com.google.api.generator.gapic.composer.ClientLibraryReflectConfigComposer Maven / Gradle / Ivy
// Copyright 2023 Google LLC
//
// 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
//
// 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 com.google.api.generator.gapic.composer;
import com.google.api.client.util.Preconditions;
import com.google.api.generator.gapic.model.GapicContext;
import com.google.api.generator.gapic.model.Message;
import com.google.api.generator.gapic.model.ReflectConfig;
import com.google.common.annotations.VisibleForTesting;
import com.google.common.collect.ImmutableList;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
public class ClientLibraryReflectConfigComposer {
private ClientLibraryReflectConfigComposer() {} // Disallow instance creation
public static List generateReflectConfig(GapicContext context) {
List allConfigs = new ArrayList<>();
context
.messages()
.forEach(
(fullyQualifiedClassName, msg) ->
allConfigs.addAll(calculateReflectConfigList(fullyQualifiedClassName, msg)));
List duplicates = calculateDuplicates(allConfigs);
Preconditions.checkState(
duplicates.isEmpty(), "Duplicate binary name entries found: %s", duplicates);
return allConfigs.stream()
.sorted()
.map(ReflectConfig::new)
.collect(ImmutableList.toImmutableList());
}
/**
* List the binary names of all classes in the Message that should have a reflect-config entry.
*
* Note: Each reflect-config 'name' entry must be the "binary name" of a class to prevent
* ClassNotFoundException warnings during the native-image build.
*
*
Binary names (ex: `foo.Bar$Baz`) are guaranteed to be unique within a jar. By contrast,
* fully qualified class names (ex: `foo.Bar.Baz`) are only unique if standard Java package naming
* conventions are followed. A class `Baz` in package `foo.Bar` would have the same fully
* qualified class name as a nested class `Baz` in the class `Bar` in package `foo`.
*
*
See also the Java Language Specification @ 13.1.1 and 13.1.2 for specifics on the binary
* name format.
*/
@VisibleForTesting
static List calculateReflectConfigList(String fullyQualifiedClassName, Message message) {
final String binaryName = convertToBinaryName(fullyQualifiedClassName);
List list = new ArrayList<>();
list.add(binaryName);
for (String nestedEnum : message.nestedEnums()) {
list.add(binaryName + "$" + nestedEnum);
}
if (!message.isEnum()) {
list.add(binaryName + "$Builder");
}
return list;
}
/**
* Replace '.' with '$' in fully qualified class names once the classes become nested.
*
* For example, the fully qualified class name `com.google.foo.Bar.Baz.Car` becomes the binary
* name `com.google.foo.Bar$Baz$Car`.
*
*
This conversion works only when following standard Java naming conventions that packages
* always start with a lowercase letter, and classes always start with an uppercase letter.
*/
@VisibleForTesting
static String convertToBinaryName(String fullyQualifiedClassName) {
StringBuilder result = new StringBuilder();
boolean isNested = false;
for (String s : fullyQualifiedClassName.split("\\.")) {
if (result.length() != 0) {
result.append(isNested ? "$" : ".");
}
result.append(s);
if (Character.isUpperCase(s.charAt(0))) {
isNested = true;
}
}
return result.toString();
}
@VisibleForTesting
static List calculateDuplicates(List allConfigs) {
List duplicates = new ArrayList<>(allConfigs);
new HashSet<>(allConfigs).forEach(duplicates::remove);
return duplicates;
}
}