diff --git a/metafix-web/src/main/java/org/metafacture/metafix/web/FixServlet.java b/metafix-web/src/main/java/org/metafacture/metafix/web/FixServlet.java
index 16866e70..ae87a658 100644
--- a/metafix-web/src/main/java/org/metafacture/metafix/web/FixServlet.java
+++ b/metafix-web/src/main/java/org/metafacture/metafix/web/FixServlet.java
@@ -9,6 +9,7 @@
 import org.eclipse.xtext.xbase.lib.InputOutput;
 
 import java.io.IOException;
+import java.io.Reader;
 import java.io.StringReader;
 import java.nio.file.Files;
 import java.nio.file.Paths;
@@ -106,7 +107,9 @@ private boolean process(final HttpServletRequest request, final HttpServletRespo
     }
 
     private String absPathToTempFile(final String content, final String suffix) throws IOException {
-        return FixStandaloneSetup.absPathToTempFile(new StringReader(content), suffix);
+        try (Reader reader = new StringReader(content)) {
+            return FixStandaloneSetup.absPathToTempFile(reader, suffix);
+        }
     }
 
 }
diff --git a/metafix/src/jmh/java/org/metafacture/metafix/MetafixBenchmark.java b/metafix/src/jmh/java/org/metafacture/metafix/MetafixBenchmark.java
index 6ec27d2a..4f7024c3 100644
--- a/metafix/src/jmh/java/org/metafacture/metafix/MetafixBenchmark.java
+++ b/metafix/src/jmh/java/org/metafacture/metafix/MetafixBenchmark.java
@@ -25,7 +25,7 @@
 
 import org.openjdk.jmh.annotations.Param;
 
-import java.io.FileNotFoundException;
+import java.io.IOException;
 import java.io.UncheckedIOException;
 
 public class MetafixBenchmark extends FixParseBenchmark { // checkstyle-disable-line ClassDataAbstractionCoupling
@@ -57,7 +57,7 @@ public void setup() {
         try {
             metafix = new Metafix(fixFile);
         }
-        catch (final FileNotFoundException e) {
+        catch (final IOException e) {
             throw new UncheckedIOException(e);
         }
 
diff --git a/metafix/src/main/java/org/metafacture/metafix/Metafix.java b/metafix/src/main/java/org/metafacture/metafix/Metafix.java
index f335e94d..d730c62f 100644
--- a/metafix/src/main/java/org/metafacture/metafix/Metafix.java
+++ b/metafix/src/main/java/org/metafacture/metafix/Metafix.java
@@ -31,7 +31,6 @@
 import org.slf4j.LoggerFactory;
 
 import java.io.Closeable;
-import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.io.Reader;
 import java.io.StringReader;
@@ -104,11 +103,11 @@ public Metafix(final Map<String, String> newVars) {
         recordTransformer = null;
     }
 
-    public Metafix(final String fixDef) throws FileNotFoundException {
+    public Metafix(final String fixDef) throws IOException {
         this(fixDef, NO_VARS);
     }
 
-    public Metafix(final String fixDef, final Map<String, String> vars) throws FileNotFoundException {
+    public Metafix(final String fixDef, final Map<String, String> vars) throws IOException {
         init(vars);
 
         if (isFixFile(fixDef)) {
@@ -116,7 +115,9 @@ public Metafix(final String fixDef, final Map<String, String> vars) throws FileN
             recordTransformer = getRecordTransformer(fixDef);
         }
         else {
-            recordTransformer = getRecordTransformer(new StringReader(fixDef));
+            try (Reader reader = new StringReader(fixDef)) {
+                recordTransformer = getRecordTransformer(reader);
+            }
         }
     }
 
@@ -475,4 +476,3 @@ protected void log(final MetafactureException exception, final BiConsumer<String
 
     }
 }
-
diff --git a/metafix/src/main/java/org/metafacture/metafix/MetafixStreamAnalyzer.java b/metafix/src/main/java/org/metafacture/metafix/MetafixStreamAnalyzer.java
index 67a77b0c..e7fa9fdf 100644
--- a/metafix/src/main/java/org/metafacture/metafix/MetafixStreamAnalyzer.java
+++ b/metafix/src/main/java/org/metafacture/metafix/MetafixStreamAnalyzer.java
@@ -27,7 +27,7 @@
 import org.metafacture.triples.TripleCount;
 import org.metafacture.triples.TripleSort;
 
-import java.io.FileNotFoundException;
+import java.io.IOException;
 
 /**
  * Superclass for Metafix-based analyzer modules based on triples (see {@link org.metafacture.framework.objects.Triple}).
@@ -49,7 +49,7 @@
             this.fix = new Metafix(fix);
             this.fix.setRepeatedFieldsToEntities(true);
         }
-        catch (final FileNotFoundException e) {
+        catch (final IOException e) {
             throw new MetafactureException(e);
         }
         this.countBy = countBy;
diff --git a/metafix/src/test/java/org/metafacture/metafix/MetafixScriptTest.java b/metafix/src/test/java/org/metafacture/metafix/MetafixScriptTest.java
index 7506cf01..67f3d448 100644
--- a/metafix/src/test/java/org/metafacture/metafix/MetafixScriptTest.java
+++ b/metafix/src/test/java/org/metafacture/metafix/MetafixScriptTest.java
@@ -27,7 +27,7 @@
 import org.mockito.Mockito;
 import org.mockito.junit.jupiter.MockitoExtension;
 
-import java.io.FileNotFoundException;
+import java.io.IOException;
 import java.util.Arrays;
 import java.util.Map;
 import java.util.function.Consumer;
@@ -585,7 +585,7 @@ private void assertFix(final String fixDef, final Map<String, String> vars, fina
 
             consumer.accept(metafix);
         }
-        catch (final FileNotFoundException e) {
+        catch (final IOException e) {
             throw new RuntimeException(e);
         }
     }
diff --git a/metafix/src/test/java/org/metafacture/metafix/MetafixTestHelpers.java b/metafix/src/test/java/org/metafacture/metafix/MetafixTestHelpers.java
index 9d8dcb00..ce5f7a5b 100644
--- a/metafix/src/test/java/org/metafacture/metafix/MetafixTestHelpers.java
+++ b/metafix/src/test/java/org/metafacture/metafix/MetafixTestHelpers.java
@@ -26,7 +26,6 @@
 
 import java.io.ByteArrayOutputStream;
 import java.io.File;
-import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.io.PrintStream;
 import java.nio.file.Files;
@@ -152,7 +151,7 @@ private static Metafix fix(final StreamReceiver receiver, final String fix, fina
             metafix = new Metafix(fix, vars);
             metafix.setReceiver(receiver);
         }
-        catch (final FileNotFoundException e) {
+        catch (final IOException e) {
             e.printStackTrace();
         }
         return metafix;