common/src/main/java/org/apache/nemo/common/dag/DAGBuilder.java [168:176]:
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    } else {
      this.buildWithoutSourceSinkCheck().storeJSON("debug", "errored_ir", "Errored IR");
      throw new IllegalVertexOperationException("The DAG does not contain"
        + (vertices.contains(src) ? "" : " [source]") + (vertices.contains(dst) ? "" : " [destination]")
        + " of the edge: [" + (src == null ? null : src.getId())
        + "]->[" + (dst == null ? null : dst.getId()) + "] in "
        + vertices.stream().map(V::getId).collect(Collectors.toSet()));
    }
    return this;
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common/src/main/java/org/apache/nemo/common/dag/DAGBuilder.java [237:245]:
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    } else {
      this.buildWithoutSourceSinkCheck().storeJSON("debug", "errored_ir", "Errored IR");
      throw new IllegalVertexOperationException("The DAG does not contain"
        + (vertices.contains(src) ? "" : " [source]") + (vertices.contains(dst) ? "" : " [destination]")
        + " of the edge: [" + (src == null ? null : src.getId())
        + "]->[" + (dst == null ? null : dst.getId()) + "] in "
        + vertices.stream().map(V::getId).collect(Collectors.toSet()));
    }
    return this;
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