Generate *ProtoFields classes instead of value objects.

pom.xml

@@ -50,6 +50,8 @@
     <module>wire-maven-plugin</module>
     <module>wire-runtime</module>
     <module>wire-schema</module>
+    <module>wire-schema-tests</module>
+    <module>wire-testing</module>
   </modules>
 
   <properties>
@@ -104,7 +106,6 @@
         <groupId>com.google.jimfs</groupId>
         <artifactId>jimfs</artifactId>
         <version>1.0</version>
-        <scope>test</scope>
       </dependency>
     </dependencies>
   </dependencyManagement>

wire-compiler/src/main/java/com/squareup/wire/WireCompiler.java

@@ -15,13 +15,17 @@
  */
 package com.squareup.wire;
 
+import com.google.common.collect.ImmutableMap;
 import com.squareup.javapoet.ClassName;
 import com.squareup.javapoet.JavaFile;
+import com.squareup.javapoet.TypeName;
 import com.squareup.javapoet.TypeSpec;
+import com.squareup.wire.java.AdapterConstant;
 import com.squareup.wire.java.JavaGenerator;
 import com.squareup.wire.schema.IdentifierSet;
 import com.squareup.wire.schema.Location;
 import com.squareup.wire.schema.ProtoFile;
+import com.squareup.wire.schema.ProtoType;
 import com.squareup.wire.schema.Schema;
 import com.squareup.wire.schema.SchemaLoader;
 import com.squareup.wire.schema.Type;
@@ -33,7 +37,9 @@
 import java.nio.file.Path;
 import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.LinkedHashMap;
 import java.util.List;
+import java.util.Map;
 import java.util.Scanner;
 import java.util.concurrent.Callable;
 import java.util.concurrent.ConcurrentLinkedQueue;
@@ -94,6 +100,7 @@ public final class WireCompiler {
   public static final String NAMED_FILES_ONLY = "--named_files_only";
   public static final String ANDROID = "--android";
   public static final String COMPACT = "--compact";
+  public static final String PROTO_ADAPTER = "--proto_adapter=";
   public static final int MAX_WRITE_CONCURRENCY = 8;
 
   private static final String CODE_GENERATED_BY_WIRE =
@@ -111,10 +118,14 @@ public final class WireCompiler {
   final boolean namedFilesOnly;
   final boolean emitAndroid;
   final boolean emitCompact;
+  final ImmutableMap<ProtoType, ClassName> protoTypeToJavaClassName;
+  final ImmutableMap<ProtoType, AdapterConstant> protoTypeToAdapterConstant;
 
   WireCompiler(FileSystem fs, WireLogger log, List<String> protoPaths, String javaOut,
       List<String> sourceFileNames, IdentifierSet identifierSet, boolean dryRun,
-      boolean namedFilesOnly, boolean emitAndroid, boolean emitCompact) {
+      boolean namedFilesOnly, boolean emitAndroid, boolean emitCompact,
+      Map<ProtoType, ClassName> protoTypeToJavaClassName,
+      Map<ProtoType, AdapterConstant> protoTypeToAdapterConstant) {
     this.fs = fs;
     this.log = log;
     this.protoPaths = protoPaths;
@@ -125,6 +136,8 @@ public final class WireCompiler {
     this.namedFilesOnly = namedFilesOnly;
     this.emitAndroid = emitAndroid;
     this.emitCompact = emitCompact;
+    this.protoTypeToJavaClassName = ImmutableMap.copyOf(protoTypeToJavaClassName);
+    this.protoTypeToAdapterConstant = ImmutableMap.copyOf(protoTypeToAdapterConstant);
   }
 
   public static void main(String... args) throws IOException {
@@ -153,6 +166,8 @@ static WireCompiler forArgs(
     boolean namedFilesOnly = false;
     boolean emitAndroid = false;
     boolean emitCompact = false;
+    Map<ProtoType, ClassName> protoTypeToJavaClass = new LinkedHashMap<>();
+    Map<ProtoType, AdapterConstant> protoTypeToAdapter = new LinkedHashMap<>();
 
     for (String arg : args) {
       if (arg.startsWith(PROTO_PATH_FLAG)) {
@@ -176,6 +191,18 @@ static WireCompiler forArgs(
         for (String identifier : splitArg(arg, EXCLUDES_FLAG.length())) {
           identifierSetBuilder.exclude(identifier);
         }
+      } else if (arg.startsWith(PROTO_ADAPTER)) {
+        List<String> customProtoAdapterArgs = splitArg(arg, PROTO_ADAPTER.length());
+        if (customProtoAdapterArgs.size() != 3) {
+          throw new IllegalArgumentException(
+              "Expected <proto type>,<class name>,<adapter constant> but was " + arg);
+        }
+
+        ProtoType protoType = ProtoType.get(customProtoAdapterArgs.get(0).trim());
+        ClassName javaClassName = ClassName.bestGuess(customProtoAdapterArgs.get(1).trim());
+
+        protoTypeToJavaClass.put(protoType, javaClassName);
+        protoTypeToAdapter.put(protoType, new AdapterConstant(customProtoAdapterArgs.get(2).trim()));
       } else if (arg.equals(QUIET_FLAG)) {
         quiet = true;
       } else if (arg.equals(DRY_RUN_FLAG)) {
@@ -200,7 +227,8 @@ static WireCompiler forArgs(
     logger.setQuiet(quiet);
 
     return new WireCompiler(fileSystem, logger, protoPaths, javaOut, sourceFileNames,
-        identifierSetBuilder.build(), dryRun, namedFilesOnly, emitAndroid, emitCompact);
+        identifierSetBuilder.build(), dryRun, namedFilesOnly, emitAndroid, emitCompact,
+        protoTypeToJavaClass, protoTypeToAdapter);
   }
 
   private static List<String> splitArg(String arg, int flagLength) {
@@ -229,6 +257,7 @@ void compile() throws IOException {
     }
 
     JavaGenerator javaGenerator = JavaGenerator.get(schema)
+        .withCustomProtoAdapter(protoTypeToJavaClassName, protoTypeToAdapterConstant)
         .withAndroid(emitAndroid)
         .withCompact(emitCompact);
 
@@ -277,7 +306,11 @@ public Void call() throws IOException {
         }
 
         TypeSpec typeSpec = javaGenerator.generateType(type);
-        ClassName javaTypeName = (ClassName) javaGenerator.typeName(type.type());
+        TypeName typeName = javaGenerator.protoFieldsTypeName(type.type());
+        if (typeName == null) {
+          typeName = javaGenerator.typeName(type.type());
+        }
+        ClassName javaTypeName = (ClassName) typeName;
         Location location = type.location();
 
         JavaFile.Builder builder = JavaFile.builder(javaTypeName.packageName(), typeSpec)

wire-java-generator/pom.xml

@@ -35,6 +35,12 @@
       <artifactId>javapoet</artifactId>
     </dependency>
 
+    <dependency>
+      <groupId>com.squareup.wire</groupId>
+      <artifactId>wire-testing</artifactId>
+      <version>${project.version}</version>
+      <scope>test</scope>
+    </dependency>
     <dependency>
       <groupId>junit</groupId>
       <artifactId>junit</artifactId>

wire-java-generator/src/main/java/com/squareup/wire/java/AdapterConstant.java

@@ -0,0 +1,43 @@
+/*
+ * Copyright (C) 2016 Square, Inc.
+ *
+ * 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.squareup.wire.java;
+
+import com.squareup.javapoet.ClassName;
+import com.squareup.wire.ProtoAdapter;
+
+/**
+ * A constant field that identifies a {@link ProtoAdapter}. This should be a string like like {@code
+ * com.squareup.dinosaurs.Dinosaur#ADAPTER} with a fully qualified class name, a {@code #}, and a
+ * field name.
+ */
+public final class AdapterConstant {
+  public final ClassName className;
+  public final String adapterName;
+
+  public AdapterConstant(ClassName className, String adapterName) {
+    this.className = className;
+    this.adapterName = adapterName;
+  }
+
+  public AdapterConstant(String adapter) {
+    String[] names = adapter.split("#");
+    if (names.length != 2) {
+      throw new IllegalArgumentException("Illegally formatted adapter: " + adapter + ".");
+    }
+    this.className = ClassName.bestGuess(names[0]);
+    this.adapterName = names[1];
+  }
+}