[Bug]: Error when adding two pipeline mappings.

[CarlosJuncher03]

Apache Hop version?

2.18

Java version?

21

Operating system

Linux

What happened?

When creating a pipeline mapping and calling another pipeline mapping within it, in cases where both have the same name in the mapping input transformation, the second pipeline displays this error even if everything is configured correctly.

"
2026/03/17 13:09:21 [Basic] Hop - Pipeline opened. 2026/03/17 13:09:21 [Basic] Hop - Launching pipeline [mapping_rest_paginado]... 2026/03/17 13:09:21 [Basic] Hop - Started executing pipeline 'mapping_rest_paginado'. 2026/03/17 13:09:21 [Basic] mapping_rest_paginado - Executing this pipeline using the Local Pipeline Engine with run configuration 'local' 2026/03/17 13:09:21 [Basic] mapping_rest_paginado - Execution started for pipeline [mapping_rest_paginado] 2026/03/17 13:09:21 [Basic] mapping_rest - Executing this pipeline using the Local Pipeline Engine with run configuration 'local' 2026/03/17 13:09:21 [Basic] mapping_rest - Execution started for pipeline [mapping_rest] 2026/03/17 13:09:21 [Error] Mapping Rest.0 - Unable to load the mapping pipeline because of an error : org.apache.hop.core.exception.HopException: 2026/03/17 13:09:21 [Error] Mapping Rest.0 - The simple mapping transform needs one Mapping Input transform to write to in the sub-pipeline 2026/03/17 13:09:21 [Error] Mapping Rest.0 - org.apache.hop.core.exception.HopException: 2026/03/17 13:09:21 [Error] Mapping Rest.0 - The simple mapping transform needs one Mapping Input transform to write to in the sub-pipeline 2026/03/17 13:09:21 [Error] Mapping Rest.0 - 2026/03/17 13:09:21 [Error] Mapping Rest.0 - at org.apache.hop.pipeline.transforms.mapping.SimpleMapping.prepareMappingExecution(SimpleMapping.java:212) 2026/03/17 13:09:21 [Error] Mapping Rest.0 - at org.apache.hop.pipeline.transforms.mapping.SimpleMapping.init(SimpleMapping.java:280) 2026/03/17 13:09:21 [Error] Mapping Rest.0 - at org.apache.hop.pipeline.transform.TransformInitThread.run(TransformInitThread.java:74) 2026/03/17 13:09:21 [Error] Mapping Rest.0 - at java.base/java.lang.Thread.run(Thread.java:1583) 2026/03/17 13:09:21 [Error] Mapping Rest.0 - Error initializing transform [Mapping Rest] 2026/03/17 13:09:21 [Error] mapping_rest_paginado - Transform [Mapping Rest.0] failed to initialize! 2026/03/17 13:09:21 [Error] Hop - mapping_rest_paginado: preparing pipeline execution failed 2026/03/17 13:09:21 [Error] Hop - org.apache.hop.core.exception.HopException: 2026/03/17 13:09:21 [Error] Hop - We failed to initialize at least one transform. Execution can not begin! 2026/03/17 13:09:21 [Error] Hop - 2026/03/17 13:09:21 [Error] Hop - 2026/03/17 13:09:21 [Error] Hop - at org.apache.hop.pipeline.Pipeline.prepareExecution(Pipeline.java:1123) 2026/03/17 13:09:21 [Error] Hop - at org.apache.hop.pipeline.engines.local.LocalPipelineEngine.prepareExecution(LocalPipelineEngine.java:236) 2026/03/17 13:09:21 [Error] Hop - at org.apache.hop.ui.hopgui.file.pipeline.HopGuiPipelineGraph.lambda$preparePipeline$21(HopGuiPipelineGraph.java:4815) 2026/03/17 13:09:21 [Error] Hop - at java.base/java.lang.Thread.run(Thread.java:1583)
"

Issue Priority

Priority: 3

Issue Component

Component: Transforms