Use linked versions of map and set

.chronus/changes/UseLinkedVersionsOfMapAndSet-2026-1-19-23-31-45.md

@@ -0,0 +1,8 @@
+---
+# Change versionKind to one of: internal, fix, dependencies, feature, deprecation, breaking
+changeKind: fix
+packages:
+  - "@typespec/http-client-java"
+---
+
+Use `LinkedHashMap` and `LinkedHashSet` to ensure consistent iterating order.

packages/http-client-java/CHANGELOG.md

@@ -1,7 +1,5 @@
 # Changelog - @typespec/http-client-java
 
-
-
 ## 0.7.0
 
 ### Features
@@ -22,4 +20,5 @@
 - [#9677](https://github.com/microsoft/typespec/pull/9677) Fix incorrect variable name of continuationToken
 - [#9527](https://github.com/microsoft/typespec/pull/9527) Missing example value for BinaryData type in mock test.
 - [#9639](https://github.com/microsoft/typespec/pull/9639) Fix mock data for BinaryData.
-
+- [#9751](https://github.com/microsoft/typespec/pull/9751) Use `LinkedHashMap` and `LinkedHashSet` to ensure consistent
+  iterating order.

packages/http-client-java/generator/http-client-generator-core/src/main/java/com/microsoft/typespec/http/client/generator/core/Javagen.java

@@ -38,7 +38,6 @@
 import com.microsoft.typespec.http.client.generator.core.util.ClientModelUtil;
 import com.microsoft.typespec.http.client.generator.core.util.SchemaUtil;
 import io.clientcore.core.utils.CoreUtils;
-import java.util.Collections;
 import java.util.List;
 import java.util.Set;
 import java.util.stream.Collectors;
@@ -166,7 +165,7 @@ protected JavaPackage writeToTemplates(CodeModel codeModel, Client client, JavaS
                     && client.getSyncClients().stream().anyMatch(c -> c.getClientBuilder() != null)) {
                     List<ServiceClient> serviceClients = client.getServiceClients();
                     if (CoreUtils.isNullOrEmpty(serviceClients)) {
-                        serviceClients = Collections.singletonList(client.getServiceClient());
+                        serviceClients = List.of(client.getServiceClient());
                     }
                     TestContext<Void> testContext = new TestContext<>(serviceClients, client.getSyncClients());
 

packages/http-client-java/generator/http-client-generator-core/src/main/java/com/microsoft/typespec/http/client/generator/core/extension/model/codemodel/Client.java

@@ -4,7 +4,6 @@
 package com.microsoft.typespec.http.client.generator.core.extension.model.codemodel;
 
 import java.util.ArrayList;
-import java.util.Collections;
 import java.util.List;
 
 /**
@@ -18,7 +17,7 @@ public class Client extends Metadata {
     private List<ApiVersion> apiVersions = new ArrayList<>();
     private ServiceVersion serviceVersion;
     private Client parent;
-    private List<Client> subClients = Collections.emptyList();
+    private List<Client> subClients = List.of();
     private boolean buildMethodPublic = true;
     private boolean parentAccessorPublic = false;
 

packages/http-client-java/generator/http-client-generator-core/src/main/java/com/microsoft/typespec/http/client/generator/core/extension/model/codemodel/CodeModelCustomConstructor.java

@@ -5,7 +5,7 @@
 
 import com.microsoft.typespec.http.client.generator.core.extension.model.extensionmodel.XmsExamples;
 import java.util.ArrayList;
-import java.util.HashMap;
+import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
 import org.yaml.snakeyaml.LoaderOptions;
@@ -381,7 +381,7 @@ public Object construct(Node node) {
         protected Object constructJavaBean2ndStep(MappingNode node, Object object) {
             if (node.getType().equals(XmsExamples.class)) {
                 // deserialize to Map<String, Object>, while Object would be LinkedHashMap
-                Map<String, Object> examples = new HashMap<>();
+                Map<String, Object> examples = new LinkedHashMap<>();
                 for (NodeTuple tuple : node.getValue()) {
                     examples.put(((ScalarNode) tuple.getKeyNode()).getValue(), constructObject(tuple.getValueNode()));
                 }

packages/http-client-java/generator/http-client-generator-core/src/main/java/com/microsoft/typespec/http/client/generator/core/extension/model/codemodel/OperationGroup.java

@@ -11,7 +11,7 @@
  */
 public class OperationGroup extends Metadata {
     private String $key;
-    private List<Operation> operations = new ArrayList<Operation>();
+    private List<Operation> operations = new ArrayList<>();
     private Client codeModel;
 
     /**

packages/http-client-java/generator/http-client-generator-core/src/main/java/com/microsoft/typespec/http/client/generator/core/extension/model/codemodel/Scheme.java

@@ -4,7 +4,7 @@
 package com.microsoft.typespec.http.client.generator.core.extension.model.codemodel;
 
 import java.util.ArrayList;
-import java.util.HashSet;
+import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Set;
 
@@ -14,7 +14,7 @@
 public class Scheme {
     private Scheme.SecuritySchemeType type;
     // OAuth2
-    private Set<String> scopes = new HashSet<>();
+    private Set<String> scopes = new LinkedHashSet<>();
     private List<OAuth2Flow> flows = new ArrayList<>();
     // Key
     private String name;

packages/http-client-java/generator/http-client-generator-core/src/main/java/com/microsoft/typespec/http/client/generator/core/extension/model/extensionmodel/NextLinkVerb.java

@@ -3,9 +3,6 @@
 
 package com.microsoft.typespec.http.client.generator.core.extension.model.extensionmodel;
 
-import java.util.HashMap;
-import java.util.Map;
-
 /**
  * Represents the HTTP verb for the nextLink operation in pageable settings.
  */
@@ -21,13 +18,6 @@ public enum NextLinkVerb {
     POST("POST");
 
     private final String value;
-    private static final Map<String, NextLinkVerb> CONSTANTS = new HashMap<>();
-
-    static {
-        for (NextLinkVerb v : values()) {
-            CONSTANTS.put(v.value, v);
-        }
-    }
 
     NextLinkVerb(String value) {
         this.value = value;
@@ -55,11 +45,11 @@ public String value() {
      * @throws IllegalArgumentException If the value is not a valid HTTP verb.
      */
     public static NextLinkVerb fromValue(String value) {
-        NextLinkVerb constant = CONSTANTS.get(value);
-        if (constant == null) {
-            throw new IllegalArgumentException(value);
-        } else {
-            return constant;
+        if (GET.value.equals(value)) {
+            return GET;
+        } else if (POST.value.equals(value)) {
+            return POST;
         }
+        throw new IllegalArgumentException(value);
     }
 }

packages/http-client-java/generator/http-client-generator-core/src/main/java/com/microsoft/typespec/http/client/generator/core/extension/plugin/JavaSettings.java

@@ -16,7 +16,7 @@
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
-import java.util.HashMap;
+import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Locale;
 import java.util.Map;
@@ -34,7 +34,7 @@ public class JavaSettings {
     private static JavaSettings instance;
     private static NewPlugin host;
     private static String header;
-    private static final Map<String, Object> SIMPLE_JAVA_SETTINGS = new HashMap<>();
+    private static final Map<String, Object> SIMPLE_JAVA_SETTINGS = new LinkedHashMap<>();
     private static Logger logger;
     private final boolean useKeyCredential;
     private final String flavor;
@@ -70,7 +70,7 @@ static void setHeader(String value) {
         }
     }
 
-    static void setHost(NewPlugin host) {
+    public static void setHost(NewPlugin host) {
         JavaSettings.host = host;
         logger = new PluginLogger(host, JavaSettings.class);
     }
@@ -122,7 +122,7 @@ public static JavaSettings getInstance() {
 
     private static Map<Integer, String> parseStatusCodeMapping(JsonReader jsonReader) throws IOException {
         return jsonReader.readObject(reader -> {
-            Map<Integer, String> mapping = new HashMap<>();
+            Map<Integer, String> mapping = new LinkedHashMap<>();
             while (reader.nextToken() != JsonToken.END_OBJECT) {
                 int key = Integer.parseInt(reader.getFieldName());
                 reader.nextToken();
@@ -649,7 +649,7 @@ public static class ModelerSettings {
          * @param settings The settings that are used by the modeler.
          */
         public ModelerSettings(Map<String, Object> settings) {
-            this.settings = settings == null ? Collections.emptyMap() : settings;
+            this.settings = settings == null ? Map.of() : settings;
         }
 
         /**
@@ -1523,7 +1523,7 @@ public boolean isUseObjectForUnknown() {
         return useObjectForUnknown;
     }
 
-    private final Map<String, String> renameModel = new HashMap<>();
+    private final Map<String, String> renameModel = new LinkedHashMap<>();
 
     public Map<String, String> getJavaNamesForRenameModel() {
         return renameModel;
@@ -1602,7 +1602,7 @@ private static void loadStringOrArraySettingAsArray(String settingName, Consumer
             } else {
                 // Single values will be returned as the string representation.
                 logger.debug("Option, string, {} : {}", settingName, jsonString);
-                action.accept(Collections.singletonList(jsonString));
+                action.accept(List.of(jsonString));
             }
 
             return null;

packages/http-client-java/generator/http-client-generator-core/src/main/java/com/microsoft/typespec/http/client/generator/core/extension/plugin/NewPlugin.java

@@ -15,7 +15,6 @@
 import java.io.StringWriter;
 import java.io.UncheckedIOException;
 import java.util.Arrays;
-import java.util.Collections;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
@@ -192,7 +191,7 @@ public void message(MessageChannel channel, String text, Throwable error, List<S
         Message message = new Message();
         message.setChannel(channel);
         message.setKey(keys);
-        message.setSource(Collections.emptyList());
+        message.setSource(List.of());
         if (error != null) {
             text += "\n" + formatThrowableMessage(error);
         }

packages/http-client-java/generator/http-client-generator-core/src/main/java/com/microsoft/typespec/http/client/generator/core/implementation/ClientModelPropertiesManager.java

@@ -12,7 +12,6 @@
 import io.clientcore.core.utils.CoreUtils;
 import java.util.ArrayList;
 import java.util.Arrays;
-import java.util.Collections;
 import java.util.Iterator;
 import java.util.LinkedHashMap;
 import java.util.LinkedHashSet;
@@ -291,9 +290,8 @@ public ClientModelPropertiesManager(ClientModel model, JavaSettings settings) {
                 + "Add additional possible XmlReader name variables to resolve this issue.");
         }
 
-        this.xmlNamespaceToConstantMapping = model.getXmlName() == null
-            ? Collections.emptyMap()
-            : ClientModelUtil.xmlNamespaceToConstantMapping(model);
+        this.xmlNamespaceToConstantMapping
+            = model.getXmlName() == null ? Map.of() : ClientModelUtil.xmlNamespaceToConstantMapping(model);
     }
 
     private static void superPropertyConsumer(ClientModelProperty property,

packages/http-client-java/generator/http-client-generator-core/src/main/java/com/microsoft/typespec/http/client/generator/core/mapper/ClientMapper.java

@@ -53,10 +53,8 @@
 import io.clientcore.core.utils.CoreUtils;
 import java.util.ArrayList;
 import java.util.Collection;
-import java.util.Collections;
-import java.util.HashMap;
-import java.util.HashSet;
 import java.util.LinkedHashMap;
+import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
@@ -90,7 +88,7 @@ public Client map(CodeModel codeModel) {
 
         // enum model
         final List<EnumType> enumTypes = new ArrayList<>();
-        Set<String> enumNames = new HashSet<>();
+        Set<String> enumNames = new LinkedHashSet<>();
         for (ChoiceSchema choiceSchema : codeModel.getSchemas().getChoices()) {
             IType iType = Mappers.getChoiceMapper().map(choiceSchema);
             if (iType != ClassType.STRING) {
@@ -117,7 +115,7 @@ public Client map(CodeModel codeModel) {
         List<ClientException> exceptions = Stream
             .concat(
                 codeModel.getClients() == null
-                    ? Stream.<OperationGroup>empty()
+                    ? Stream.empty()
                     : codeModel.getClients().stream().flatMap(c -> c.getOperationGroups().stream()),
                 codeModel.getOperationGroups().stream())
             .flatMap(og -> og.getOperations().stream())
@@ -211,7 +209,7 @@ public Client map(CodeModel codeModel) {
 
         // package info
         // client
-        Map<String, PackageInfo> packageInfos = new HashMap<>();
+        Map<String, PackageInfo> packageInfos = new LinkedHashMap<>();
         if (settings.isGenerateClientInterfaces()
             || !settings.isGenerateClientAsImpl()
             || settings.getImplementationSubpackage() == null
@@ -328,10 +326,9 @@ public Client map(CodeModel codeModel) {
                             ? syncClient.getClassName()
                             : asyncClient.getClassName().replace("AsyncClient", "Client"));
                         String clientBuilderName = clientName + builderSuffix;
-                        ClientBuilder clientBuilder
-                            = new ClientBuilder(builderPackage, clientBuilderName, serviceClient,
-                                (syncClient == null) ? Collections.emptyList() : Collections.singletonList(syncClient),
-                                Collections.singletonList(asyncClient), serviceClient.getCrossLanguageDefinitionId());
+                        ClientBuilder clientBuilder = new ClientBuilder(builderPackage, clientBuilderName,
+                            serviceClient, (syncClient == null) ? List.of() : List.of(syncClient), List.of(asyncClient),
+                            serviceClient.getCrossLanguageDefinitionId());
 
                         addBuilderTraits(clientBuilder, serviceClient);
                         clientBuilders.add(clientBuilder);
@@ -381,7 +378,7 @@ public Client map(CodeModel codeModel) {
     private void addConvenienceExamples(Client.Builder builder, List<AsyncSyncClient> syncClients) {
         // convenience examples
         List<ClientMethodExample> convenienceExamples = new ArrayList<>();
-        Set<String> convenienceExampleNameSet = new HashSet<>();
+        Set<String> convenienceExampleNameSet = new LinkedHashSet<>();
 
         BiConsumer<AsyncSyncClient, ConvenienceMethod> handleConvenienceExample = (c, convenienceMethod) -> {
             ClientBuilder clientBuilder = c.getClientBuilder();
@@ -419,7 +416,7 @@ private void addConvenienceExamples(Client.Builder builder, List<AsyncSyncClient
 
     private void addProtocolExamples(Client.Builder builder, List<AsyncSyncClient> syncClients) {
         List<ProtocolExample> protocolExamples = new ArrayList<>();
-        Set<String> protocolExampleNameSet = new HashSet<>();
+        Set<String> protocolExampleNameSet = new LinkedHashSet<>();
 
         BiConsumer<AsyncSyncClient, ClientMethod> handleExample = (c, m) -> {
             if (m.getMethodVisibility() == JavaVisibility.Public
@@ -445,7 +442,7 @@ private void addProtocolExamples(Client.Builder builder, List<AsyncSyncClient> s
 
         // protocol examples, exclude those that have convenience methods
         syncClients.stream().filter(c -> c.getServiceClient() != null).forEach(c -> {
-            Set<String> convenienceProxyMethodNames = new HashSet<>();
+            Set<String> convenienceProxyMethodNames = new LinkedHashSet<>();
             if (c.getConvenienceMethods() != null) {
                 convenienceProxyMethodNames.addAll(c.getConvenienceMethods()
                     .stream()
@@ -459,7 +456,7 @@ private void addProtocolExamples(Client.Builder builder, List<AsyncSyncClient> s
                 .forEach(m -> handleExample.accept(c, m));
         });
         syncClients.stream().filter(c -> c.getMethodGroupClient() != null).forEach(c -> {
-            Set<String> convenienceProxyMethodNames = new HashSet<>();
+            Set<String> convenienceProxyMethodNames = new LinkedHashSet<>();
             if (c.getConvenienceMethods() != null) {
                 convenienceProxyMethodNames.addAll(c.getConvenienceMethods()
                     .stream()
@@ -484,7 +481,7 @@ private void addProtocolExamples(Client.Builder builder, List<AsyncSyncClient> s
     protected Map<ServiceClient, com.microsoft.typespec.http.client.generator.core.extension.model.codemodel.Client>
         processClients(List<com.microsoft.typespec.http.client.generator.core.extension.model.codemodel.Client> clients,
             CodeModel codeModel) {
-        return Collections.emptyMap();
+        return Map.of();
     }
 
     private void addBuilderTraits(ClientBuilder clientBuilder, ServiceClient serviceClient) {
@@ -564,9 +561,9 @@ public ObjectSchema parseHeader(Operation operation, JavaSettings settings) {
 
         String name = CodeNamer.getPlural(operation.getOperationGroup().getLanguage().getJava().getName())
             + CodeNamer.toPascalCase(operation.getLanguage().getJava().getName()) + "Headers";
-        Map<String, Schema> headerMap = new HashMap<>();
-        Map<String, String> headerClientNameMap = new HashMap<>();
-        Map<String, XmsExtensions> headerExtensions = new HashMap<>();
+        Map<String, Schema> headerMap = new LinkedHashMap<>();
+        Map<String, String> headerClientNameMap = new LinkedHashMap<>();
+        Map<String, XmsExtensions> headerExtensions = new LinkedHashMap<>();
         for (Response response : operation.getResponses()) {
             if (response.getProtocol().getHttp().getHeaders() != null) {
                 for (Header header : response.getProtocol().getHttp().getHeaders()) {
@@ -585,7 +582,7 @@ public ObjectSchema parseHeader(Operation operation, JavaSettings settings) {
         headerSchema.getLanguage().getJava().setName(name);
         headerSchema.setProperties(new ArrayList<>());
         headerSchema.setStronglyTypedHeader(true);
-        headerSchema.setUsage(new HashSet<>(Collections.singletonList(SchemaContext.OUTPUT)));
+        headerSchema.setUsage(new LinkedHashSet<>(List.of(SchemaContext.OUTPUT)));
 
         // TODO (weidxu): at present we do not generate convenience API with Header model
 //        if (operation.getConvenienceApi() != null) {
@@ -697,7 +694,7 @@ private static ModuleInfo getModuleInfo(List<String> modelsPackages, Collection<
     protected List<String> getModelsPackages(List<ClientModel> clientModels, List<EnumType> enumTypes,
         List<ClientResponse> responseModels) {
 
-        List<String> ret = Collections.emptyList();
+        List<String> ret = List.of();
 
         JavaSettings settings = JavaSettings.getInstance();
         boolean hasModels = !settings.isDataPlaneClient()   // not DPG

packages/http-client-java/generator/http-client-generator-core/src/main/java/com/microsoft/typespec/http/client/generator/core/mapper/ClientMethodParameterProcessor.java

@@ -14,7 +14,7 @@
 import com.microsoft.typespec.http.client.generator.core.model.clientmodel.ProxyMethodParameter;
 import com.microsoft.typespec.http.client.generator.core.util.MethodUtil;
 import java.util.ArrayList;
-import java.util.HashMap;
+import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.stream.Collectors;
@@ -28,7 +28,7 @@ static ClientMethodParametersDetails process(Request request, boolean mapFluxByt
         final List<Parameter> codeModelParameters = getCodeModelParameters(request, isProtocolMethod);
         final List<ParametersTuple> parametersTuples = new ArrayList<>();
         final List<String> requiredNullableParameterExpressions = new ArrayList<>();
-        final Map<String, String> validateParameterExpressions = new HashMap<>();
+        final Map<String, String> validateParameterExpressions = new LinkedHashMap<>();
         final boolean isJsonPatch = MethodUtil.isContentTypeInRequest(request, "application/json-patch+json");
 
         final ParametersTransformationProcessor transformationProcessor