchemaSourceProvider#getSchemaSource(org.opendaylight.yangtools.yang.model.util.repo.SourceIdentifier)
+ */
+ @SuppressWarnings("deprecation")
+ @Override
+ public Optional<O> getSchemaSource(final SourceIdentifier sourceIdentifier) {
+
+ final String moduleName = sourceIdentifier.getName();
+ Optional<String> revision = Optional.fromNullable(sourceIdentifier.getRevision());
+ return delegate.getSchemaSource(moduleName, revision);
+ }
+
+ /*
+ * Deprecation warnings are suppresed, since this implementation
+ * needs to invoke deprecated method in order to provide
+ * implementation of non-deprecated APIs using legacy ones.
+ *
+ * (non-Javadoc)
+ * @see org.opendaylight.yangtools.yang.model.util.repo.AdvancedSchemaSourceProvider#getSchemaSource(org.opendaylight.yangtools.yang.model.util.repo.SourceIdentifier)
+ */
+ @Override
+ @SuppressWarnings("deprecation")
+ public Optional<O> getSchemaSource(final String moduleName, final Optional<String> revision) {
+ return delegate.getSchemaSource(moduleName, revision);
+ }
+ }
+
+ @SuppressWarnings("rawtypes")
+ private static class IdentityTransformation implements SchemaSourceTransformation {
+
+ @Override
+ public Object transform(final Object input) {
+ return input;
+ }
+ }
+
+ private static class StringToInputStreamTransformation implements SchemaSourceTransformation<String, InputStream> {
+
+ @Override
+ public InputStream transform(final String input) {
+ return new ByteArrayInputStream(input.getBytes(Charsets.UTF_8));
+ }
+
}
}
Code Review / yangtools.git / blobdiff