diff --git a/src/main/java/eu/hbp/mip/models/DTOs/Exareme2AlgorithmRequestDTO.java b/src/main/java/eu/hbp/mip/models/DTOs/Exareme2AlgorithmRequestDTO.java
index 7df8a3cc516fa1f00102875497b7778dc0de93d9..5562df1398aaa199617e82d5d0a9e761d67f8b34 100644
--- a/src/main/java/eu/hbp/mip/models/DTOs/Exareme2AlgorithmRequestDTO.java
+++ b/src/main/java/eu/hbp/mip/models/DTOs/Exareme2AlgorithmRequestDTO.java
@@ -19,7 +19,7 @@ public class Exareme2AlgorithmRequestDTO {
     @SerializedName("preprocessing")
     private HashMap<String, Object> preprocessing;
 
-    public Exareme2AlgorithmRequestDTO(UUID experimentUUID, List<ExaremeAlgorithmRequestParamDTO> exaremeAlgorithmRequestParamDTOs, List<ExaremeAlgorithmDTO.Transformer> exaremeTransformers) {
+    public Exareme2AlgorithmRequestDTO(UUID experimentUUID, List<ExaremeAlgorithmRequestParamDTO> exaremeAlgorithmRequestParamDTOs, List<ExaremeAlgorithmDTO.ExaremeTransformerDTO> exaremeTransformers) {
         this.request_id = experimentUUID.toString();
         Exareme2AlgorithmRequestDTO.InputData inputData = new Exareme2AlgorithmRequestDTO.InputData();
         HashMap<String, Object> exareme2Parameters = new HashMap<>();
@@ -51,7 +51,7 @@ public class Exareme2AlgorithmRequestDTO {
                     exareme2Parameters.put(parameter.getName(), convertStringToMultipleValues(parameter.getValue()));
             }
         });
-        if (exaremeTransformers.size() > 0) {
+        if (exaremeTransformers != null) {
             exaremeTransformers.forEach(transformer -> {
                 HashMap<String, Object> transformerParameterDTOs = new HashMap<>();
                 for (ExaremeAlgorithmRequestParamDTO parameter : transformer.getParameters()) {
diff --git a/src/main/java/eu/hbp/mip/models/DTOs/ExaremeAlgorithmDTO.java b/src/main/java/eu/hbp/mip/models/DTOs/ExaremeAlgorithmDTO.java
index 16d68771a4c305b5334a40f12a5e5dbbd5b56b36..be3e1f56c3454496822295399d5bc30c8682be06 100644
--- a/src/main/java/eu/hbp/mip/models/DTOs/ExaremeAlgorithmDTO.java
+++ b/src/main/java/eu/hbp/mip/models/DTOs/ExaremeAlgorithmDTO.java
@@ -3,6 +3,7 @@ package eu.hbp.mip.models.DTOs;
 import com.google.gson.annotations.SerializedName;
 import lombok.AllArgsConstructor;
 import lombok.Data;
+import lombok.NoArgsConstructor;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -27,7 +28,7 @@ public class ExaremeAlgorithmDTO {
     private List<ExaremeAlgorithmRequestParamDTO> parameters;
 
     @SerializedName("preprocessing")
-    private List<Transformer> preprocessing;
+    private List<ExaremeTransformerDTO> preprocessing;
 
     public ExaremeAlgorithmDTO() {
 
@@ -55,10 +56,10 @@ public class ExaremeAlgorithmDTO {
             });
         }
         this.parameters = parameters;
-        List<Transformer> preprocessing = new ArrayList<>();
+        List<ExaremeTransformerDTO> preprocessing = new ArrayList<>();
         if (exareme2Algorithm.getPreprocessing().isPresent()) {
             exareme2Algorithm.getPreprocessing().get().forEach(exareme2TransformerDTO -> {
-                Transformer transformer = new Transformer(exareme2TransformerDTO);
+                ExaremeTransformerDTO transformer = new ExaremeTransformerDTO(exareme2TransformerDTO);
                 preprocessing.add(transformer);
             });
             this.preprocessing = preprocessing;
@@ -67,8 +68,9 @@ public class ExaremeAlgorithmDTO {
 
 
     @Data
+    @NoArgsConstructor
     @AllArgsConstructor
-    public static class Transformer {
+    public static class ExaremeTransformerDTO {
         @SerializedName("name")
         private String name;
 
@@ -81,8 +83,7 @@ public class ExaremeAlgorithmDTO {
         @SerializedName("parameters")
         private List<ExaremeAlgorithmRequestParamDTO> parameters;
 
-
-        public Transformer(Exareme2AlgorithmDTO.Exareme2TransformerDTO transformerDTO) {
+        public ExaremeTransformerDTO(Exareme2AlgorithmDTO.Exareme2TransformerDTO transformerDTO) {
             this.name = transformerDTO.getName().toUpperCase();
             this.label = transformerDTO.getLabel();
             this.desc = transformerDTO.getDesc();
diff --git a/src/main/java/eu/hbp/mip/services/ExperimentService.java b/src/main/java/eu/hbp/mip/services/ExperimentService.java
index 9fe7e4cf9e507f3ed8b2ae4895bf7b098330a304..ff1f2027714838bc7e8f3ea629de79e3ec69dcdb 100644
--- a/src/main/java/eu/hbp/mip/services/ExperimentService.java
+++ b/src/main/java/eu/hbp/mip/services/ExperimentService.java
@@ -356,20 +356,25 @@ public class ExperimentService {
     private void algorithmParametersLogging(ExperimentDTO experimentDTO, Logger logger) {
         String algorithmName = experimentDTO.getAlgorithm().getName();
         StringBuilder parametersLogMessage = new StringBuilder(", Parameters:\n");
-        experimentDTO.getAlgorithm().getParameters().forEach(
-                params -> parametersLogMessage
-                        .append("  ")
-                        .append(params.getLabel())
-                        .append(" -> ")
-                        .append(params.getValue())
-                        .append("\n"));
-        experimentDTO.getAlgorithm().getPreprocessing().forEach( transformer ->
-                {
-                    parametersLogMessage
+        if (experimentDTO.getAlgorithm().getParameters() != null){
+            experimentDTO.getAlgorithm().getParameters().forEach(
+                    params -> parametersLogMessage
                             .append("  ")
-                            .append(transformer.getLabel())
+                            .append(params.getLabel())
                             .append(" -> ")
-                            .append("\n");
+                            .append(params.getValue())
+                            .append("\n"));
+        }
+        if (experimentDTO.getAlgorithm().getPreprocessing() != null) {
+            experimentDTO.getAlgorithm().getPreprocessing().forEach(transformer ->
+            {
+                parametersLogMessage
+                        .append("  ")
+                        .append(transformer.getLabel())
+                        .append(" -> ")
+                        .append("\n");
+
+                if (transformer.getParameters() != null) {
                     transformer.getParameters().forEach(
                             transformerParams -> parametersLogMessage
                                     .append("        ")
@@ -378,8 +383,9 @@ public class ExperimentService {
                                     .append(transformerParams.getValue())
                                     .append("\n"));
                     parametersLogMessage.append("\n");
-                });
-
+                }
+            });
+        }
 
         logger.LogUserAction("Executing " + algorithmName + parametersLogMessage);
     }