<feature/nested_field> Implemented mapping generation for nested fields

Author: devindi

processor/src/main/java/com/devindi/mapper/MapperGenerator.java

@@ -2,6 +2,8 @@
 
 import com.squareup.javapoet.ClassName;
 import com.squareup.javapoet.MethodSpec;
+import com.squareup.javapoet.ParameterSpec;
+import com.squareup.javapoet.TypeName;
 import com.squareup.javapoet.TypeSpec;
 
 import java.util.ArrayList;
@@ -34,11 +36,13 @@ static MapperGenerator create(TypeElement element, ProcessingEnvironment env) {
     private final TypeElement element;
     private final ProcessingEnvironment processingEnv;
     private List<MappingInfo> mappings;
+    private List<MappingInfo> autoMappings;
 
     private MapperGenerator(TypeElement mapperElement, ProcessingEnvironment processingEnvironment) {
         this.processingEnv = processingEnvironment;
         this.element = mapperElement;
         mappings = new ArrayList<>();
+        autoMappings = new ArrayList<>();
     }
 
     public TypeSpec generate() {
@@ -53,6 +57,12 @@ public TypeSpec generate() {
             implBuilder.addMethod(methodSpec);
         }
 
+        for (MappingInfo autoMapping : autoMappings) {
+            MethodSpec methodSpec = generateMappingMethod(autoMapping);
+            implBuilder.addMethod(methodSpec);
+        }
+
+
         return implBuilder.build();
     }
 
@@ -77,7 +87,8 @@ private MethodSpec generateMappingMethod(MappingInfo mapping) {
             processingEnv.getMessager().printMessage(Diagnostic.Kind.MANDATORY_WARNING, "Target constructor have different arguments count", mapping.getMethod());
         }
 
-        MethodSpec.Builder methodBuilder = MethodSpec.overriding(mapping.getMethod());
+
+        MethodSpec.Builder methodBuilder = createMethodBuilder(mapping);
         StringBuilder statementBuilder = new StringBuilder();
         statementBuilder
                 .append("return new ")
@@ -86,19 +97,7 @@ private MethodSpec generateMappingMethod(MappingInfo mapping) {
 
         String separator = "";
         for (VariableElement constructorParameter : constructorParameters) {
-            String sourceFieldName = constructorParameter.getSimpleName().toString().toLowerCase();
-            com.devindi.mapper.Mapping annotation = mapping.getMethod().getAnnotation(com.devindi.mapper.Mapping.class);
-            if (annotation != null && annotation.target().toLowerCase().equals(constructorParameter.getSimpleName().toString().toLowerCase())) {
-                sourceFieldName = annotation.source();
-            }
-            Mappings mappings = mapping.getMethod().getAnnotation(Mappings.class);
-            if (mappings != null) {
-                for (com.devindi.mapper.Mapping fieldMapping : mappings.value()) {
-                    if (fieldMapping != null && fieldMapping.target().toLowerCase().equals(constructorParameter.getSimpleName().toString().toLowerCase())) {
-                        sourceFieldName = fieldMapping.source();
-                    }
-                }
-            }
+            String sourceFieldName = mapping.getSourceFieldName(constructorParameter.getSimpleName().toString().toLowerCase());
             ExecutableElement getter = argumentGetters.get(sourceFieldName.toLowerCase());
             if (getter == null) {
                 processingEnv.getMessager().printMessage(Diagnostic.Kind.ERROR, "Failed to find getter at source for target field", constructorParameter);
@@ -108,27 +107,26 @@ private MethodSpec generateMappingMethod(MappingInfo mapping) {
                 //getter and constructor parameter have different types
                 MappingInfo depMapping = findMapping(getter.getReturnType(), constructorParameter.asType());
                 if (depMapping == null) {
-                    // TODO: 06.09.17 generate method
-                    processingEnv.getMessager().printMessage(Diagnostic.Kind.ERROR, "Getter return type and constructor argument type are different", mapping.getMethod());
-                } else {
-                    statementBuilder
-                            .append(separator)
-                            .append('\n')
-                            .append("this.")
-                            .append(depMapping.getMethod().getSimpleName())
-                            .append("(")
-                    .append(mapping.getMethod().getParameters().get(0).getSimpleName())
-                            .append(".")
-                            .append(getter.getSimpleName())
-                            .append("()")
-                    .append(")");
-                    separator = ",";
+                    depMapping = new MappingInfo(getter.getReturnType(), constructorParameter.asType());
+                    autoMappings.add(depMapping);
                 }
+                statementBuilder
+                        .append(separator)
+                        .append('\n')
+                        .append("this.")
+                        .append(depMapping.getMethodName())
+                        .append("(")
+                        .append(mapping.getSourceName())
+                        .append(".")
+                        .append(getter.getSimpleName())
+                        .append("()")
+                        .append(")");
+                separator = ",";
             } else {
                 statementBuilder
                         .append(separator)
                         .append('\n')
-                        .append(mapping.getMethod().getParameters().get(0).getSimpleName())
+                        .append(mapping.getSourceName())
                         .append(".")
                         .append(getter.getSimpleName())
                         .append("()");
@@ -141,8 +139,6 @@ private MethodSpec generateMappingMethod(MappingInfo mapping) {
                 .append(")");
         methodBuilder.addStatement(statementBuilder.toString());
 
-
-
         return methodBuilder.build();
     }
 
@@ -175,7 +171,15 @@ private MappingInfo findMapping(TypeMirror source, TypeMirror target) {
         return null;
     }
 
-    private MappingInfo generateMapping(TypeMirror source, TypeMirror target) {
-        return null;
+    private MethodSpec.Builder createMethodBuilder(MappingInfo info) {
+        ExecutableElement method = info.getMethod();
+        if (method == null) {
+            MethodSpec.Builder builder = MethodSpec.methodBuilder(info.getMethodName().toString());
+            builder.addModifiers(Modifier.PRIVATE);
+            builder.returns(TypeName.get(info.getTargetType()));
+            builder.addParameter(ParameterSpec.builder(TypeName.get(info.getSourceType()), "source").build());
+            return builder;
+        }
+        return MethodSpec.overriding(method);
     }
 }

processor/src/main/java/com/devindi/mapper/MappingInfo.java

@@ -13,8 +13,8 @@ public class MappingInfo {
     private final TypeMirror sourceType;
     private final TypeMirror targetType;
     private final ExecutableElement method;
-    private final Name sourceName;
-    private final Name mappingName;
+    private final CharSequence sourceName;
+    private final CharSequence mappingName;
 
     public MappingInfo(ExecutableElement method) {
         targetType = method.getReturnType();
@@ -31,6 +31,14 @@ public MappingInfo(ExecutableElement method) {
         this.method = method;
     }
 
+    public MappingInfo(TypeMirror source, TypeMirror target) {
+        sourceType = source;
+        targetType = target;
+        this.sourceName = "source";
+        mappingName = "convert";
+        method = null;
+    }
+
     public TypeMirror getSourceType() {
         return sourceType;
     }
@@ -39,15 +47,34 @@ public TypeMirror getTargetType() {
         return targetType;
     }
 
-    public Name getSourceName() {
-        return sourceName;
+    public ExecutableElement getMethod() {
+        return method;
     }
 
-    public Name getMappingName() {
+    public CharSequence getMethodName() {
         return mappingName;
     }
 
-    public ExecutableElement getMethod() {
-        return method;
+    public CharSequence getSourceName() {
+        return sourceName;
+    }
+
+    public String getSourceFieldName(String defaultName) {
+        if (method == null) {
+            return defaultName;
+        }
+        com.devindi.mapper.Mapping annotation = method.getAnnotation(com.devindi.mapper.Mapping.class);
+        if (annotation != null && annotation.target().toLowerCase().equals(defaultName)) {
+            return annotation.source();
+        }
+        Mappings mappings = method.getAnnotation(Mappings.class);
+        if (mappings != null) {
+            for (com.devindi.mapper.Mapping fieldMapping : mappings.value()) {
+                if (fieldMapping != null && fieldMapping.target().toLowerCase().equals(defaultName)) {
+                    return fieldMapping.source();
+                }
+            }
+        }
+        return defaultName;
     }
 }

sample/src/main/java/com/example/nested/AutoDriverMapper.java

@@ -0,0 +1,10 @@
+package com.example.nested;
+
+import com.devindi.mapper.Mapper;
+import com.devindi.mapper.Mapping;
+
+@Mapper
+public interface AutoDriverMapper {
+    @Mapping(source = "license", target = "licenseDto")
+    DriverDto toDto(Driver d);
+}

sample/src/test/java/com/example/nested/DriverMapperTest.java

@@ -20,4 +20,17 @@ public void testNestedMapping() {
         assertNull(driverDto.getLicenseDto().getPhotoUrl());
         assertEquals(date, driverDto.getLicenseDto().getValidUntil());
     }
+
+    @Test
+    public void testAutoMapping() {
+        Date date = new Date();
+        Driver d = new Driver(25, "John Doe", new DriverLicense("42", null, date));
+        AutoDriverMapper driverMapper = new AutoDriverMapperImpl();
+        DriverDto driverDto = driverMapper.toDto(d);
+        assertEquals(25, driverDto.getAge());
+        assertEquals("John Doe", driverDto.getName());
+        assertEquals("42", driverDto.getLicenseDto().getId());
+        assertNull(driverDto.getLicenseDto().getPhotoUrl());
+        assertEquals(date, driverDto.getLicenseDto().getValidUntil());
+    }
 }