diff --git a/org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/context/TerminologyCache.java b/org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/context/TerminologyCache.java
index 4ea977d42..9556d1ebd 100644
--- a/org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/context/TerminologyCache.java
+++ b/org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/context/TerminologyCache.java
@@ -38,7 +38,6 @@ import java.io.IOException;
 import java.io.OutputStreamWriter;
 import java.util.*;
 
-import lombok.AccessLevel;
 import lombok.Getter;
 import lombok.Setter;
 import lombok.experimental.Accessors;
@@ -85,6 +84,8 @@ public class TerminologyCache {
   private static final String CAPABILITY_STATEMENT_TITLE = ".capabilityStatement";
   private static final String TERMINOLOGY_CAPABILITIES_TITLE = ".terminologyCapabilities";
 
+  private SystemNameKeyGenerator systemNameKeyGenerator = new SystemNameKeyGenerator();
+
   public class CacheToken {
     @Getter
     private String name;
@@ -96,13 +97,48 @@ public class TerminologyCache {
     private boolean hasVersion;
 
     public void setName(String n) {
+      String systemName = getSystemNameKeyGenerator().getNameForSystem(n);
       if (name == null)
-        name = n;
-      else if (!n.equals(name))
+        name = systemName;
+      else if (!systemName.equals(name))
         name = NAME_FOR_NO_SYSTEM;
     }
   }
 
+  protected SystemNameKeyGenerator getSystemNameKeyGenerator() {
+    return systemNameKeyGenerator;
+  }
+  public class SystemNameKeyGenerator {
+    public String getNameForSystem(String system) {
+      if (system.equals("http://snomed.info/sct"))
+        return "snomed";
+      if (system.equals("http://www.nlm.nih.gov/research/umls/rxnorm"))
+        return "rxnorm";
+      if (system.equals("http://loinc.org"))
+        return "loinc";
+      if (system.equals("http://unitsofmeasure.org"))
+        return "ucum";
+      if (system.startsWith("http://hl7.org/fhir/sid/"))
+        return system.substring(24).replace("/", "");
+      if (system.startsWith("urn:iso:std:iso:"))
+        return "iso"+system.substring(16).replace(":", "");
+      if (system.startsWith("http://terminology.hl7.org/CodeSystem/"))
+        return system.substring(38).replace("/", "").replace('|','X');
+      if (system.startsWith("http://hl7.org/fhir/"))
+        return system.substring(20).replace("/", "");
+      if (system.equals("urn:ietf:bcp:47"))
+        return "lang";
+      if (system.equals("urn:ietf:bcp:13"))
+        return "mimetypes";
+      if (system.equals("urn:iso:std:iso:11073:10101"))
+        return "11073";
+      if (system.equals("http://dicom.nema.org/resources/ontology/DCM"))
+        return "dicom";
+      return system.replace("/", "_").replace(":", "_").replace("?", "X").replace("#", "X");
+    }
+  }
+
+
   private class CacheEntry {
     private String request;
     private boolean persistent;
@@ -185,7 +221,7 @@ public class TerminologyCache {
   public CacheToken generateValidationToken(ValidationOptions options, Coding code, ValueSet vs) {
     CacheToken ct = new CacheToken();
     if (code.hasSystem()) {
-      ct.name = getNameForSystem(code.getSystem());
+      ct.setName(code.getSystem());
       ct.hasVersion = code.hasVersion();
     }
     else
@@ -226,7 +262,7 @@ public class TerminologyCache {
     CacheToken ct = new CacheToken();
     for (Coding c : code.getCoding()) {
       if (c.hasSystem()) {
-        ct.setName(getNameForSystem(c.getSystem()));
+        ct.setName(c.getSystem());
         ct.hasVersion = c.hasVersion();
       }
     }
@@ -287,53 +323,31 @@ public class TerminologyCache {
     if (vs != null) {
       for (ConceptSetComponent inc : vs.getCompose().getInclude()) {
         if (inc.hasSystem()) {
-          ct.setName(getNameForSystem(inc.getSystem()));
+          ct.setName(inc.getSystem());
           ct.hasVersion = inc.hasVersion();
         }
       }
       for (ConceptSetComponent inc : vs.getCompose().getExclude()) {
         if (inc.hasSystem()) {
-          ct.setName(getNameForSystem(inc.getSystem()));
+          ct.setName(inc.getSystem());
           ct.hasVersion = inc.hasVersion();
         }
       }
       for (ValueSetExpansionContainsComponent inc : vs.getExpansion().getContains()) {
         if (inc.hasSystem()) {
-          ct.setName(getNameForSystem(inc.getSystem()));
+          ct.setName(inc.getSystem());
           ct.hasVersion = inc.hasVersion();
         }
       }
     }
   }
 
-  private String getNameForSystem(String system) {
-    if (system.equals("http://snomed.info/sct"))
-      return "snomed";
-    if (system.equals("http://www.nlm.nih.gov/research/umls/rxnorm"))
-      return "rxnorm";
-    if (system.equals("http://loinc.org"))
-      return "loinc";
-    if (system.equals("http://unitsofmeasure.org"))
-      return "ucum";
-    if (system.startsWith("http://hl7.org/fhir/sid/"))
-      return system.substring(24).replace("/", "");
-    if (system.startsWith("urn:iso:std:iso:"))
-      return "iso"+system.substring(16).replace(":", "");
-    if (system.startsWith("http://terminology.hl7.org/CodeSystem/"))
-      return system.substring(38).replace("/", "").replace('|','X');
-    if (system.startsWith("http://hl7.org/fhir/"))
-      return system.substring(20).replace("/", "");
-    if (system.equals("urn:ietf:bcp:47"))
-      return "lang";
-    if (system.equals("urn:ietf:bcp:13"))
-      return "mimetypes";
-    if (system.equals("urn:iso:std:iso:11073:10101"))
-      return "11073";
-    if (system.equals("http://dicom.nema.org/resources/ontology/DCM"))
-      return "dicom";
-    return system.replace("/", "_").replace(":", "_").replace("?", "X").replace("#", "X");
+  private String normalizeSystemPath(String path) {
+    return path.replace("/", "").replace('|','X');
   }
 
+
+
   public NamedCache getNamedCache(CacheToken cacheToken) {
 
     final String cacheName = cacheToken.name == null ? "null" : cacheToken.name;
@@ -687,7 +701,7 @@ public class TerminologyCache {
 
   public void removeCS(String url) {
     synchronized (lock) {
-      String name = getNameForSystem(url);
+      String name = getSystemNameKeyGenerator().getNameForSystem(url);
       if (caches.containsKey(name)) {
         caches.remove(name);
       }