Add AbstractResourceReader base class defining operations common to all ResourceReaders.
Resolves gh-92.
This commit is contained in:
John Blum
@@ -0,0 +1,92 @@
|
||||
/*
|
||||
* Copyright 2020 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
|
||||
*
|
||||
* https://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.geode.core.io;
|
||||
|
||||
import java.io.IOException;
|
||||
import java.io.InputStream;
|
||||
import java.util.Optional;
|
||||
|
||||
import org.springframework.core.io.Resource;
|
||||
import org.springframework.dao.DataAccessResourceFailureException;
|
||||
import org.springframework.geode.core.io.support.ResourceUtils;
|
||||
import org.springframework.lang.NonNull;
|
||||
import org.springframework.lang.Nullable;
|
||||
|
||||
/**
|
||||
* Abstract base class providing functionality common to all {@link ResourceReader} implementations.
|
||||
*
|
||||
* @author John Blum
|
||||
* @see java.io.InputStream
|
||||
* @see org.springframework.core.io.Resource
|
||||
* @see ResourceReader
|
||||
* @since 1.3.1
|
||||
*/
|
||||
public abstract class AbstractResourceReader implements ResourceReader {
|
||||
|
||||
/**
|
||||
* @inheritDoc
|
||||
*/
|
||||
@Override
|
||||
public @NonNull byte[] read(@NonNull Resource resource) {
|
||||
|
||||
return Optional.ofNullable(resource)
|
||||
.filter(this::isAbleToHandle)
|
||||
.map(it -> {
|
||||
try (InputStream in = it.getInputStream()) {
|
||||
return doRead(in);
|
||||
}
|
||||
catch (IOException cause) {
|
||||
throw new DataAccessResourceFailureException(String.format("Failed to read from Resource [%s]",
|
||||
it.getDescription()), cause);
|
||||
}
|
||||
})
|
||||
.orElseThrow(() -> new UnhandledResourceException(String.format("Unable to handle Resource [%s]",
|
||||
ResourceUtils.nullSafeGetDescription(resource))));
|
||||
}
|
||||
|
||||
/**
|
||||
* Determines whether this reader is able to handle and read from the target {@link Resource}.
|
||||
*
|
||||
* The default implementation determines that the {@link Resource} can be handled if the {@link Resource} handle
|
||||
* is not {@literal null}.
|
||||
*
|
||||
* @param resource {@link Resource} to evaluate.
|
||||
* @return a boolean value indicating whether this reader is able to handle and read from
|
||||
* the target {@link Resource}.
|
||||
* @see org.springframework.core.io.Resource
|
||||
*/
|
||||
@SuppressWarnings("unused")
|
||||
protected boolean isAbleToHandle(@Nullable Resource resource) {
|
||||
return resource != null;
|
||||
}
|
||||
|
||||
/**
|
||||
* Reads data from the target {@link Resource} (intentionally) by using the {@link InputStream} returned by
|
||||
* {@link Resource#getInputStream()}.
|
||||
*
|
||||
* However, other algorithm/strategy implementations are free to read from the {@link Resource} as is appropriate
|
||||
* for the given context (e.g. cloud environment). In those cases, implementors should override
|
||||
* the {@link #read(Resource)} method.
|
||||
*
|
||||
* @param resourceInputStream {@link InputStream} used to read data from the target {@link Resource}.
|
||||
* @return a {@literal non-null} byte array containing the data from the target {@link Resource}.
|
||||
* @throws IOException if an I/O error occurs while reading from the {@link Resource}.
|
||||
* @see java.io.InputStream
|
||||
* @see #read(Resource)
|
||||
*/
|
||||
protected abstract @NonNull byte[] doRead(@NonNull InputStream resourceInputStream) throws IOException;
|
||||
|
||||
}
|
||||
@@ -0,0 +1,153 @@
|
||||
/*
|
||||
* Copyright 2020 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
|
||||
*
|
||||
* https://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.geode.core.io;
|
||||
|
||||
import static org.assertj.core.api.Assertions.assertThat;
|
||||
import static org.mockito.ArgumentMatchers.any;
|
||||
import static org.mockito.ArgumentMatchers.eq;
|
||||
import static org.mockito.Mockito.doCallRealMethod;
|
||||
import static org.mockito.Mockito.doReturn;
|
||||
import static org.mockito.Mockito.doThrow;
|
||||
import static org.mockito.Mockito.mock;
|
||||
import static org.mockito.Mockito.times;
|
||||
import static org.mockito.Mockito.verify;
|
||||
import static org.mockito.Mockito.verifyNoInteractions;
|
||||
import static org.mockito.Mockito.verifyNoMoreInteractions;
|
||||
|
||||
import java.io.IOException;
|
||||
import java.io.InputStream;
|
||||
|
||||
import org.junit.Test;
|
||||
|
||||
import org.springframework.core.io.Resource;
|
||||
import org.springframework.dao.DataAccessResourceFailureException;
|
||||
|
||||
/**
|
||||
* Unit Tests for {@link AbstractResourceReader}.
|
||||
*
|
||||
* @author John Blum
|
||||
* @see org.junit.Test
|
||||
* @see org.mockito.Mockito
|
||||
* @see org.springframework.core.io.Resource
|
||||
* @see org.springframework.geode.core.io.AbstractResourceReader
|
||||
* @since 1.3.1
|
||||
*/
|
||||
public class AbstractResourceReaderUnitTests {
|
||||
|
||||
@Test
|
||||
public void readCallsDoRead() throws IOException {
|
||||
|
||||
byte[] array = { (byte) 0xCA, (byte) 0xFE, (byte) 0xBA, (byte) 0xBE };
|
||||
|
||||
AbstractResourceReader mockResourceReader = mock(AbstractResourceReader.class);
|
||||
|
||||
InputStream mockInputStream = mock((InputStream.class));
|
||||
|
||||
Resource mockResource = mock(Resource.class);
|
||||
|
||||
doCallRealMethod().when(mockResourceReader).read(any());
|
||||
doReturn(true).when(mockResourceReader).isAbleToHandle(eq(mockResource));
|
||||
doReturn(array).when(mockResourceReader).doRead(eq(mockInputStream));
|
||||
doReturn(mockInputStream).when(mockResource).getInputStream();
|
||||
|
||||
assertThat(mockResourceReader.read(mockResource)).isEqualTo(array);
|
||||
|
||||
verify(mockResourceReader, times(1)).isAbleToHandle(eq(mockResource));
|
||||
verify(mockResourceReader, times(1)).doRead(eq(mockInputStream));
|
||||
verify(mockInputStream, times(1)).close();
|
||||
verify(mockResource, times(1)).getInputStream();
|
||||
verifyNoMoreInteractions(mockInputStream, mockResource);
|
||||
}
|
||||
|
||||
@Test(expected = UnhandledResourceException.class)
|
||||
public void readFromNullResourceThrowsUnhandledResourceException() {
|
||||
|
||||
AbstractResourceReader mockResourceReader = mock(AbstractResourceReader.class);
|
||||
|
||||
doCallRealMethod().when(mockResourceReader).read(any());
|
||||
|
||||
try {
|
||||
mockResourceReader.read(null);
|
||||
}
|
||||
catch (UnhandledResourceException expected) {
|
||||
|
||||
assertThat(expected).hasMessage("Unable to handle Resource [null]");
|
||||
assertThat(expected).hasNoCause();
|
||||
|
||||
throw expected;
|
||||
}
|
||||
}
|
||||
|
||||
@Test(expected = DataAccessResourceFailureException.class)
|
||||
public void readThrowsDataAccessResourceFailureExceptionOnIoException() throws IOException {
|
||||
|
||||
AbstractResourceReader mockResourceReader = mock(AbstractResourceReader.class);
|
||||
|
||||
InputStream mockInputStream = mock((InputStream.class));
|
||||
|
||||
Resource mockResource = mock(Resource.class);
|
||||
|
||||
doCallRealMethod().when(mockResourceReader).read(any());
|
||||
doReturn(true).when(mockResourceReader).isAbleToHandle(eq(mockResource));
|
||||
doThrow(new IOException("TEST")).when(mockResourceReader).doRead(eq(mockInputStream));
|
||||
doReturn("MOCK").when(mockResource).getDescription();
|
||||
doReturn(mockInputStream).when(mockResource).getInputStream();
|
||||
|
||||
try {
|
||||
mockResourceReader.read(mockResource);
|
||||
}
|
||||
catch (DataAccessResourceFailureException expected) {
|
||||
|
||||
assertThat(expected).hasMessageStartingWith("Failed to read from Resource [MOCK]");
|
||||
assertThat(expected).hasCauseInstanceOf(IOException.class);
|
||||
assertThat(expected.getCause()).hasMessage("TEST");
|
||||
assertThat(expected.getCause()).hasNoCause();
|
||||
|
||||
throw expected;
|
||||
}
|
||||
finally {
|
||||
verify(mockResourceReader, times(1)).doRead(eq(mockInputStream));
|
||||
verify(mockInputStream, times(1)).close();
|
||||
verify(mockResource, times(1)).getDescription();
|
||||
verify(mockResource, times(1)).getInputStream();
|
||||
verifyNoMoreInteractions(mockInputStream, mockResource);
|
||||
}
|
||||
}
|
||||
|
||||
@Test
|
||||
public void isAbleToHandleNonNullResourceReturnsTrue() {
|
||||
|
||||
Resource mockResource = mock(Resource.class);
|
||||
|
||||
AbstractResourceReader mockResourceReader = mock(AbstractResourceReader.class);
|
||||
|
||||
doCallRealMethod().when(mockResourceReader).isAbleToHandle(any());
|
||||
|
||||
assertThat(mockResourceReader.isAbleToHandle(mockResource)).isTrue();
|
||||
|
||||
verifyNoInteractions(mockResource);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void isAbleToHandleNullResourceReturnsFalse() {
|
||||
|
||||
AbstractResourceReader mockResourceReader = mock(AbstractResourceReader.class);
|
||||
|
||||
doCallRealMethod().when(mockResourceReader).isAbleToHandle(any());
|
||||
|
||||
assertThat(mockResourceReader.isAbleToHandle(null)).isFalse();
|
||||
}
|
||||
}
|
||||
Reference in New Issue
Block a user