From a6c90e55156fdefa9d3444454ab55fc6a965229c Mon Sep 17 00:00:00 2001
From: Edouard DUPIN <yui.heero@gmail.com>
Date: Thu, 8 Jul 2021 14:18:29 +0200
Subject: [PATCH] [DEV] detect empty constructor (one)

---
 README.md                                     |  1 -
 .../builder/IntrospectionModelComplex.java    | 45 ++++++++++++++-----
 2 files changed, 35 insertions(+), 11 deletions(-)

diff --git a/README.md b/README.md
index 0f83f32..0ecb711 100644
--- a/README.md
+++ b/README.md
@@ -14,7 +14,6 @@ A POJO parse is in progress (based on SAX too)
 
 POJO need to implement (TODO list):
 
-  - Enumeration reader / writer
   - Immutable reader/writer
   - Record reader/writer
 
diff --git a/src/org/atriasoft/exml/builder/IntrospectionModelComplex.java b/src/org/atriasoft/exml/builder/IntrospectionModelComplex.java
index 1a669cb..ca4d123 100644
--- a/src/org/atriasoft/exml/builder/IntrospectionModelComplex.java
+++ b/src/org/atriasoft/exml/builder/IntrospectionModelComplex.java
@@ -36,6 +36,8 @@ public class IntrospectionModelComplex extends IntrospectionModel {
 	// TODO Optimize this with external object for basic types....
 	private final Method valueof; // used for the set Text if the object is an end point...
 	private final Method tostring; // used for the set Text if the object is an end point...
+	private final boolean isSubClass; // if true, the constructor must be called with a null first object. 
+	private final Constructor<?> constructorEmpty;
 	private final List<IntrospectionProperty> nodes = new ArrayList<>();
 	
 	private final List<IntrospectionProperty> attributes = new ArrayList<>();
@@ -53,6 +55,14 @@ public class IntrospectionModelComplex extends IntrospectionModel {
 	public IntrospectionModelComplex(final Class<?> classType) throws ExmlBuilderException {
 		super(classType);
 		try {
+			if (classType.getNestHost() == classType) {
+				this.isSubClass = false;
+			} else if (!Modifier.isStatic(classType.getModifiers())) {
+				this.isSubClass = true;
+			} else {
+				this.isSubClass = false;
+			}
+			
 			final Boolean isDefaultAttribute = getIsDefaultAttribute(classType, IntrospectionModel.DEFAULT_ATTRIBUTE);
 			final Boolean isDefaultManaged = getIsDefaultManaged(classType, IntrospectionModel.DEFAULT_MANAGED);
 			final Boolean isDefaultOptional = getIsDefaultOptional(classType, IntrospectionModel.DEFAULT_OPTIONAL);
@@ -60,9 +70,27 @@ public class IntrospectionModelComplex extends IntrospectionModel {
 			Log.verbose("Introspect class: '" + classType.getCanonicalName() + "'");
 			final Constructor<?>[] constructors = this.classType.getConstructors();
 			Log.verbose("    Constructors: (" + constructors.length + ")");
+			Constructor<?> emptyConstructorTmp = null;
 			for (final Constructor<?> elem : constructors) {
-				Log.verbose("        - " + elem.toGenericString());
+				// we does not manage private field
+				if (!Modifier.isPublic(elem.getModifiers())) {
+					continue;
+				}
+				if (this.isSubClass) {
+					if (elem.getParameterCount() == 1) {
+						emptyConstructorTmp = elem;
+						Log.verbose("      >>> " + elem.toGenericString());
+					} else {
+						Log.verbose("        - " + elem.toGenericString());
+					}
+				} else if (elem.getParameterCount() == 0) {
+					emptyConstructorTmp = elem;
+					Log.verbose("      >>> " + elem.toGenericString());
+				} else {
+					Log.verbose("        - " + elem.toGenericString());
+				}
 			}
+			this.constructorEmpty = emptyConstructorTmp;
 			final Field[] fields = this.classType.getFields();
 			Log.verbose("    Fields: (" + fields.length + ")");
 			for (final Field elem : fields) {
@@ -347,18 +375,15 @@ public class IntrospectionModelComplex extends IntrospectionModel {
 	@Override
 	public Object createObject(final Map<String, Object> properties, final Map<String, List<Object>> nodes) throws ExmlBuilderException {
 		Object tmp;
+		if (this.constructorEmpty == null) {
+			throw new ExmlBuilderException("No constructor accessible for class: " + this.classType.getCanonicalName());
+		}
 		try {
-			// pb here, can not create a primitive object with the correct elements... ==> must be generated with a siblist of elements
-			Constructor<?>[] constructors = this.classType.getConstructors();
-			//Log.critical("Modifiers : " + Modifier.toString(this.classType.getModifiers()) + " ==> " + this.classType.getNestHost());
-			if (this.classType.getNestHost() == this.classType) {
-				// if nest class is identical ==> native class declaration.
-				tmp = constructors[0].newInstance();
-			} else if (!Modifier.isStatic(this.classType.getModifiers())) {
+			if (this.isSubClass) {
 				Object tmp2 = null;
-				tmp = constructors[0].newInstance(tmp2);
+				tmp = this.constructorEmpty.newInstance(tmp2);
 			} else {
-				tmp = constructors[0].newInstance();
+				tmp = this.constructorEmpty.newInstance();
 			}
 		} catch (InstantiationException | IllegalAccessException | IllegalArgumentException | InvocationTargetException | SecurityException e) {
 			// TODO Auto-generated catch block