org.apache.avro.SchemaCompatibility Maven / Gradle / Ivy
/*
* 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
*
* 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.apache.avro;
import java.util.ArrayDeque;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.Deque;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Objects;
import java.util.Set;
import java.util.TreeSet;
import org.apache.avro.Schema.Field;
import org.apache.avro.Schema.Type;
import com.facebook.presto.hive.$internal.org.slf4j.Logger;
import com.facebook.presto.hive.$internal.org.slf4j.LoggerFactory;
/**
* Evaluate the compatibility between a reader schema and a writer schema. A
* reader and a writer schema are declared compatible if all datum instances of
* the writer schema can be successfully decoded using the specified reader
* schema.
*/
public class SchemaCompatibility {
private static final Logger LOG = LoggerFactory.getLogger(SchemaCompatibility.class);
/** Utility class cannot be instantiated. */
private SchemaCompatibility() {
}
/** Message to annotate reader/writer schema pairs that are compatible. */
public static final String READER_WRITER_COMPATIBLE_MESSAGE = "Reader schema can always successfully decode data written using the writer schema.";
/**
* Validates that the provided reader schema can be used to decode avro data
* written with the provided writer schema.
*
* @param reader schema to check.
* @param writer schema to check.
* @return a result object identifying any compatibility errors.
*/
public static SchemaPairCompatibility checkReaderWriterCompatibility(final Schema reader, final Schema writer) {
final SchemaCompatibilityResult compatibility = new ReaderWriterCompatibilityChecker().getCompatibility(reader,
writer);
final String message;
switch (compatibility.getCompatibility()) {
case INCOMPATIBLE: {
message = String.format(
"Data encoded using writer schema:%n%s%n" + "will or may fail to decode using reader schema:%n%s%n",
writer.toString(true), reader.toString(true));
break;
}
case COMPATIBLE: {
message = READER_WRITER_COMPATIBLE_MESSAGE;
break;
}
default:
throw new AvroRuntimeException("Unknown compatibility: " + compatibility);
}
return new SchemaPairCompatibility(compatibility, reader, writer, message);
}
// -----------------------------------------------------------------------------------------------
/**
* Tests the equality of two Avro named schemas.
*
*
* Matching includes reader name aliases.
*
*
* @param reader Named reader schema.
* @param writer Named writer schema.
* @return whether the names of the named schemas match or not.
*/
public static boolean schemaNameEquals(final Schema reader, final Schema writer) {
if (objectsEqual(reader.getName(), writer.getName())) {
return true;
}
// Apply reader aliases:
return reader.getAliases().contains(writer.getFullName());
}
/**
* Identifies the writer field that corresponds to the specified reader field.
*
*
* Matching includes reader name aliases.
*
*
* @param writerSchema Schema of the record where to look for the writer field.
* @param readerField Reader field to identify the corresponding writer field
* of.
* @return the writer field, if any does correspond, or None.
*/
public static Field lookupWriterField(final Schema writerSchema, final Field readerField) {
assert (writerSchema.getType() == Type.RECORD);
final List writerFields = new ArrayList<>();
final Field direct = writerSchema.getField(readerField.name());
if (direct != null) {
writerFields.add(direct);
}
for (final String readerFieldAliasName : readerField.aliases()) {
final Field writerField = writerSchema.getField(readerFieldAliasName);
if (writerField != null) {
writerFields.add(writerField);
}
}
switch (writerFields.size()) {
case 0:
return null;
case 1:
return writerFields.get(0);
default: {
throw new AvroRuntimeException(String.format(
"Reader record field %s matches multiple fields in writer record schema %s", readerField, writerSchema));
}
}
}
/**
* Reader/writer schema pair that can be used as a key in a hash map.
*
* This reader/writer pair differentiates Schema objects based on their system
* hash code.
*/
private static final class ReaderWriter {
private final Schema mReader;
private final Schema mWriter;
/**
* Initializes a new reader/writer pair.
*
* @param reader Reader schema.
* @param writer Writer schema.
*/
public ReaderWriter(final Schema reader, final Schema writer) {
mReader = reader;
mWriter = writer;
}
/** {@inheritDoc} */
@Override
public int hashCode() {
return System.identityHashCode(mReader) ^ System.identityHashCode(mWriter);
}
/** {@inheritDoc} */
@Override
public boolean equals(Object obj) {
if (!(obj instanceof ReaderWriter)) {
return false;
}
final ReaderWriter that = (ReaderWriter) obj;
// Use pointer comparison here:
return (this.mReader == that.mReader) && (this.mWriter == that.mWriter);
}
/** {@inheritDoc} */
@Override
public String toString() {
return String.format("ReaderWriter{reader:%s, writer:%s}", mReader, mWriter);
}
}
/**
* Determines the compatibility of a reader/writer schema pair.
*
*
* Provides memoization to handle recursive schemas.
*
*/
private static final class ReaderWriterCompatibilityChecker {
private static final String ROOT_REFERENCE_TOKEN = "";
private final Map mMemoizeMap = new HashMap<>();
/**
* Reports the compatibility of a reader/writer schema pair.
*
*
* Memoizes the compatibility results.
*
*
* @param reader Reader schema to test.
* @param writer Writer schema to test.
* @return the compatibility of the reader/writer schema pair.
*/
public SchemaCompatibilityResult getCompatibility(final Schema reader, final Schema writer) {
Deque location = new ArrayDeque<>();
return getCompatibility(ROOT_REFERENCE_TOKEN, reader, writer, location);
}
/**
* Reports the compatibility of a reader/writer schema pair.
*
* Memoizes the compatibility results.
*
*
* @param referenceToken The equivalent JSON pointer reference token
* representation of the schema node being visited.
* @param reader Reader schema to test.
* @param writer Writer schema to test.
* @param location Stack with which to track the location within the
* schema.
* @return the compatibility of the reader/writer schema pair.
*/
private SchemaCompatibilityResult getCompatibility(String referenceToken, final Schema reader, final Schema writer,
final Deque location) {
location.addFirst(referenceToken);
LOG.debug("Checking compatibility of reader {} with writer {}", reader, writer);
final ReaderWriter pair = new ReaderWriter(reader, writer);
SchemaCompatibilityResult result = mMemoizeMap.get(pair);
if (result != null) {
if (result.getCompatibility() == SchemaCompatibilityType.RECURSION_IN_PROGRESS) {
// Break the recursion here.
// schemas are compatible unless proven incompatible:
result = SchemaCompatibilityResult.compatible();
}
} else {
// Mark this reader/writer pair as "in progress":
mMemoizeMap.put(pair, SchemaCompatibilityResult.recursionInProgress());
result = calculateCompatibility(reader, writer, location);
mMemoizeMap.put(pair, result);
}
location.removeFirst();
return result;
}
/**
* Calculates the compatibility of a reader/writer schema pair.
*
*
* Relies on external memoization performed by
* {@link #getCompatibility(Schema, Schema)}.
*
*
* @param reader Reader schema to test.
* @param writer Writer schema to test.
* @param location Stack with which to track the location within the schema.
* @return the compatibility of the reader/writer schema pair.
*/
private SchemaCompatibilityResult calculateCompatibility(final Schema reader, final Schema writer,
final Deque location) {
assert (reader != null);
assert (writer != null);
SchemaCompatibilityResult result = SchemaCompatibilityResult.compatible();
if (reader.getType() == writer.getType()) {
switch (reader.getType()) {
case NULL:
case BOOLEAN:
case INT:
case LONG:
case FLOAT:
case DOUBLE:
case BYTES:
case STRING: {
return result;
}
case ARRAY: {
return result
.mergedWith(getCompatibility("items", reader.getElementType(), writer.getElementType(), location));
}
case MAP: {
return result.mergedWith(getCompatibility("values", reader.getValueType(), writer.getValueType(), location));
}
case FIXED: {
result = result.mergedWith(checkSchemaNames(reader, writer, location));
return result.mergedWith(checkFixedSize(reader, writer, location));
}
case ENUM: {
result = result.mergedWith(checkSchemaNames(reader, writer, location));
return result.mergedWith(checkReaderEnumContainsAllWriterEnumSymbols(reader, writer, location));
}
case RECORD: {
result = result.mergedWith(checkSchemaNames(reader, writer, location));
return result.mergedWith(checkReaderWriterRecordFields(reader, writer, location));
}
case UNION: {
// Check that each individual branch of the writer union can be decoded:
int i = 0;
for (final Schema writerBranch : writer.getTypes()) {
location.addFirst(Integer.toString(i));
SchemaCompatibilityResult compatibility = getCompatibility(reader, writerBranch);
if (compatibility.getCompatibility() == SchemaCompatibilityType.INCOMPATIBLE) {
String message = String.format("reader union lacking writer type: %s", writerBranch.getType());
result = result.mergedWith(SchemaCompatibilityResult.incompatible(
SchemaIncompatibilityType.MISSING_UNION_BRANCH, reader, writer, message, asList(location)));
}
location.removeFirst();
i++;
}
// Each schema in the writer union can be decoded with the reader:
return result;
}
default: {
throw new AvroRuntimeException("Unknown schema type: " + reader.getType());
}
}
} else {
// Reader and writer have different schema types:
// Reader compatible with all branches of a writer union is compatible
if (writer.getType() == Schema.Type.UNION) {
for (Schema s : writer.getTypes()) {
result = result.mergedWith(getCompatibility(reader, s));
}
return result;
}
switch (reader.getType()) {
case NULL:
return result.mergedWith(typeMismatch(reader, writer, location));
case BOOLEAN:
return result.mergedWith(typeMismatch(reader, writer, location));
case INT:
return result.mergedWith(typeMismatch(reader, writer, location));
case LONG: {
return (writer.getType() == Type.INT) ? result : result.mergedWith(typeMismatch(reader, writer, location));
}
case FLOAT: {
return ((writer.getType() == Type.INT) || (writer.getType() == Type.LONG)) ? result
: result.mergedWith(typeMismatch(reader, writer, location));
}
case DOUBLE: {
return ((writer.getType() == Type.INT) || (writer.getType() == Type.LONG) || (writer.getType() == Type.FLOAT))
? result
: result.mergedWith(typeMismatch(reader, writer, location));
}
case BYTES: {
return (writer.getType() == Type.STRING) ? result : result.mergedWith(typeMismatch(reader, writer, location));
}
case STRING: {
return (writer.getType() == Type.BYTES) ? result : result.mergedWith(typeMismatch(reader, writer, location));
}
case ARRAY:
return result.mergedWith(typeMismatch(reader, writer, location));
case MAP:
return result.mergedWith(typeMismatch(reader, writer, location));
case FIXED:
return result.mergedWith(typeMismatch(reader, writer, location));
case ENUM:
return result.mergedWith(typeMismatch(reader, writer, location));
case RECORD:
return result.mergedWith(typeMismatch(reader, writer, location));
case UNION: {
for (final Schema readerBranch : reader.getTypes()) {
SchemaCompatibilityResult compatibility = getCompatibility(readerBranch, writer);
if (compatibility.getCompatibility() == SchemaCompatibilityType.COMPATIBLE) {
return result;
}
}
// No branch in the reader union has been found compatible with the writer
// schema:
String message = String.format("reader union lacking writer type: %s", writer.getType());
return result.mergedWith(SchemaCompatibilityResult
.incompatible(SchemaIncompatibilityType.MISSING_UNION_BRANCH, reader, writer, message, asList(location)));
}
default: {
throw new AvroRuntimeException("Unknown schema type: " + reader.getType());
}
}
}
}
private SchemaCompatibilityResult checkReaderWriterRecordFields(final Schema reader, final Schema writer,
final Deque location) {
SchemaCompatibilityResult result = SchemaCompatibilityResult.compatible();
location.addFirst("fields");
// Check that each field in the reader record can be populated from the writer
// record:
for (final Field readerField : reader.getFields()) {
location.addFirst(Integer.toString(readerField.pos()));
final Field writerField = lookupWriterField(writer, readerField);
if (writerField == null) {
// Reader field does not correspond to any field in the writer record schema, so
// the
// reader field must have a default value.
if (!readerField.hasDefaultValue()) {
// reader field has no default value. Check for the enum default value
if (readerField.schema().getType() == Type.ENUM && readerField.schema().getEnumDefault() != null) {
result = result.mergedWith(getCompatibility("type", readerField.schema(), writer, location));
} else {
result = result.mergedWith(
SchemaCompatibilityResult.incompatible(SchemaIncompatibilityType.READER_FIELD_MISSING_DEFAULT_VALUE,
reader, writer, readerField.name(), asList(location)));
}
}
} else {
result = result.mergedWith(getCompatibility("type", readerField.schema(), writerField.schema(), location));
}
// POP field index
location.removeFirst();
}
// All fields in the reader record can be populated from the writer record:
// POP "fields" literal
location.removeFirst();
return result;
}
private SchemaCompatibilityResult checkReaderEnumContainsAllWriterEnumSymbols(final Schema reader,
final Schema writer, final Deque location) {
SchemaCompatibilityResult result = SchemaCompatibilityResult.compatible();
location.addFirst("symbols");
final Set symbols = new TreeSet<>(writer.getEnumSymbols());
symbols.removeAll(reader.getEnumSymbols());
if (!symbols.isEmpty()) {
if (reader.getEnumDefault() != null && reader.getEnumSymbols().contains(reader.getEnumDefault())) {
symbols.clear();
result = SchemaCompatibilityResult.compatible();
} else {
result = SchemaCompatibilityResult.incompatible(SchemaIncompatibilityType.MISSING_ENUM_SYMBOLS, reader,
writer, symbols.toString(), asList(location));
}
}
// POP "symbols" literal
location.removeFirst();
return result;
}
private SchemaCompatibilityResult checkFixedSize(final Schema reader, final Schema writer,
final Deque location) {
SchemaCompatibilityResult result = SchemaCompatibilityResult.compatible();
location.addFirst("size");
int actual = reader.getFixedSize();
int expected = writer.getFixedSize();
if (actual != expected) {
String message = String.format("expected: %d, found: %d", expected, actual);
result = SchemaCompatibilityResult.incompatible(SchemaIncompatibilityType.FIXED_SIZE_MISMATCH, reader, writer,
message, asList(location));
}
// POP "size" literal
location.removeFirst();
return result;
}
private SchemaCompatibilityResult checkSchemaNames(final Schema reader, final Schema writer,
final Deque location) {
SchemaCompatibilityResult result = SchemaCompatibilityResult.compatible();
location.addFirst("name");
if (!schemaNameEquals(reader, writer)) {
String message = String.format("expected: %s", writer.getFullName());
result = SchemaCompatibilityResult.incompatible(SchemaIncompatibilityType.NAME_MISMATCH, reader, writer,
message, asList(location));
}
// POP "name" literal
location.removeFirst();
return result;
}
private SchemaCompatibilityResult typeMismatch(final Schema reader, final Schema writer,
final Deque location) {
String message = String.format("reader type: %s not compatible with writer type: %s", reader.getType(),
writer.getType());
return SchemaCompatibilityResult.incompatible(SchemaIncompatibilityType.TYPE_MISMATCH, reader, writer, message,
asList(location));
}
}
/**
* Identifies the type of a schema compatibility result.
*/
public enum SchemaCompatibilityType {
COMPATIBLE, INCOMPATIBLE,
/** Used internally to tag a reader/writer schema pair and prevent recursion. */
RECURSION_IN_PROGRESS;
}
public enum SchemaIncompatibilityType {
NAME_MISMATCH, FIXED_SIZE_MISMATCH, MISSING_ENUM_SYMBOLS, READER_FIELD_MISSING_DEFAULT_VALUE, TYPE_MISMATCH,
MISSING_UNION_BRANCH;
}
/**
* Immutable class representing details about a particular schema pair
* compatibility check.
*/
public static final class SchemaCompatibilityResult {
/**
* Merges the current {@code SchemaCompatibilityResult} with the supplied result
* into a new instance, combining the list of
* {@code Incompatibility Incompatibilities} and regressing to the
* {@code SchemaCompatibilityType#INCOMPATIBLE INCOMPATIBLE} state if any
* incompatibilities are encountered.
*
* @param toMerge The {@code SchemaCompatibilityResult} to merge with the
* current instance.
* @return A {@code SchemaCompatibilityResult} that combines the state of the
* current and supplied instances.
*/
public SchemaCompatibilityResult mergedWith(SchemaCompatibilityResult toMerge) {
List mergedIncompatibilities = new ArrayList<>(mIncompatibilities);
mergedIncompatibilities.addAll(toMerge.getIncompatibilities());
SchemaCompatibilityType compatibilityType = mCompatibilityType == SchemaCompatibilityType.COMPATIBLE
? toMerge.mCompatibilityType
: SchemaCompatibilityType.INCOMPATIBLE;
return new SchemaCompatibilityResult(compatibilityType, mergedIncompatibilities);
}
private final SchemaCompatibilityType mCompatibilityType;
// the below fields are only valid if INCOMPATIBLE
private final List mIncompatibilities;
// cached objects for stateless details
private static final SchemaCompatibilityResult COMPATIBLE = new SchemaCompatibilityResult(
SchemaCompatibilityType.COMPATIBLE, Collections.emptyList());
private static final SchemaCompatibilityResult RECURSION_IN_PROGRESS = new SchemaCompatibilityResult(
SchemaCompatibilityType.RECURSION_IN_PROGRESS, Collections.emptyList());
private SchemaCompatibilityResult(SchemaCompatibilityType compatibilityType,
List incompatibilities) {
this.mCompatibilityType = compatibilityType;
this.mIncompatibilities = incompatibilities;
}
/**
* Returns a details object representing a compatible schema pair.
*
* @return a SchemaCompatibilityDetails object with COMPATIBLE
* SchemaCompatibilityType, and no other state.
*/
public static SchemaCompatibilityResult compatible() {
return COMPATIBLE;
}
/**
* Returns a details object representing a state indicating that recursion is in
* progress.
*
* @return a SchemaCompatibilityDetails object with RECURSION_IN_PROGRESS
* SchemaCompatibilityType, and no other state.
*/
public static SchemaCompatibilityResult recursionInProgress() {
return RECURSION_IN_PROGRESS;
}
/**
* Returns a details object representing an incompatible schema pair, including
* error details.
*
* @return a SchemaCompatibilityDetails object with INCOMPATIBLE
* SchemaCompatibilityType, and state representing the violating part.
*/
public static SchemaCompatibilityResult incompatible(SchemaIncompatibilityType incompatibilityType,
Schema readerFragment, Schema writerFragment, String message, List location) {
Incompatibility incompatibility = new Incompatibility(incompatibilityType, readerFragment, writerFragment,
message, location);
return new SchemaCompatibilityResult(SchemaCompatibilityType.INCOMPATIBLE,
Collections.singletonList(incompatibility));
}
/**
* Returns the SchemaCompatibilityType, always non-null.
*
* @return a SchemaCompatibilityType instance, always non-null
*/
public SchemaCompatibilityType getCompatibility() {
return mCompatibilityType;
}
/**
* If the compatibility is INCOMPATIBLE, returns {@link Incompatibility
* Incompatibilities} found, otherwise an empty list.
*
* @return a list of {@link Incompatibility Incompatibilities}, may be empty,
* never null.
*/
public List getIncompatibilities() {
return mIncompatibilities;
}
/** {@inheritDoc} */
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result + ((mCompatibilityType == null) ? 0 : mCompatibilityType.hashCode());
result = prime * result + ((mIncompatibilities == null) ? 0 : mIncompatibilities.hashCode());
return result;
}
/** {@inheritDoc} */
@Override
public boolean equals(Object obj) {
if (this == obj)
return true;
if (obj == null)
return false;
if (getClass() != obj.getClass())
return false;
SchemaCompatibilityResult other = (SchemaCompatibilityResult) obj;
if (mIncompatibilities == null) {
if (other.mIncompatibilities != null)
return false;
} else if (!mIncompatibilities.equals(other.mIncompatibilities))
return false;
return mCompatibilityType == other.mCompatibilityType;
}
/** {@inheritDoc} */
@Override
public String toString() {
return String.format("SchemaCompatibilityResult{compatibility:%s, incompatibilities:%s}", mCompatibilityType,
mIncompatibilities);
}
}
// -----------------------------------------------------------------------------------------------
public static final class Incompatibility {
private final SchemaIncompatibilityType mType;
private final Schema mReaderFragment;
private final Schema mWriterFragment;
private final String mMessage;
private final List mLocation;
Incompatibility(SchemaIncompatibilityType type, Schema readerFragment, Schema writerFragment, String message,
List location) {
super();
this.mType = type;
this.mReaderFragment = readerFragment;
this.mWriterFragment = writerFragment;
this.mMessage = message;
this.mLocation = location;
}
/**
* Returns the SchemaIncompatibilityType.
*
* @return a SchemaIncompatibilityType instance.
*/
public SchemaIncompatibilityType getType() {
return mType;
}
/**
* Returns the fragment of the reader schema that failed compatibility check.
*
* @return a Schema instance (fragment of the reader schema).
*/
public Schema getReaderFragment() {
return mReaderFragment;
}
/**
* Returns the fragment of the writer schema that failed compatibility check.
*
* @return a Schema instance (fragment of the writer schema).
*/
public Schema getWriterFragment() {
return mWriterFragment;
}
/**
* Returns a human-readable message with more details about what failed. Syntax
* depends on the SchemaIncompatibilityType.
*
* @see #getType()
* @return a String with details about the incompatibility.
*/
public String getMessage() {
return mMessage;
}
/**
* Returns a
* JSON
* Pointer describing the node location within the schema's JSON document
* tree where the incompatibility was encountered.
*
* @return JSON Pointer encoded as a string.
*/
public String getLocation() {
StringBuilder s = new StringBuilder("/");
boolean first = true;
// ignore root element
for (String coordinate : mLocation.subList(1, mLocation.size())) {
if (first) {
first = false;
} else {
s.append('/');
}
// Apply JSON pointer escaping.
s.append(coordinate.replace("~", "~0").replace("/", "~1"));
}
return s.toString();
}
/** {@inheritDoc} */
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result + ((mType == null) ? 0 : mType.hashCode());
result = prime * result + ((mReaderFragment == null) ? 0 : mReaderFragment.hashCode());
result = prime * result + ((mWriterFragment == null) ? 0 : mWriterFragment.hashCode());
result = prime * result + ((mMessage == null) ? 0 : mMessage.hashCode());
result = prime * result + ((mLocation == null) ? 0 : mLocation.hashCode());
return result;
}
/** {@inheritDoc} */
@Override
public boolean equals(Object obj) {
if (this == obj) {
return true;
}
if (obj == null) {
return false;
}
if (getClass() != obj.getClass()) {
return false;
}
Incompatibility other = (Incompatibility) obj;
if (mType != other.mType) {
return false;
}
if (mReaderFragment == null) {
if (other.mReaderFragment != null) {
return false;
}
} else if (!mReaderFragment.equals(other.mReaderFragment)) {
return false;
}
if (mWriterFragment == null) {
if (other.mWriterFragment != null) {
return false;
}
} else if (!mWriterFragment.equals(other.mWriterFragment)) {
return false;
}
if (mMessage == null) {
if (other.mMessage != null) {
return false;
}
} else if (!mMessage.equals(other.mMessage)) {
return false;
}
if (mLocation == null) {
return other.mLocation == null;
} else
return mLocation.equals(other.mLocation);
}
/** {@inheritDoc} */
@Override
public String toString() {
return String.format("Incompatibility{type:%s, location:%s, message:%s, reader:%s, writer:%s}", mType,
getLocation(), mMessage, mReaderFragment, mWriterFragment);
}
}
// -----------------------------------------------------------------------------------------------
/**
* Provides information about the compatibility of a single reader and writer
* schema pair.
*
* Note: This class represents a one-way relationship from the reader to the
* writer schema.
*/
public static final class SchemaPairCompatibility {
/** The details of this result. */
private final SchemaCompatibilityResult mResult;
/** Validated reader schema. */
private final Schema mReader;
/** Validated writer schema. */
private final Schema mWriter;
/** Human readable description of this result. */
private final String mDescription;
/**
* Constructs a new instance.
*
* @param result The result of the compatibility check.
* @param reader schema that was validated.
* @param writer schema that was validated.
* @param description of this compatibility result.
*/
public SchemaPairCompatibility(SchemaCompatibilityResult result, Schema reader, Schema writer, String description) {
mResult = result;
mReader = reader;
mWriter = writer;
mDescription = description;
}
/**
* Gets the type of this result.
*
* @return the type of this result.
*/
public SchemaCompatibilityType getType() {
return mResult.getCompatibility();
}
/**
* Gets more details about the compatibility, in particular if getType() is
* INCOMPATIBLE.
*
* @return the details of this compatibility check.
*/
public SchemaCompatibilityResult getResult() {
return mResult;
}
/**
* Gets the reader schema that was validated.
*
* @return reader schema that was validated.
*/
public Schema getReader() {
return mReader;
}
/**
* Gets the writer schema that was validated.
*
* @return writer schema that was validated.
*/
public Schema getWriter() {
return mWriter;
}
/**
* Gets a human readable description of this validation result.
*
* @return a human readable description of this validation result.
*/
public String getDescription() {
return mDescription;
}
/** {@inheritDoc} */
@Override
public String toString() {
return String.format("SchemaPairCompatibility{result:%s, readerSchema:%s, writerSchema:%s, description:%s}",
mResult, mReader, mWriter, mDescription);
}
/** {@inheritDoc} */
@Override
public boolean equals(Object other) {
if ((other instanceof SchemaPairCompatibility)) {
final SchemaPairCompatibility result = (SchemaPairCompatibility) other;
return objectsEqual(result.mResult, mResult) && objectsEqual(result.mReader, mReader)
&& objectsEqual(result.mWriter, mWriter) && objectsEqual(result.mDescription, mDescription);
} else {
return false;
}
}
/** {@inheritDoc} */
@Override
public int hashCode() {
return Arrays.hashCode(new Object[] { mResult, mReader, mWriter, mDescription });
}
}
/** Borrowed from Guava's Objects.equal(a, b) */
private static boolean objectsEqual(Object obj1, Object obj2) {
return Objects.equals(obj1, obj2);
}
private static List asList(Deque deque) {
List list = new ArrayList<>(deque);
Collections.reverse(list);
return Collections.unmodifiableList(list);
}
}