fix proxy generation with final methods (#896)

Fixes issue where we would try to generate proxies for classes with final methods

Author: SentryMan

blackbox-test-inject/src/main/java/org/example/myapp/lazy/LazyBean.java

@@ -27,4 +27,6 @@ void init(BeanScope scope) {
  void something() {}
 
  public void other() {}
+
+ protected void other2() {}
 }

blackbox-test-inject/src/main/java/org/example/myapp/lazy/RandomFactory.java

@@ -0,0 +1,18 @@
+package org.example.myapp.lazy;
+
+import java.security.SecureRandom;
+import java.util.Random;
+
+import io.avaje.inject.Bean;
+import io.avaje.inject.Factory;
+import io.avaje.inject.Lazy;
+import io.avaje.inject.Lazy.Kind;
+
+@Lazy(Kind.PROVIDER)
+@Factory
+public class RandomFactory {
+ @Bean
+ public Random secureRandom() {
+ return new SecureRandom();
+ }
+}

blackbox-test-inject/src/main/java/org/example/myapp/lazy2/package-info.java

@@ -1,9 +1,11 @@
 /**
  * Use Lazy for all the beans in this package.
- * <p>
- * Use {@code enforceProxy = true} to fail compilation if there is no default constructor/lazy not supported.
+ *
+ * <p>Use {@code enforceProxy = true} to fail compilation if there is no default constructor/lazy
+ * not supported.
  */
-@Lazy(enforceProxy = true)
+@Lazy(Kind.FORCE_PROXY)
 package org.example.myapp.lazy2;
 
 import io.avaje.inject.Lazy;
+import io.avaje.inject.Lazy.Kind;

blackbox-test-inject/src/test/java/org/example/myapp/beantypes/BeanTypeComponentTest.java

@@ -7,8 +7,6 @@
 
 import io.avaje.inject.BeanScope;
 
-import java.io.Serializable;
-
 class BeanTypesTest {
 
  @Test
@@ -18,7 +16,6 @@ void testBeanTypesRestrictingInjection() {
  assertFalse(scope.contains(BeanTypeComponent.class));
  assertThat(scope.get(AbstractSuperClass.class)).isNotNull();
  assertThat(scope.get(LimitedInterface.class)).isNotNull();
- assertThat(scope.get(Serializable.class)).isEqualTo("IAmSerializable");
  assertThat(scope.get(CharSequence.class)).isEqualTo("IAmNullable");
  }
  }

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

@@ -103,10 +103,13 @@ final class BeanReader {
  this.observerMethods = typeReader.observerMethods();
  this.importedComponent = importedComponent && constructor != null && constructor.isPublic();
  this.delayed = shouldDelay();
- this.lazyProxyType = !lazy || delayed ? null : Util.lazyProxy(actualType);
+ String lazyKind = Optional.ofNullable(lazyPrism).map(LazyPrism::value).orElse("");
+ boolean useProxy = !"PROVIDER".equals(lazyKind);
+ this.lazyProxyType = !lazy || !useProxy ? null : Util.lazyProxy(actualType);
  this.proxyLazy = lazy && lazyProxyType != null;
- if (lazy && !proxyLazy) {
- if (lazyPrism != null && lazyPrism.enforceProxy()) {
+
+ if (lazy && !proxyLazy && useProxy) {
+ if ("FORCE_PROXY".equals(lazyKind)) {
  logError(beanType, "Lazy beans must have an additional no-arg constructor");
  } else {
  logWarn(beanType, "Lazy beans should have an additional no-arg constructor");

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

@@ -10,6 +10,7 @@
 import java.util.Collections;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.Set;
 import java.util.function.Supplier;
 
@@ -75,10 +76,14 @@ final class MethodReader {
  var lazyPrism = Util.isLazy(element);
  lazy = lazyPrism != null;
  conditions.readAll(element);
- this.lazyProxyType = lazy ? Util.lazyProxy(element) : null;
+
+ String lazyKind = Optional.ofNullable(lazyPrism).map(LazyPrism::value).orElse("");
+ boolean useProxy = !"PROVIDER".equals(lazyKind);
+ this.lazyProxyType = !lazy || !useProxy ? null : Util.lazyProxy(element);
  this.proxyLazy = lazy && lazyProxyType != null;
- if (lazy && !proxyLazy) {
- if (lazyPrism.enforceProxy()) {
+
+ if (lazy && !proxyLazy && useProxy) {
+ if ("FORCE_PROXY".equals(lazyKind)) {
  logError(element, "Lazy return type must be abstract or have a no-arg constructor");
  } else {
  logWarn(element, "Lazy return type should be abstract or have a no-arg constructor");

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

@@ -163,19 +163,24 @@ private String methods() {
  }
 
  sb.append(" {\n ");
- if (!"void".equals(returnType.full())) {
- sb.append("return ");
- }
+ if (modifiers.contains(Modifier.PROTECTED)) {
+ sb.append("// @Lazy proxy does not support protected methods, instead use @Lazy(useProxy = false)");
+ sb.append("\n throw new UnsupportedOperationException();\n");
+ } else {
+ if (!"void".equals(returnType.full())) {
+ sb.append("return ");
+ }
 
- sb.append("onceProvider.get().").append(methodName);
- sb.append("(");
- for (int i = 0; i < parameters.size(); i++) {
- sb.append(parameters.get(i).getSimpleName().toString());
- if (i < parameters.size() - 1) {
- sb.append(", ");
+ sb.append("onceProvider.get().").append(methodName);
+ sb.append("(");
+ for (int i = 0; i < parameters.size(); i++) {
+ sb.append(parameters.get(i).getSimpleName().toString());
+ if (i < parameters.size() - 1) {
+ sb.append(", ");
+ }
  }
+ sb.append(");\n");
  }
- sb.append(");\n");
  sb.append(" }\n\n");
  }
  return sb.toString();

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

@@ -400,9 +400,10 @@ static TypeElement lazyProxy(Element element) {
  element instanceof TypeElement
  ? (TypeElement) element
  : APContext.asTypeElement(((ExecutableElement) element).getReturnType());
-
+ var notInterface = !type.getKind().isInterface();
  if (type.getModifiers().contains(Modifier.FINAL)
- || !type.getKind().isInterface() && !Util.hasNoArgConstructor(type)) {
+ || notInterface && !Util.hasNoArgConstructor(type)
+ || notInterface && Util.hasFinalMethods(type)) {
 
  return BeanTypesPrism.getOptionalOn(element)
  .map(BeanTypesPrism::value)
@@ -417,6 +418,14 @@ static TypeElement lazyProxy(Element element) {
  return type;
  }
 
+ private static boolean hasFinalMethods(TypeElement type) {
+ return ElementFilter.methodsIn(type.getEnclosedElements()).stream()
+ .filter(x -> !x.getModifiers().contains(Modifier.STATIC))
+ .filter(x -> !x.getModifiers().contains(Modifier.PRIVATE))
+ .filter(x -> !x.getModifiers().contains(Modifier.PROTECTED))
+ .anyMatch(m -> m.getModifiers().contains(Modifier.FINAL));
+ }
+
  static boolean hasNoArgConstructor(TypeElement beanType) {
  return ElementFilter.constructorsIn(beanType.getEnclosedElements()).stream()
  .anyMatch(e -> e.getParameters().isEmpty() && !e.getModifiers().contains(Modifier.PRIVATE));

inject-generator/src/test/java/io/avaje/inject/generator/models/valid/lazy/RandomFactory.java

@@ -0,0 +1,16 @@
+package io.avaje.inject.generator.models.valid.lazy;
+
+import java.security.SecureRandom;
+
+import io.avaje.inject.Bean;
+import io.avaje.inject.Factory;
+import io.avaje.inject.Lazy;
+
+@Lazy
+@Factory
+public class RandomFactory {
+ @Bean
+ public SecureRandom secureRandom() {
+ return new SecureRandom();
+ }
+}

inject/src/main/java/io/avaje/inject/Lazy.java

@@ -17,10 +17,32 @@
 @Retention(RetentionPolicy.SOURCE)
 @Target({ElementType.METHOD, ElementType.TYPE, ElementType.PACKAGE, ElementType.MODULE})
 public @interface Lazy {
+ /** Determine the kind of lazy initialization. */
+ Kind value() default Kind.AUTO_PROXY;
 
  /**
- * Ensures that a compile-time proxy is generated, will fail compilation if missing conditions for
- * generation
+ * Control whether a compile-time proxy is generated to support lazy initialization.
+ *
+ * <p>When using {@link Kind#FORCE_PROXY} a compile-time error will occur if the conditions for
+ * generating a proxy are not met (for example the class is final or has no no-args constructor).
+ * When using {@link Kind#AUTO_PROXY} a warning will be issued and lazy initialization will fall
+ * back to provider based lazy initialization.
+ *
+ * <p>When using {@link Kind#PROVIDER} no proxy is generated and lazy initialization is done via a
+ * provider.
  */
- boolean enforceProxy() default false;
+ enum Kind {
+ /**
+ * Ensures that a compile-time proxy is generated, will fail compilation if missing conditions
+ * for generation
+ */
+ FORCE_PROXY,
+ /**
+ * Attempt compile-time proxy, will warn and fallback to provider compilation if missing
+ * conditions for generation
+ */
+ AUTO_PROXY,
+ /** No proxy, use a provider based lazy initialization */
+ PROVIDER
+ }
 }