No need to end exception messages with an exclamation!

Author: garydgregory

src/main/java/org/apache/commons/configuration2/AbstractConfiguration.java

@@ -177,7 +177,7 @@ private static <T> Collection<T> handleDefaultCollection(final Collection<T> tar
      * @param key the key (to be part of the error message)
      */
     private static void throwMissingPropertyException(final String key) {
-        throw new NoSuchElementException(String.format("Key '%s' does not map to an existing object!", key));
+        throw new NoSuchElementException(String.format("Key '%s' does not map to an existing object.", key));
     }
 
     /** The list delimiter handler. */
@@ -795,7 +795,7 @@ public Duration getDuration(final String key, final Duration defaultValue) {
     public String getEncodedString(final String key) {
         final ConfigurationDecoder decoder = getConfigurationDecoder();
         if (decoder == null) {
-            throw new IllegalStateException("No default ConfigurationDecoder defined!");
+            throw new IllegalStateException("No default ConfigurationDecoder defined.");
         }
         return getEncodedString(key, decoder);
     }
@@ -808,7 +808,7 @@ public String getEncodedString(final String key) {
     @Override
     public String getEncodedString(final String key, final ConfigurationDecoder decoder) {
         if (decoder == null) {
-            throw new IllegalArgumentException("ConfigurationDecoder must not be null!");
+            throw new IllegalArgumentException("ConfigurationDecoder must not be null.");
         }
 
         final String value = getString(key);
@@ -1313,7 +1313,7 @@ public void setConfigurationDecoder(final ConfigurationDecoder configurationDeco
      */
     public void setConversionHandler(final ConversionHandler conversionHandler) {
         if (conversionHandler == null) {
-            throw new IllegalArgumentException("ConversionHandler must not be null!");
+            throw new IllegalArgumentException("ConversionHandler must not be null.");
         }
         this.conversionHandler = conversionHandler;
     }
@@ -1379,7 +1379,7 @@ public final void setInterpolator(final ConfigurationInterpolator ci) {
      */
     public void setListDelimiterHandler(final ListDelimiterHandler listDelimiterHandler) {
         if (listDelimiterHandler == null) {
-            throw new IllegalArgumentException("List delimiter handler must not be null!");
+            throw new IllegalArgumentException("List delimiter handler must not be null.");
         }
         this.listDelimiterHandler = listDelimiterHandler;
     }

src/main/java/org/apache/commons/configuration2/CombinedConfiguration.java

@@ -399,13 +399,13 @@ public void addConfiguration(final Configuration config, final String name) {
      */
     public void addConfiguration(final Configuration config, final String name, final String at) {
         if (config == null) {
-            throw new IllegalArgumentException("Added configuration must not be null!");
+            throw new IllegalArgumentException("Added configuration must not be null.");
         }
 
         beginWrite(true);
         try {
             if (name != null && namedConfigurations.containsKey(name)) {
-                throw new ConfigurationRuntimeException("A configuration with the name '" + name + "' already exists in this combined configuration!");
+                throw new ConfigurationRuntimeException("A configuration with the name '" + name + "' already exists in this combined configuration.");
             }
 
             final ConfigData cd = new ConfigData(config, name, at);
@@ -706,7 +706,7 @@ private int getNumberOfConfigurationsInternal() {
      */
     public Configuration getSource(final String key) {
         if (key == null) {
-            throw new IllegalArgumentException("Key must not be null!");
+            throw new IllegalArgumentException("Key must not be null.");
         }
 
         final Set<Configuration> sources = getSources(key);
@@ -716,7 +716,7 @@ public Configuration getSource(final String key) {
         final Iterator<Configuration> iterator = sources.iterator();
         final Configuration source = iterator.next();
         if (iterator.hasNext()) {
-            throw new IllegalArgumentException("The key " + key + " is defined by multiple sources!");
+            throw new IllegalArgumentException("The key " + key + " is defined by multiple sources.");
         }
         return source;
     }
@@ -900,7 +900,7 @@ public void setConversionExpressionEngine(final ExpressionEngine conversionExpre
      */
     public void setNodeCombiner(final NodeCombiner nodeCombiner) {
         if (nodeCombiner == null) {
-            throw new IllegalArgumentException("Node combiner must not be null!");
+            throw new IllegalArgumentException("Node combiner must not be null.");
         }
 
         beginWrite(true);

src/main/java/org/apache/commons/configuration2/CompositeConfiguration.java

@@ -409,14 +409,14 @@ protected Object getPropertyInternal(final String key) {
      */
     public Configuration getSource(final String key) {
         if (key == null) {
-            throw new IllegalArgumentException("Key must not be null!");
+            throw new IllegalArgumentException("Key must not be null.");
         }
 
         Configuration source = null;
         for (final Configuration conf : configList) {
             if (conf.containsKey(key)) {
                 if (source != null) {
-                    throw new IllegalArgumentException("The key " + key + " is defined by multiple sources!");
+                    throw new IllegalArgumentException("The key " + key + " is defined by multiple sources.");
                 }
                 source = conf;
             }

src/main/java/org/apache/commons/configuration2/ConfigurationLookup.java

@@ -44,7 +44,7 @@ public class ConfigurationLookup implements Lookup {
      */
     public ConfigurationLookup(final ImmutableConfiguration config) {
         if (config == null) {
-            throw new IllegalArgumentException("Configuration must not be null!");
+            throw new IllegalArgumentException("Configuration must not be null.");
         }
         configuration = config;
     }

src/main/java/org/apache/commons/configuration2/ConfigurationUtils.java

@@ -219,7 +219,7 @@ public static Object cloneIfPossible(final Object obj) {
      */
     public static Synchronizer cloneSynchronizer(final Synchronizer sync) {
         if (sync == null) {
-            throw new IllegalArgumentException("Synchronizer must not be null!");
+            throw new IllegalArgumentException("Synchronizer must not be null.");
         }
         if (NoOpSynchronizer.INSTANCE == sync) {
             return sync;
@@ -401,7 +401,7 @@ public static void dump(final ImmutableConfiguration configuration, final PrintW
      */
     public static void enableRuntimeExceptions(final Configuration src) {
         if (!(src instanceof EventSource)) {
-            throw new IllegalArgumentException("Configuration must implement EventSource!");
+            throw new IllegalArgumentException("Configuration must implement EventSource.");
         }
         ((EventSource) src).addEventListener(ConfigurationErrorEvent.ANY, event -> {
             // Throw a runtime exception

src/main/java/org/apache/commons/configuration2/ConfigurationXMLReader.java

@@ -234,7 +234,7 @@ public void parse(final String systemId) throws IOException, SAXException {
      */
     protected void parseConfiguration() throws IOException, SAXException {
         if (getParsedConfiguration() == null) {
-            throw new IOException("No configuration specified!");
+            throw new IOException("No configuration specified.");
         }
 
         if (getContentHandler() != null) {

src/main/java/org/apache/commons/configuration2/DynamicCombinedConfiguration.java

@@ -706,7 +706,7 @@ public Short getShort(final String key, final Short defaultValue) {
     @Override
     public Configuration getSource(final String key) {
         if (key == null) {
-            throw new IllegalArgumentException("Key must not be null!");
+            throw new IllegalArgumentException("Key must not be null.");
         }
         return getCurrentConfig().getSource(key);
     }
@@ -892,7 +892,7 @@ public void setLoggerName(final String name) {
     @Override
     public void setNodeCombiner(final NodeCombiner nodeCombiner) {
         if (nodeCombiner == null) {
-            throw new IllegalArgumentException("Node combiner must not be null!");
+            throw new IllegalArgumentException("Node combiner must not be null.");
         }
         this.nodeCombiner = nodeCombiner;
         invalidateAll();

src/main/java/org/apache/commons/configuration2/EnvironmentConfiguration.java

@@ -63,7 +63,7 @@ public EnvironmentConfiguration() {
      */
     @Override
     protected void addPropertyDirect(final String key, final Object value) {
-        throw new UnsupportedOperationException("EnvironmentConfiguration is read-only!");
+        throw new UnsupportedOperationException("EnvironmentConfiguration is read-only.");
     }
 
     /**
@@ -72,7 +72,7 @@ protected void addPropertyDirect(final String key, final Object value) {
      */
     @Override
     protected void clearInternal() {
-        throw new UnsupportedOperationException("EnvironmentConfiguration is read-only!");
+        throw new UnsupportedOperationException("EnvironmentConfiguration is read-only.");
     }
 
     /**
@@ -83,6 +83,6 @@ protected void clearInternal() {
      */
     @Override
     protected void clearPropertyDirect(final String key) {
-        throw new UnsupportedOperationException("EnvironmentConfiguration is read-only!");
+        throw new UnsupportedOperationException("EnvironmentConfiguration is read-only.");
     }
 }

src/main/java/org/apache/commons/configuration2/ImmutableConfigurationInvocationHandler.java

@@ -82,7 +82,7 @@ public Object next() {
          */
         @Override
         public void remove() {
-            throw new UnsupportedOperationException("remove() operation not supported!");
+            throw new UnsupportedOperationException("remove() operation not supported.");
         }
     }
 

src/main/java/org/apache/commons/configuration2/PropertiesConfigurationLayout.java

@@ -489,7 +489,7 @@ private String extractComment(final List<String> commentLines, final int from, f
      */
     private PropertyLayoutData fetchLayoutData(final String key) {
         if (key == null) {
-            throw new IllegalArgumentException("Property key must not be null!");
+            throw new IllegalArgumentException("Property key must not be null.");
         }
 
         // PropertyLayoutData defaults to singleLine = true