diff --git a/src/main/kotlin/io/openapiprocessor/core/converter/SchemaInfo.kt b/src/main/kotlin/io/openapiprocessor/core/converter/SchemaInfo.kt
index f23c845b..a6dcc699 100644
--- a/src/main/kotlin/io/openapiprocessor/core/converter/SchemaInfo.kt
+++ b/src/main/kotlin/io/openapiprocessor/core/converter/SchemaInfo.kt
@@ -203,13 +203,13 @@ class SchemaInfo(
     }
 
     /**
-     * iterate over items
+     * iterate over composed items
      */
     fun eachItemOf(action: (info: SchemaInfo) -> Unit) {
         schema?.getItems()?.forEachIndexed { index, schema ->
             action(SchemaInfo(
                 path = path,
-                name = "${name}-of-${index}",
+                name = "${name}_${itemOf()!!.capitalize()}_${index}",
                 schema = schema,
                 resolver = resolver
             ))
diff --git a/src/main/kotlin/io/openapiprocessor/core/model/Api.kt b/src/main/kotlin/io/openapiprocessor/core/model/Api.kt
index d2b87472..f1bad813 100644
--- a/src/main/kotlin/io/openapiprocessor/core/model/Api.kt
+++ b/src/main/kotlin/io/openapiprocessor/core/model/Api.kt
@@ -17,6 +17,7 @@
 package io.openapiprocessor.core.model
 
 import io.openapiprocessor.core.model.datatypes.DataType
+import io.openapiprocessor.core.model.datatypes.ModelDataType
 import io.openapiprocessor.core.model.datatypes.ObjectDataType
 import io.openapiprocessor.core.model.datatypes.StringEnumDataType
 import java.util.function.Consumer
@@ -60,6 +61,10 @@ class Api(
         models.getObjectDataTypes().forEach(action)
     }
 
+    fun forEachModelDataType(action: Consumer<ModelDataType>) {
+        models.getModelDataTypes().forEach(action)
+    }
+
     fun forEachEnumDataType(action: Consumer<StringEnumDataType>) {
         models.getEnumDataTypes().forEach(action)
     }
diff --git a/src/main/kotlin/io/openapiprocessor/core/model/DataTypes.kt b/src/main/kotlin/io/openapiprocessor/core/model/DataTypes.kt
index e6a8812c..55296a52 100644
--- a/src/main/kotlin/io/openapiprocessor/core/model/DataTypes.kt
+++ b/src/main/kotlin/io/openapiprocessor/core/model/DataTypes.kt
@@ -16,10 +16,7 @@
 
 package io.openapiprocessor.core.model
 
-import io.openapiprocessor.core.model.datatypes.DataType
-import io.openapiprocessor.core.model.datatypes.MappedDataType
-import io.openapiprocessor.core.model.datatypes.ObjectDataType
-import io.openapiprocessor.core.model.datatypes.StringEnumDataType
+import io.openapiprocessor.core.model.datatypes.*
 
 /**
  * Container of data types from OpenAPI '#/component/schemas'.
@@ -52,6 +49,21 @@ class DataTypes {
             .toList()
     }
 
+    /**
+     * provides the *object* data types (model classes) used by the api endpoints.
+     * For this objects the processor will create POJOs classes.
+     *
+     * experimental: will probably replace getObjectDataTypes().
+     *
+     * @return list of object data types
+     */
+    fun getModelDataTypes(): Collection<ModelDataType> {
+        return types.values
+            .filterIsInstance<ModelDataType>()
+            .filter { it.isModel() }
+            .toList()
+    }
+
     /**
      * provides the enum data types (model classes) used by the api endpoints.
      * For this objects the processor will create enum classes.
diff --git a/src/main/kotlin/io/openapiprocessor/core/model/datatypes/ComposedObjectDataType.kt b/src/main/kotlin/io/openapiprocessor/core/model/datatypes/ComposedObjectDataType.kt
index a92b0b44..fd023183 100644
--- a/src/main/kotlin/io/openapiprocessor/core/model/datatypes/ComposedObjectDataType.kt
+++ b/src/main/kotlin/io/openapiprocessor/core/model/datatypes/ComposedObjectDataType.kt
@@ -30,7 +30,7 @@ class ComposedObjectDataType(
     constraints: DataTypeConstraints? = null,
     deprecated: Boolean = false
 
-): DataTypeBase(constraints, deprecated) {
+): DataTypeBase(constraints, deprecated), ModelDataType {
 
     override fun getName(): String {
         return type
@@ -51,8 +51,27 @@ class ComposedObjectDataType(
             .toSet()
     }
 
+    // todo find better name
     override fun isComposed(): Boolean {
         return of != "allOf"
     }
 
+    override fun isModel(): Boolean {
+        return of == "allOf"
+    }
+
+    override fun getProperties(): Map<String, DataType> {
+        val properties = linkedMapOf<String, DataType>()
+
+        if (of == "allOf") {
+            items.forEach {
+                if (it is ObjectDataType) {
+                    properties.putAll(it.getProperties())
+                }
+            }
+        }
+
+        return properties
+    }
+
 }
diff --git a/src/main/kotlin/io/openapiprocessor/core/model/datatypes/ModelDataType.kt b/src/main/kotlin/io/openapiprocessor/core/model/datatypes/ModelDataType.kt
new file mode 100644
index 00000000..9dd4d5ab
--- /dev/null
+++ b/src/main/kotlin/io/openapiprocessor/core/model/datatypes/ModelDataType.kt
@@ -0,0 +1,14 @@
+/*
+ * Copyright © 2020 https://github.com/openapi-processor/openapi-processor-core
+ * PDX-License-Identifier: Apache-2.0
+ */
+
+package io.openapiprocessor.core.model.datatypes
+
+interface ModelDataType: DataType {
+
+    fun isModel(): Boolean
+
+    fun getProperties(): Map<String, DataType>
+
+}
diff --git a/src/main/kotlin/io/openapiprocessor/core/model/datatypes/ObjectDataType.kt b/src/main/kotlin/io/openapiprocessor/core/model/datatypes/ObjectDataType.kt
index 4bf0a6b0..15dc615e 100644
--- a/src/main/kotlin/io/openapiprocessor/core/model/datatypes/ObjectDataType.kt
+++ b/src/main/kotlin/io/openapiprocessor/core/model/datatypes/ObjectDataType.kt
@@ -30,7 +30,7 @@ class ObjectDataType(
     constraints: DataTypeConstraints? = null,
     deprecated: Boolean = false
 
-): DataTypeBase(constraints, deprecated) {
+): DataTypeBase(constraints, deprecated), ModelDataType {
 
     override fun getName(): String {
         return type
@@ -55,7 +55,16 @@ class ObjectDataType(
         return properties[name]!!
     }
 
+    @Deprecated("do not override groovys getProperties()", ReplaceWith("getProperties()"))
     fun getObjectProperties(): Map<String, DataType> {
+        return getProperties()
+    }
+
+    override fun isModel(): Boolean {
+        return true
+    }
+
+    override fun getProperties(): Map<String, DataType> {
         return properties
     }
 
diff --git a/src/main/kotlin/io/openapiprocessor/core/writer/java/ApiWriter.kt b/src/main/kotlin/io/openapiprocessor/core/writer/java/ApiWriter.kt
index 1a4a775a..51ae82fa 100644
--- a/src/main/kotlin/io/openapiprocessor/core/writer/java/ApiWriter.kt
+++ b/src/main/kotlin/io/openapiprocessor/core/writer/java/ApiWriter.kt
@@ -21,9 +21,9 @@ import com.google.googlejavaformat.java.JavaFormatterOptions
 import io.openapiprocessor.core.converter.ApiOptions
 import io.openapiprocessor.core.model.Api
 import io.openapiprocessor.core.model.Interface
-import io.openapiprocessor.core.model.datatypes.ObjectDataType
 import io.openapiprocessor.core.model.datatypes.StringEnumDataType
 import io.openapiprocessor.core.misc.toURL
+import io.openapiprocessor.core.model.datatypes.ModelDataType
 import java.io.BufferedWriter
 import java.io.StringWriter
 import java.io.Writer
@@ -73,7 +73,7 @@ class ApiWriter(
     }
 
     private fun writeObjectDataTypes(api: Api) {
-        api.forEachObjectDataType {
+        api.forEachModelDataType {
             val target = modelFolder.resolve ("${it.getName()}.java")
             val writer = BufferedWriter(PathWriter(target))
             writeDataType(writer, it)
@@ -96,7 +96,7 @@ class ApiWriter(
         writer.write(format(raw.toString()))
     }
 
-    private fun writeDataType(writer: Writer, dataType: ObjectDataType) {
+    private fun writeDataType(writer: Writer, dataType: ModelDataType) {
         val raw = StringWriter()
         dataTypeWriter.write(raw, dataType)
         writer.write(format(raw.toString ()))
diff --git a/src/main/kotlin/io/openapiprocessor/core/writer/java/DataTypeWriter.kt b/src/main/kotlin/io/openapiprocessor/core/writer/java/DataTypeWriter.kt
index 72f36d45..eae6e872 100644
--- a/src/main/kotlin/io/openapiprocessor/core/writer/java/DataTypeWriter.kt
+++ b/src/main/kotlin/io/openapiprocessor/core/writer/java/DataTypeWriter.kt
@@ -18,7 +18,7 @@ package io.openapiprocessor.core.writer.java
 
 import io.openapiprocessor.core.converter.ApiOptions
 import io.openapiprocessor.core.model.datatypes.DataType
-import io.openapiprocessor.core.model.datatypes.ObjectDataType
+import io.openapiprocessor.core.model.datatypes.ModelDataType
 import java.io.Writer
 
 /**
@@ -33,7 +33,7 @@ class DataTypeWriter(
     private val validationAnnotations: BeanValidationFactory = BeanValidationFactory()
 ) {
 
-    fun write(target: Writer, dataType: ObjectDataType) {
+    fun write(target: Writer, dataType: ModelDataType) {
         headerWriter.write(target)
         target.write("package ${dataType.getPackageName()};\n\n")
 
@@ -52,16 +52,14 @@ class DataTypeWriter(
 
         target.write("public class ${dataType.getName()} {\n\n")
 
-        val propertyNames = dataType.getObjectProperties().keys
-        propertyNames.forEach {
-            val javaPropertyName = toCamelCase(it)
-            val propDataType = dataType.getObjectProperty(it)
-            target.write(getProp(it, javaPropertyName, propDataType))
+        val properties = dataType.getProperties()
+        properties.forEach { (propName, propDataType) ->
+            val javaPropertyName = toCamelCase(propName)
+            target.write(getProp(propName, javaPropertyName, propDataType))
         }
 
-        propertyNames.forEach {
-            val javaPropertyName = toCamelCase(it)
-            val propDataType = dataType.getObjectProperty(it)
+        properties.forEach { (propName, propDataType) ->
+            val javaPropertyName = toCamelCase(propName)
             target.write(getGetter(javaPropertyName, propDataType))
             target.write(getSetter(javaPropertyName, propDataType))
         }
@@ -122,14 +120,14 @@ class DataTypeWriter(
         return result
     }
 
-    private fun collectImports(packageName: String, dataType: ObjectDataType): List<String> {
+    private fun collectImports(packageName: String, dataType: ModelDataType): List<String> {
         val imports = mutableSetOf<String>()
         imports.add("com.fasterxml.jackson.annotation.JsonProperty")
 
         imports.addAll(dataType.getReferencedImports())
 
         if (apiOptions.beanValidation) {
-            dataType.getObjectProperties().values.forEach {
+            dataType.getProperties().values.forEach {
                 imports.addAll(validationAnnotations.collectImports(it))
             }
         }
diff --git a/src/test/kotlin/io/openapiprocessor/core/model/datatypes/ComposedObjectDataTypeSpec.kt b/src/test/kotlin/io/openapiprocessor/core/model/datatypes/ComposedObjectDataTypeSpec.kt
new file mode 100644
index 00000000..b5448e72
--- /dev/null
+++ b/src/test/kotlin/io/openapiprocessor/core/model/datatypes/ComposedObjectDataTypeSpec.kt
@@ -0,0 +1,30 @@
+/*
+ * Copyright © 2020 https://github.com/openapi-processor/openapi-processor-core
+ * PDX-License-Identifier: Apache-2.0
+ */
+
+package io.openapiprocessor.core.model.datatypes
+
+import io.kotest.core.spec.style.StringSpec
+import io.kotest.matchers.shouldBe
+
+class ComposedObjectDataTypeSpec : StringSpec({
+
+    "loop properties of allOf objects as if it was a single object" {
+        val composed = ComposedObjectDataType("Foo", "pkg", "allOf", listOf(
+            ObjectDataType("Foo", "pkg", linkedMapOf(
+                Pair("foo", StringDataType()),
+                Pair("foobar", StringDataType())
+            )),
+            ObjectDataType("Bar", "pkg", linkedMapOf(
+                Pair("bar", StringDataType()),
+                Pair("barfoo", StringDataType())
+            ))
+        ))
+
+        val properties = composed.getProperties()
+
+        properties.keys shouldBe linkedSetOf("foo", "foobar", "bar", "barfoo")
+    }
+
+})
diff --git a/src/test/kotlin/io/openapiprocessor/core/writer/java/ApiWriterSpec.kt b/src/test/kotlin/io/openapiprocessor/core/writer/java/ApiWriterSpec.kt
index 5cf9a10e..accbd4b8 100644
--- a/src/test/kotlin/io/openapiprocessor/core/writer/java/ApiWriterSpec.kt
+++ b/src/test/kotlin/io/openapiprocessor/core/writer/java/ApiWriterSpec.kt
@@ -218,7 +218,7 @@ class ApiWriterSpec: StringSpec({
     "re-formats model sources" {
         val dtWriter = io.mockk.mockk<DataTypeWriter>()
         every { dtWriter.write(any(), any()) } answers {
-            arg<Writer>(0).write("  class \n  ${arg<ObjectDataType>(1).getName()} {   }\n")
+            arg<Writer>(0).write("  class \n  ${arg<ModelDataType>(1).getName()} {   }\n")
         }
 
         val dt = DataTypes()
diff --git a/src/testInt/groovy/com/github/hauner/openapi/processor/core/ProcessorEndToEndTest.groovy b/src/testInt/groovy/com/github/hauner/openapi/processor/core/ProcessorEndToEndTest.groovy
index eac15690..89233b69 100644
--- a/src/testInt/groovy/com/github/hauner/openapi/processor/core/ProcessorEndToEndTest.groovy
+++ b/src/testInt/groovy/com/github/hauner/openapi/processor/core/ProcessorEndToEndTest.groovy
@@ -37,7 +37,8 @@ class ProcessorEndToEndTest extends ProcessorTestBase {
         'ref-loop-array',
         'ref-parameter',
         'ref-parameter-with-primitive-mapping',
-        'response-content-multiple-no-content'
+        'response-content-multiple-no-content',
+        'schema-composed-allof'
     ]
 
     @Parameterized.Parameters(name = "{0}")
diff --git a/src/testInt/groovy/com/github/hauner/openapi/processor/core/ProcessorPendingTest.groovy b/src/testInt/groovy/com/github/hauner/openapi/processor/core/ProcessorPendingTest.groovy
index 8da54ce2..1bf09804 100644
--- a/src/testInt/groovy/com/github/hauner/openapi/processor/core/ProcessorPendingTest.groovy
+++ b/src/testInt/groovy/com/github/hauner/openapi/processor/core/ProcessorPendingTest.groovy
@@ -32,8 +32,8 @@ class ProcessorPendingTest extends ProcessorTestBase {
     @Parameterized.Parameters(name = "{0}")
     static Collection<TestSet> sources () {
         return [
-            new TestSet(name: 'ref-loop-array', processor: new TestProcessor(), parser: ParserType.SWAGGER),
-            new TestSet(name: 'ref-loop-array', processor: new TestProcessor(), parser: ParserType.OPENAPI4J)
+            new TestSet(name: 'schema-composed-allof', processor: new TestProcessor(), parser: ParserType.SWAGGER),
+            new TestSet(name: 'schema-composed-allof', processor: new TestProcessor(), parser: ParserType.OPENAPI4J)
         ]
     }
 
diff --git a/src/testInt/resources/tests/schema-composed-allof/generated.yaml b/src/testInt/resources/tests/schema-composed-allof/generated.yaml
new file mode 100644
index 00000000..496f414f
--- /dev/null
+++ b/src/testInt/resources/tests/schema-composed-allof/generated.yaml
@@ -0,0 +1,5 @@
+items:
+  - generated/api/Api.java
+  - generated/model/QueryResponse200.java
+  - generated/model/QueryResponse200_AllOf_0.java
+  - generated/model/QueryResponse200_AllOf_1.java
diff --git a/src/testInt/resources/tests/schema-composed-allof/generated/api/Api.java b/src/testInt/resources/tests/schema-composed-allof/generated/api/Api.java
new file mode 100644
index 00000000..a794c316
--- /dev/null
+++ b/src/testInt/resources/tests/schema-composed-allof/generated/api/Api.java
@@ -0,0 +1,16 @@
+/*
+ * This class is auto generated by https://github.com/hauner/openapi-processor-core.
+ * TEST ONLY.
+ */
+
+package generated.api;
+
+import annotation.Mapping;
+import generated.model.QueryResponse200;
+
+public interface Api {
+
+    @Mapping("/query")
+    QueryResponse200 getQuery();
+
+}
diff --git a/src/testInt/resources/tests/schema-composed-allof/generated/model/QueryResponse200.java b/src/testInt/resources/tests/schema-composed-allof/generated/model/QueryResponse200.java
new file mode 100644
index 00000000..8d953f20
--- /dev/null
+++ b/src/testInt/resources/tests/schema-composed-allof/generated/model/QueryResponse200.java
@@ -0,0 +1,34 @@
+/*
+ * This class is auto generated by https://github.com/hauner/openapi-processor-core.
+ * TEST ONLY.
+ */
+
+package generated.model;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+
+public class QueryResponse200 {
+
+    @JsonProperty("prop1")
+    private String prop1;
+
+    @JsonProperty("prop2")
+    private String prop2;
+
+    public String getProp1() {
+        return prop1;
+    }
+
+    public void setProp1(String prop1) {
+        this.prop1 = prop1;
+    }
+
+    public String getProp2() {
+        return prop2;
+    }
+
+    public void setProp2(String prop2) {
+        this.prop2 = prop2;
+    }
+
+}
diff --git a/src/testInt/resources/tests/schema-composed-allof/generated/model/QueryResponse200_AllOf_0.java b/src/testInt/resources/tests/schema-composed-allof/generated/model/QueryResponse200_AllOf_0.java
new file mode 100644
index 00000000..cc12225f
--- /dev/null
+++ b/src/testInt/resources/tests/schema-composed-allof/generated/model/QueryResponse200_AllOf_0.java
@@ -0,0 +1,23 @@
+/*
+ * This class is auto generated by https://github.com/hauner/openapi-processor-core.
+ * TEST ONLY.
+ */
+
+package generated.model;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+
+public class QueryResponse200_AllOf_0 {
+
+    @JsonProperty("prop1")
+    private String prop1;
+
+    public String getProp1() {
+        return prop1;
+    }
+
+    public void setProp1(String prop1) {
+        this.prop1 = prop1;
+    }
+
+}
diff --git a/src/testInt/resources/tests/schema-composed-allof/generated/model/QueryResponse200_AllOf_1.java b/src/testInt/resources/tests/schema-composed-allof/generated/model/QueryResponse200_AllOf_1.java
new file mode 100644
index 00000000..7096aa76
--- /dev/null
+++ b/src/testInt/resources/tests/schema-composed-allof/generated/model/QueryResponse200_AllOf_1.java
@@ -0,0 +1,23 @@
+/*
+ * This class is auto generated by https://github.com/hauner/openapi-processor-core.
+ * TEST ONLY.
+ */
+
+package generated.model;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+
+public class QueryResponse200_AllOf_1 {
+
+    @JsonProperty("prop2")
+    private String prop2;
+
+    public String getProp2() {
+        return prop2;
+    }
+
+    public void setProp2(String prop2) {
+        this.prop2 = prop2;
+    }
+
+}
diff --git a/src/testInt/resources/tests/schema-composed-allof/inputs.yaml b/src/testInt/resources/tests/schema-composed-allof/inputs.yaml
new file mode 100644
index 00000000..a7b02dbc
--- /dev/null
+++ b/src/testInt/resources/tests/schema-composed-allof/inputs.yaml
@@ -0,0 +1,2 @@
+items:
+  - inputs/openapi.yaml
diff --git a/src/testInt/resources/tests/schema-composed-allof/inputs/openapi.yaml b/src/testInt/resources/tests/schema-composed-allof/inputs/openapi.yaml
new file mode 100644
index 00000000..2b53c2a4
--- /dev/null
+++ b/src/testInt/resources/tests/schema-composed-allof/inputs/openapi.yaml
@@ -0,0 +1,23 @@
+openapi: 3.0.2
+info:
+  title: merge allOf into same object
+  version: 1.0.0
+
+paths:
+  /query:
+    get:
+      responses:
+        '200':
+          description: create result from allOff object
+          content:
+            application/json:
+              schema:
+                allOf:
+                  - type: object
+                    properties:
+                      prop1:
+                        type: string
+                  - type: object
+                    properties:
+                      prop2:
+                        type: string
diff --git a/src/testInt/resources/tests/schema-composed/generated.yaml b/src/testInt/resources/tests/schema-composed/generated.yaml
index 2a29e5e0..a76defcb 100644
--- a/src/testInt/resources/tests/schema-composed/generated.yaml
+++ b/src/testInt/resources/tests/schema-composed/generated.yaml
@@ -3,3 +3,4 @@ items:
   - generated/model/One.java
   - generated/model/Two.java
   - generated/model/Three.java
+  - generated/model/FooAllOf.java
diff --git a/src/testInt/resources/tests/schema-composed/generated/model/FooAllOf.java b/src/testInt/resources/tests/schema-composed/generated/model/FooAllOf.java
new file mode 100644
index 00000000..2ab83784
--- /dev/null
+++ b/src/testInt/resources/tests/schema-composed/generated/model/FooAllOf.java
@@ -0,0 +1,45 @@
+/*
+ * This class is auto generated by https://github.com/hauner/openapi-processor-core.
+ * TEST ONLY.
+ */
+
+package generated.model;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+
+public class FooAllOf {
+
+    @JsonProperty("one")
+    private String one;
+
+    @JsonProperty("two")
+    private String two;
+
+    @JsonProperty("three")
+    private String three;
+
+    public String getOne() {
+        return one;
+    }
+
+    public void setOne(String one) {
+        this.one = one;
+    }
+
+    public String getTwo() {
+        return two;
+    }
+
+    public void setTwo(String two) {
+        this.two = two;
+    }
+
+    public String getThree() {
+        return three;
+    }
+
+    public void setThree(String three) {
+        this.three = three;
+    }
+
+}