Initial Commit

src/main/java/net/locusworks/common/properties/ImmutableProperties.java

@@ -0,0 +1,31 @@
+package net.locusworks.common.properties;
+
+import java.util.Properties;
+
+public class ImmutableProperties extends Properties {
+
+  private static final long serialVersionUID = 65942088008978137L;
+  
+  public ImmutableProperties() {
+   super();
+  }
+  
+  public ImmutableProperties(Properties props) {
+    super();
+    if (props == null || props.isEmpty()) return;
+    
+    props.entrySet().forEach(item -> this.put(item.getKey(), item.getValue()));
+  }
+  
+  @Override
+  public synchronized Object setProperty(String key, String value) {
+    return put(key, value);
+  }
+  
+  public synchronized Object put(Object key, Object value) {
+    if (containsKey(key)) 
+      throw new RuntimeException("Cannot change key value once its set: " + key);
+    return super.put(key, value);
+  }
+
+}