#365 inject default implementation, add documentation for default behavior

processor/src/main/java/org/mapstruct/ap/services/DefaultAccessorNamingStrategy.java

@@ -29,6 +29,10 @@ import org.mapstruct.spi.AccessorNamingStrategy;
  */
 class DefaultAccessorNamingStrategy implements AccessorNamingStrategy {
 
+    @Override
+    public void setDefaultAccessorNamingStrategy(AccessorNamingStrategy defaultAccessorNamingStrategy) {
+    }
+
     @Override
     public boolean isNonBooleanGetterName(String methodName) {
         return methodName.startsWith( "get" ) && methodName.length() > 3;

processor/src/main/java/org/mapstruct/ap/services/Services.java

@@ -48,10 +48,12 @@ public class Services {
     }
 
     private static AccessorNamingStrategy findAccessorNamingStrategy() {
+        AccessorNamingStrategy defaultImpl = new DefaultAccessorNamingStrategy();
         AccessorNamingStrategy impl = find( AccessorNamingStrategy.class );
         if ( impl == null ) {
-            impl = new DefaultAccessorNamingStrategy();
+            impl = defaultImpl;
         }
+        impl.setDefaultAccessorNamingStrategy( defaultImpl );
         return impl;
     }
 

spi/src/main/java/org/mapstruct/spi/AccessorNamingStrategy.java

@@ -25,8 +25,20 @@ package org.mapstruct.spi;
  */
 public interface AccessorNamingStrategy {
 
+    /**
+     * Set the default {@link AccessorNamingStrategy} implementation. Custom implementations may use it to
+     * keep parts of the default behavior. This method is invoked before any other method of the interface.
+     * <p>
+     * Default implementation: Does nothing.
+     *
+     * @param defaultAccessorNamingStrategy The default implementation.
+     */
+    void setDefaultAccessorNamingStrategy(AccessorNamingStrategy defaultAccessorNamingStrategy);
+
     /**
      * Determine if a method name defines a getter with a non-boolean return type.
+     * <p>
+     * Default implementation: Method name starts with "get" and is longer than 3 characters.
      *
      * @param methodName The method name.
      * @return {@code true} if the method name can be a non-boolean getter, {@code false} otherwise.
@@ -35,6 +47,8 @@ public interface AccessorNamingStrategy {
 
     /**
      * Determine if a method name defines a getter with a boolean return type.
+     * <p>
+     * Default implementation: Method name starts with "is" and is longer than 2 characters.
      *
      * @param methodName The method name.
      * @return {@code true} if the method name can be a boolean getter, {@code false} otherwise.
@@ -43,6 +57,8 @@ public interface AccessorNamingStrategy {
 
     /**
      * Determine if a method name defines a setter.
+     * <p>
+     * Default implementation: Method name starts with "set" and is longer than 3 characters.
      *
      * @param methodName The method name.
      * @return {@code true} if the method name can be a setter, {@code false} otherwise.
@@ -51,6 +67,8 @@ public interface AccessorNamingStrategy {
 
     /**
      * Determine if a method name defines an adder.
+     * <p>
+     * Default implementation: Method name starts with "add" and is longer than 3 characters.
      *
      * @param methodName The method name.
      * @return {@code true} if the method name can be an adder, {@code false} otherwise.
@@ -60,6 +78,9 @@ public interface AccessorNamingStrategy {
     /**
      * Extract the property name from a method name for which {@link #isNonBooleanGetterName(String)} returned
      * {@code true}.
+     * <p>
+     * Default implementation: Remove first 3 characters ("get") of the method name, and
+     * {@link java.beans.Introspector#decapitalize(String) decapitalize} the result.
      *
      * @param methodName The method name, guaranteed to be a non-boolean getter name.
      * @return The property name corresponding to the method name.
@@ -69,6 +90,9 @@ public interface AccessorNamingStrategy {
     /**
      * Extract the property name from a method name for which {@link #isBooleanGetterName(String)} returned
      * {@code true}.
+     * <p>
+     * Default implementation: Remove the first 2 characters ("is") of the method name, and
+     * {@link java.beans.Introspector#decapitalize(String) decapitalize} the result.
      *
      * @param methodName The method name, guaranteed to be a boolean getter name.
      * @return The property name corresponding to the method name.
@@ -77,6 +101,9 @@ public interface AccessorNamingStrategy {
 
     /**
      * Extract the property name from a method name for which {@link #isSetterName(String)} returned {@code true}.
+     * <p>
+     * Default implementation: Remove the first 3 characters ("set") of the method name, and
+     * {@link java.beans.Introspector#decapitalize(String) decapitalize} the result.
      *
      * @param methodName The method name, guaranteed to be a setter name.
      * @return The property name corresponding to the method name.
@@ -86,6 +113,9 @@ public interface AccessorNamingStrategy {
     /**
      * Extract the element name (singular form of the collection's property name) from a method name for which
      * {@link #isAdderName(String)} returned {@code true}.
+     * <p>
+     * Default implementation: Remove the first 3 characters ("add") of the method name, and
+     * {@link java.beans.Introspector#decapitalize(String) decapitalize} the result.
      *
      * @param methodName The method name, guaranteed to be an adder name.
      * @return The element name corresponding to the method name.
@@ -94,6 +124,8 @@ public interface AccessorNamingStrategy {
 
     /**
      * Extract the non-boolean getter method name from the setter method name of the same property.
+     * <p>
+     * Default implementation: Replace the first 3 characters ("get") of the method name with "set".
      *
      * @param methodName The method name, guaranteed to be a setter name.
      * @return The corresponding non-boolean getter method name.