Add support for method based injection. (#66)

Author: norrisjeremy

inject-generator/src/main/java/io/avaje/inject/generator/BeanReader.java

@@ -45,6 +45,8 @@ class BeanReader {
 
   private final List<FieldReader> injectFields = new ArrayList<>();
 
+  private final List<MethodReader> injectMethods = new ArrayList<>();
+
   private final List<String> interfaceTypes = new ArrayList<>();
 
   private String addForType;
@@ -146,6 +148,10 @@ List<FieldReader> getInjectFields() {
     return injectFields;
   }
 
+  List<MethodReader> getInjectMethods() {
+    return injectMethods;
+  }
+
   void read(boolean factory) {
     for (Element element : beanType.getEnclosedElements()) {
       ElementKind kind = element.getKind();
@@ -169,6 +175,10 @@ void read(boolean factory) {
     for (FieldReader fields : injectFields) {
       fields.checkRequest(requestParams);
     }
+    for (MethodReader methods : injectMethods) {
+      methods.addImports(importTypes);
+      methods.checkRequest(requestParams);
+    }
     for (MethodReader factoryMethod : factoryMethods) {
       factoryMethod.addImports(importTypes);
     }
@@ -245,6 +255,15 @@ private void readMethod(Element element, boolean factory) {
       }
     }
 
+    Inject inject = element.getAnnotation(Inject.class);
+    if (inject != null) {
+      MethodReader methodReader = new MethodReader(context, methodElement, beanType);
+      methodReader.read();
+      if (!methodReader.getParams().isEmpty()) {
+        injectMethods.add(methodReader);
+      }
+    }
+
     if (context.isPostConstructAvailable()) {
       PostConstruct pcMarker = element.getAnnotation(PostConstruct.class);
       if (pcMarker != null) {
@@ -309,6 +328,10 @@ boolean isFieldInjectionRequired() {
     return !injectFields.isEmpty();
   }
 
+  boolean isMethodInjectionRequired() {
+    return !injectMethods.isEmpty();
+  }
+
   void buildAddFor(Append writer) {
     writer.append("    if (builder.isAddBeanFor(");
     if (addForType != null) {
@@ -413,6 +436,9 @@ void writeRequestCreate(Append writer) {
     for (FieldReader field : injectFields) {
       field.writeRequestDependency(writer);
     }
+    for (MethodReader method : injectMethods) {
+      method.writeRequestDependency(writer);
+    }
     requestParams.writeRequestCreate(writer);
     writer.resetNextName();
     writer.append("    %s bean = new %s(", shortName, shortName);
@@ -423,6 +449,11 @@ void writeRequestCreate(Append writer) {
     for (FieldReader field : injectFields) {
       field.writeRequestInject(writer);
     }
+    for (MethodReader method : injectMethods) {
+        writer.append("    bean.%s(", method.getName());
+        method.writeRequestConstructor(writer);
+        writer.append(");").eol();
+    }
     writer.append("    return bean;").eol();
     writer.append("  }").eol();
   }

inject-generator/src/main/java/io/avaje/inject/generator/MethodReader.java

@@ -125,7 +125,7 @@ String builderBuildBean() {
       if (i > 0) {
         sb.append(",");
       }
-      sb.append(params.get(i).builderGetDependency());
+      sb.append(params.get(i).builderGetDependency("builder"));
     }
     sb.append(");");
     return sb.toString();
@@ -268,13 +268,13 @@ static class MethodParam {
       this.genericType = GenericType.maybe(paramType);
     }
 
-    String builderGetDependency() {
+    String builderGetDependency(String builderName) {
       StringBuilder sb = new StringBuilder();
       if (genericType != null) {
         // passed as provider to build method
         sb.append("prov").append(providerIndex).append(".get(");
       } else {
-        sb.append("builder.").append(utilType.getMethod());
+        sb.append(builderName).append(".").append(utilType.getMethod());
       }
       if (genericType == null) {
         sb.append(Util.shortName(paramType)).append(".class");

inject-generator/src/main/java/io/avaje/inject/generator/SimpleBeanWriter.java

@@ -97,7 +97,13 @@ private void writeStaticFactoryMethod() {
         param.addProviderParam(writer, providerIndex++);
       }
     }
-
+    for (MethodReader methodReader : beanReader.getInjectMethods()) {
+      for (MethodReader.MethodParam param : methodReader.getParams()) {
+        if (param.isGenericType()) {
+          param.addProviderParam(writer, providerIndex++);
+        }
+      }
+    }
     writer.append(") {").eol();
 
     beanReader.buildAddFor(writer);
@@ -109,21 +115,32 @@ private void writeStaticFactoryMethod() {
       if (i > 0) {
         writer.append(",");
       }
-      writer.append(params.get(i).builderGetDependency());
+      writer.append(params.get(i).builderGetDependency("builder"));
     }
     writer.append(");").eol();
 
     beanReader.buildRegister(writer);
     if (beanReader.isLifecycleRequired()) {
       beanReader.buildAddLifecycle(writer);
     }
-    if (beanReader.isFieldInjectionRequired()) {
+    if (beanReader.isFieldInjectionRequired() || beanReader.isMethodInjectionRequired()) {
       writer.append("      builder.addInjector(b -> {").eol();
       for (FieldReader fieldReader : beanReader.getInjectFields()) {
         String fieldName = fieldReader.getFieldName();
         String getDependency = fieldReader.builderGetDependency();
         writer.append("        $bean.%s = %s;", fieldName, getDependency).eol();
       }
+      for (MethodReader methodReader : beanReader.getInjectMethods()) {
+        writer.append("        $bean.%s(", methodReader.getName());
+        List<MethodReader.MethodParam> methodParams = methodReader.getParams();
+        for (int i = 0; i < methodParams.size(); i++) {
+          if (i > 0) {
+            writer.append(",");
+          }
+          writer.append(methodParams.get(i).builderGetDependency("b"));
+        }
+        writer.append(");").eol();
+      }
       writer.append("      });").eol();
     }
     writer.append("    }").eol();

inject-test/src/test/java/org/example/coffee/fruit/AppleService.java

@@ -9,14 +9,17 @@ class AppleService {
   @Inject
   BananaService bananaService;
 
-  @Inject
   PeachService peachService;
 
+  @Inject
+  void setPeachService(PeachService peachService) {
+    this.peachService = peachService;
+  }
+
   String ban() {
     return bananaService.ban("hello");
   }
 
-
   void apple(String a, String b, String c) {
     System.out.println("apple> a: " + a + " b:" + b + " c:" + c);
     bananaService.banana(a, b, c);

inject-test/src/test/java/org/example/request/AController.java

@@ -12,9 +12,14 @@ public class AController {
   @Inject
   AService service;
 
-  @Inject
   Context context;
 
+  @Inject
+  AController withContext(Context context) {
+    this.context = context;
+    return this;
+  }
+
   public String get() {
     return "hi " + context.toString() + service.hi();
   }

inject-test/src/test/java/org/example/request/JexController.java

@@ -12,9 +12,14 @@ public class JexController {
   @Inject
   AService service;
 
-  @Inject
   Context context;
 
+  @Inject
+  JexController withContext(Context context) {
+    this.context = context;
+    return this;
+  }
+
   public String get() {
     return "hi " + context.toString() + service.hi();
   }