Use Java 11 collections conveniences everywhere

client/rest-high-level/src/main/java/org/elasticsearch/client/ml/filestructurefinder/FileStructure.java

@@ -25,7 +25,6 @@
 import org.elasticsearch.common.xcontent.XContentParser;
 
 import java.io.IOException;
-import java.util.ArrayList;
 import java.util.Collections;
 import java.util.LinkedHashMap;
 import java.util.List;
@@ -148,22 +147,20 @@ private FileStructure(int numLinesAnalyzed, int numMessagesAnalyzed, String samp
         this.format = Objects.requireNonNull(format);
         this.multilineStartPattern = multilineStartPattern;
         this.excludeLinesPattern = excludeLinesPattern;
-        this.columnNames = (columnNames == null) ? null : Collections.unmodifiableList(new ArrayList<>(columnNames));
+        this.columnNames = (columnNames == null) ? null : List.copyOf(columnNames);
         this.hasHeaderRow = hasHeaderRow;
         this.delimiter = delimiter;
         this.quote = quote;
         this.shouldTrimFields = shouldTrimFields;
         this.grokPattern = grokPattern;
         this.timestampField = timestampField;
-        this.jodaTimestampFormats =
-            (jodaTimestampFormats == null) ? null : Collections.unmodifiableList(new ArrayList<>(jodaTimestampFormats));
-        this.javaTimestampFormats =
-            (javaTimestampFormats == null) ? null : Collections.unmodifiableList(new ArrayList<>(javaTimestampFormats));
+        this.jodaTimestampFormats = (jodaTimestampFormats == null) ? null : List.copyOf(jodaTimestampFormats);
+        this.javaTimestampFormats = (javaTimestampFormats == null) ? null : List.copyOf(javaTimestampFormats);
         this.needClientTimezone = needClientTimezone;
         this.mappings = Collections.unmodifiableSortedMap(new TreeMap<>(mappings));
         this.ingestPipeline = (ingestPipeline == null) ? null : Collections.unmodifiableMap(new LinkedHashMap<>(ingestPipeline));
         this.fieldStats = Collections.unmodifiableSortedMap(new TreeMap<>(fieldStats));
-        this.explanation = (explanation == null) ? null : Collections.unmodifiableList(new ArrayList<>(explanation));
+        this.explanation = (explanation == null) ? null : List.copyOf(explanation);
     }
 
     public int getNumLinesAnalyzed() {

client/rest-high-level/src/main/java/org/elasticsearch/client/security/GetPrivilegesResponse.java

@@ -26,7 +26,6 @@
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Collection;
-import java.util.Collections;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Objects;
@@ -44,7 +43,7 @@ public Set<ApplicationPrivilege> getPrivileges() {
     }
 
     public GetPrivilegesResponse(Collection<ApplicationPrivilege> privileges) {
-        this.privileges = Collections.unmodifiableSet(new HashSet<>(privileges));
+        this.privileges = Set.copyOf(privileges);
     }
 
     public static GetPrivilegesResponse fromXContent(XContentParser parser) throws IOException {

client/rest-high-level/src/main/java/org/elasticsearch/client/security/GetUsersResponse.java

@@ -27,9 +27,9 @@
 import org.elasticsearch.common.xcontent.XContentParserUtils;
 
 import java.io.IOException;
-import java.util.Collection;
 import java.util.Collections;
 import java.util.HashSet;
+import java.util.List;
 import java.util.Map;
 import java.util.Objects;
 import java.util.Set;
@@ -99,7 +99,7 @@ public int hashCode() {
         (constructorObjects) -> {
             int i = 0;
             final String username = (String) constructorObjects[i++];
-            final Collection<String> roles = (Collection<String>) constructorObjects[i++];
+            final List<String> roles = (List<String>) constructorObjects[i++];
             final Map<String, Object> metadata = (Map<String, Object>) constructorObjects[i++];
             final Boolean enabled = (Boolean) constructorObjects[i++];
             final String fullName = (String) constructorObjects[i++];
@@ -120,13 +120,13 @@ protected static final class ParsedUser {
         protected User user;
         protected boolean enabled;
 
-        public ParsedUser(String username, Collection<String> roles, Map<String, Object> metadata, Boolean enabled,
+        public ParsedUser(String username, List<String> roles, Map<String, Object> metadata, Boolean enabled,
                           @Nullable String fullName, @Nullable String email) {
-            String checkedUsername = username = Objects.requireNonNull(username, "`username` is required, cannot be null");
-            Collection<String> checkedRoles = Collections.unmodifiableSet(new HashSet<>(
-                Objects.requireNonNull(roles, "`roles` is required, cannot be null. Pass an empty Collection instead.")));
-            Map<String, Object> checkedMetadata = Collections
-                .unmodifiableMap(Objects.requireNonNull(metadata, "`metadata` is required, cannot be null. Pass an empty map instead."));
+            String checkedUsername = Objects.requireNonNull(username, "`username` is required, cannot be null");
+            List<String> checkedRoles =
+                    List.copyOf(Objects.requireNonNull(roles, "`roles` is required, cannot be null. Pass an empty Collection instead."));
+            Map<String, Object> checkedMetadata = Collections.unmodifiableMap(
+                    Objects.requireNonNull(metadata, "`metadata` is required, cannot be null. Pass an empty map instead."));
             this.user = new User(checkedUsername, checkedRoles, checkedMetadata, fullName, email);
             this.enabled = enabled;
         }

client/rest-high-level/src/main/java/org/elasticsearch/client/security/support/expressiondsl/expressions/CompositeRoleMapperExpression.java

@@ -23,8 +23,6 @@
 import org.elasticsearch.common.xcontent.XContentBuilder;
 
 import java.io.IOException;
-import java.util.Arrays;
-import java.util.Collections;
 import java.util.List;
 import java.util.Objects;
 
@@ -53,7 +51,7 @@ public abstract class CompositeRoleMapperExpression implements RoleMapperExpress
         assert name != null : "field name cannot be null";
         assert elements != null : "at least one field expression is required";
         this.name = name;
-        this.elements = Collections.unmodifiableList(Arrays.asList(elements));
+        this.elements = List.of(elements);
     }
 
     public String getName() {

client/rest-high-level/src/main/java/org/elasticsearch/client/security/support/expressiondsl/fields/FieldRoleMapperExpression.java

@@ -23,8 +23,6 @@
 import org.elasticsearch.common.xcontent.XContentBuilder;
 
 import java.io.IOException;
-import java.util.Arrays;
-import java.util.Collections;
 import java.util.List;
 import java.util.Objects;
 
@@ -53,7 +51,7 @@ public FieldRoleMapperExpression(final String field, final Object... values) {
             throw new IllegalArgumentException("null or empty values for field (" + field + ")");
         }
         this.field = field;
-        this.values = Collections.unmodifiableList(Arrays.asList(values));
+        this.values = List.of(values);
     }
 
     public String getField() {

client/rest-high-level/src/main/java/org/elasticsearch/client/security/user/User.java

@@ -22,12 +22,10 @@
 import org.elasticsearch.common.Nullable;
 import org.elasticsearch.common.Strings;
 
-import java.util.Collection;
 import java.util.Collections;
-import java.util.HashSet;
+import java.util.List;
 import java.util.Map;
 import java.util.Objects;
-import java.util.Set;
 
 /**
  * A user to be utilized with security APIs.
@@ -36,7 +34,7 @@
 public final class User {
 
     private final String username;
-    private final Set<String> roles;
+    private final List<String> roles;
     private final Map<String, Object> metadata;
     @Nullable private final String fullName;
     @Nullable private final String email;
@@ -50,13 +48,12 @@ public final class User {
      * @param fullName the full name of the user that may be used for display purposes
      * @param email the email address of the user
      */
-    public User(String username, Collection<String> roles, Map<String, Object> metadata, @Nullable String fullName,
+    public User(String username, List<String> roles, Map<String, Object> metadata, @Nullable String fullName,
             @Nullable String email) {
-        this.username = username = Objects.requireNonNull(username, "`username` is required, cannot be null");
-        this.roles = Collections.unmodifiableSet(new HashSet<>(
-                Objects.requireNonNull(roles, "`roles` is required, cannot be null. Pass an empty Collection instead.")));
-        this.metadata = Collections
-                .unmodifiableMap(Objects.requireNonNull(metadata, "`metadata` is required, cannot be null. Pass an empty map instead."));
+        this.username = Objects.requireNonNull(username, "`username` is required, cannot be null");
+        this.roles = List.copyOf(Objects.requireNonNull(roles, "`roles` is required, cannot be null. Pass an empty Collection instead."));
+        this.metadata = Collections.unmodifiableMap(
+                Objects.requireNonNull(metadata, "`metadata` is required, cannot be null. Pass an empty map instead."));
         this.fullName = fullName;
         this.email = email;
     }
@@ -67,7 +64,7 @@ public User(String username, Collection<String> roles, Map<String, Object> metad
      * @param username the username, also known as the principal, unique for in the scope of a realm
      * @param roles the roles that this user is assigned
      */
-    public User(String username, Collection<String> roles) {
+    public User(String username, List<String> roles) {
         this(username, roles, Collections.emptyMap(), null, null);
     }
 
@@ -84,7 +81,7 @@ public String getUsername() {
      *          identified by their unique names and each represents as
      *          set of permissions. Can never be {@code null}.
      */
-    public Set<String> getRoles() {
+    public List<String> getRoles() {
         return this.roles;
     }
 

client/rest-high-level/src/main/java/org/elasticsearch/client/security/user/privileges/AbstractIndicesPrivileges.java

@@ -31,7 +31,7 @@
 import java.io.UncheckedIOException;
 import java.util.Collection;
 import java.util.Collections;
-import java.util.HashSet;
+import java.util.List;
 import java.util.Objects;
 import java.util.Set;
 
@@ -44,8 +44,8 @@ public abstract class AbstractIndicesPrivileges {
     static final ParseField FIELD_PERMISSIONS = new ParseField("field_security");
     static final ParseField QUERY = new ParseField("query");
 
-    protected final Set<String> indices;
-    protected final Set<String> privileges;
+    protected final List<String> indices;
+    protected final List<String> privileges;
     protected final boolean allowRestrictedIndices;
 
     AbstractIndicesPrivileges(Collection<String> indices, Collection<String> privileges, boolean allowRestrictedIndices) {
@@ -55,15 +55,15 @@ public abstract class AbstractIndicesPrivileges {
         if (null == privileges || privileges.isEmpty()) {
             throw new IllegalArgumentException("indices privileges must define at least one privilege");
         }
-        this.indices = Collections.unmodifiableSet(new HashSet<>(indices));
-        this.privileges = Collections.unmodifiableSet(new HashSet<>(privileges));
+        this.indices = List.copyOf(indices);
+        this.privileges = List.copyOf(privileges);
         this.allowRestrictedIndices = allowRestrictedIndices;
     }
 
     /**
      * The indices names covered by the privileges.
      */
-    public Set<String> getIndices() {
+    public List<String> getIndices() {
         return this.indices;
     }
 
@@ -72,7 +72,7 @@ public Set<String> getIndices() {
      * such privileges, but the {@code String} datatype allows for flexibility in defining
      * finer grained privileges.
      */
-    public Set<String> getPrivileges() {
+    public List<String> getPrivileges() {
         return this.privileges;
     }
 
@@ -127,9 +127,9 @@ static FieldSecurity parse(XContentParser parser, Void context) throws IOExcepti
 
         FieldSecurity(Collection<String> grantedFields, Collection<String> deniedFields) {
             // unspecified granted fields means no restriction
-            this.grantedFields = grantedFields == null ? null : Collections.unmodifiableSet(new HashSet<>(grantedFields));
+            this.grantedFields = grantedFields == null ? null : Set.copyOf(grantedFields);
             // unspecified denied fields means no restriction
-            this.deniedFields = deniedFields == null ? null : Collections.unmodifiableSet(new HashSet<>(deniedFields));
+            this.deniedFields = deniedFields == null ? null : Set.copyOf(deniedFields);
         }
 
         /**

client/rest-high-level/src/main/java/org/elasticsearch/client/security/user/privileges/ApplicationPrivilege.java

@@ -29,14 +29,11 @@
 import org.elasticsearch.common.xcontent.XContentParser;
 
 import java.io.IOException;
-
 import java.util.Arrays;
-import java.util.Collection;
 import java.util.Collections;
-import java.util.HashSet;
+import java.util.List;
 import java.util.Map;
 import java.util.Objects;
-import java.util.Set;
 
 import static org.elasticsearch.common.xcontent.ConstructingObjectParser.constructorArg;
 import static org.elasticsearch.common.xcontent.ConstructingObjectParser.optionalConstructorArg;
@@ -55,10 +52,10 @@ public final class ApplicationPrivilege implements ToXContentObject {
 
     private final String application;
     private final String name;
-    private final Set<String> actions;
+    private final List<String> actions;
     private final Map<String, Object> metadata;
 
-    public ApplicationPrivilege(String application, String name, Collection<String> actions, @Nullable Map<String, Object> metadata) {
+    public ApplicationPrivilege(String application, String name, List<String> actions, @Nullable Map<String, Object> metadata) {
         if (Strings.isNullOrEmpty(application)) {
             throw new IllegalArgumentException("application name must be provided");
         } else {
@@ -72,12 +69,12 @@ public ApplicationPrivilege(String application, String name, Collection<String>
         if (actions == null || actions.isEmpty()) {
             throw new IllegalArgumentException("actions must be provided");
         } else {
-            this.actions = Collections.unmodifiableSet(new HashSet<>(actions));
+            this.actions = List.copyOf(actions);
         }
         if (metadata == null || metadata.isEmpty()) {
             this.metadata = Collections.emptyMap();
         } else {
-            this.metadata = Collections.unmodifiableMap(metadata);
+            this.metadata = Map.copyOf(metadata);
         }
     }
 
@@ -89,7 +86,7 @@ public String getName() {
         return name;
     }
 
-    public Set<String> getActions() {
+    public List<String> getActions() {
         return actions;
     }
 
@@ -100,7 +97,7 @@ public Map<String, Object> getMetadata() {
     @SuppressWarnings("unchecked")
     public static final ConstructingObjectParser<ApplicationPrivilege, String> PARSER = new ConstructingObjectParser<>(
         "application_privilege",
-        true, args -> new ApplicationPrivilege((String) args[0], (String) args[1], (Collection<String>) args[2],
+        true, args -> new ApplicationPrivilege((String) args[0], (String) args[1], (List<String>) args[2],
         (Map<String, Object>) args[3]));
 
     static {
@@ -137,7 +134,7 @@ public static Builder builder() {
     public static final class Builder {
         private String applicationName = null;
         private String privilegeName = null;
-        private Collection<String> actions = null;
+        private List<String> actions = null;
         private Map<String, Object> metadata = null;
 
         private Builder() {
@@ -158,7 +155,7 @@ public Builder actions(String... actions) {
             return this;
         }
 
-        public Builder actions(Collection<String> actions) {
+        public Builder actions(List<String> actions) {
             this.actions = Objects.requireNonNull(actions);
             return this;
         }

client/rest-high-level/src/main/java/org/elasticsearch/client/security/user/privileges/ApplicationResourcePrivileges.java

@@ -29,11 +29,8 @@
 import org.elasticsearch.common.xcontent.XContentType;
 
 import java.io.IOException;
-import java.util.Collection;
-import java.util.Collections;
-import java.util.HashSet;
+import java.util.List;
 import java.util.Objects;
-import java.util.Set;
 
 import static org.elasticsearch.common.xcontent.ConstructingObjectParser.constructorArg;
 
@@ -57,8 +54,8 @@ public final class ApplicationResourcePrivileges implements ToXContentObject {
                 // end up being implicitly set to null in that request.
                 int i = 0;
                 final String application = (String) constructorObjects[i++];
-                final Collection<String> privileges = (Collection<String>) constructorObjects[i++];
-                final Collection<String> resources = (Collection<String>) constructorObjects[i];
+                final List<String> privileges = (List<String>) constructorObjects[i++];
+                final List<String> resources = (List<String>) constructorObjects[i];
                 return new ApplicationResourcePrivileges(application, privileges, resources);
             });
 
@@ -69,8 +66,8 @@ public final class ApplicationResourcePrivileges implements ToXContentObject {
     }
 
     private final String application;
-    private final Set<String> privileges;
-    private final Set<String> resources;
+    private final List<String> privileges;
+    private final List<String> resources;
 
     /**
      * Constructs privileges for resources under an application scope.
@@ -85,7 +82,7 @@ public final class ApplicationResourcePrivileges implements ToXContentObject {
      *            The resources names. Cannot be null or empty. Resource identifiers
      *            are completely under the clients control.
      */
-    public ApplicationResourcePrivileges(String application, Collection<String> privileges, Collection<String> resources) {
+    public ApplicationResourcePrivileges(String application, List<String> privileges, List<String> resources) {
         if (Strings.isNullOrEmpty(application)) {
             throw new IllegalArgumentException("application privileges must have an application name");
         }
@@ -96,19 +93,19 @@ public ApplicationResourcePrivileges(String application, Collection<String> priv
             throw new IllegalArgumentException("application privileges must refer to at least one resource");
         }
         this.application = application;
-        this.privileges = Collections.unmodifiableSet(new HashSet<>(privileges));
-        this.resources = Collections.unmodifiableSet(new HashSet<>(resources));
+        this.privileges = List.copyOf(privileges);
+        this.resources = List.copyOf(resources);
     }
 
     public String getApplication() {
         return application;
     }
 
-    public Set<String> getResources() {
+    public List<String> getResources() {
         return this.resources;
     }
 
-    public Set<String> getPrivileges() {
+    public List<String> getPrivileges() {
         return this.privileges;
     }