Removed a faulty sanity check

pmml-model/src/main/java/org/jpmml/model/PMMLOutputStream.java

@@ -64,13 +64,9 @@ public void write(int b) throws IOException {
 				} else
 
 				if(string.endsWith(">")){
-					String updatedString = string.replace(Version.PMML_4_4.getNamespaceURI(), this.version.getNamespaceURI());
+					string = string.replace(Version.PMML_4_4.getNamespaceURI(), this.version.getNamespaceURI());
 
-					if(Objects.equals(string, updatedString)){
-						throw new IllegalStateException();
-					}
-
-					super.out.write(updatedString.getBytes("UTF-8"));
+					super.out.write(string.getBytes("UTF-8"));
 
 					this.buffer = null;
 				} else

pmml-model/src/test/java/org/jpmml/model/PMMLOutputStreamTest.java

@@ -0,0 +1,54 @@
+/*
+ * Copyright (c) 2024 Villu Ruusmann
+ */
+package org.jpmml.model;
+
+import java.io.ByteArrayOutputStream;
+import java.io.OutputStream;
+
+import javax.xml.transform.stream.StreamResult;
+
+import org.dmg.pmml.PMML;
+import org.dmg.pmml.Version;
+import org.junit.Test;
+
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+
+public class PMMLOutputStreamTest {
+
+	@Test
+	public void marshal() throws Exception {
+		PMML pmml = new PMML();
+
+		try {
+			marshal(pmml, Version.XPMML);
+
+			fail();
+		} catch(IllegalArgumentException iae){
+			// Ignored
+		}
+
+		String string = marshal(pmml, Version.PMML_4_4);
+
+		assertTrue(string.contains(Version.PMML_4_4.getNamespaceURI()));
+		assertFalse(string.contains(Version.PMML_4_3.getNamespaceURI()));
+
+		string = marshal(pmml, Version.PMML_4_3);
+
+		assertFalse(string.contains(Version.PMML_4_4.getNamespaceURI()));
+		assertTrue(string.contains(Version.PMML_4_3.getNamespaceURI()));
+	}
+
+	static
+	private String marshal(PMML pmml, Version version) throws Exception {
+		ByteArrayOutputStream buffer = new ByteArrayOutputStream();
+
+		try(OutputStream os = new PMMLOutputStream(buffer, version)){
+			JAXBUtil.marshalPMML(pmml, new StreamResult(os));
+		}
+
+		return buffer.toString("UTF-8");
+	}
+}