diff --git a/src/main/java/org/codejive/properties/Properties.java b/src/main/java/org/codejive/properties/Properties.java
index 2544a33..28721fe 100644
--- a/src/main/java/org/codejive/properties/Properties.java
+++ b/src/main/java/org/codejive/properties/Properties.java
@@ -2,12 +2,36 @@
 
 import static org.codejive.properties.PropertiesParser.unescape;
 
-import java.io.*;
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.io.OutputStream;
+import java.io.OutputStreamWriter;
+import java.io.PrintStream;
+import java.io.PrintWriter;
+import java.io.Reader;
+import java.io.Writer;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.StandardOpenOption;
-import java.util.*;
+import java.util.AbstractMap;
+import java.util.AbstractSet;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.Enumeration;
+import java.util.Iterator;
+import java.util.LinkedHashMap;
+import java.util.LinkedHashSet;
+import java.util.List;
+import java.util.NoSuchElementException;
+import java.util.Objects;
+import java.util.Set;
+import java.util.Spliterator;
+import java.util.Spliterators;
 import java.util.function.Function;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
@@ -68,7 +92,7 @@ public String getProperty(String key) {
      * @param key the key to look up.
      * @param defaultValue the value to return if no mapping was found for the key.
      * @return the value in this property list with the specified key value or the value of <code>
-     *     defaultValue</code>.
+     * defaultValue</code>.
      */
     public String getProperty(String key, String defaultValue) {
         if (containsKey(key)) {
@@ -773,6 +797,18 @@ public List<PropertiesParser.Token> next() {
                 Spliterators.spliterator(iter, tokens.size(), Spliterator.SORTED), false);
     }
 
+    /**
+     * Copies all entries from the <code>java.util.Properties</code> object to this object
+     *
+     * @param properties a <code>java.util.Properties</code> object
+     * @throws NullPointerException if the properties parameter is null
+     */
+    public void putAll(java.util.Properties properties) {
+        for (Entry<Object, Object> entry : properties.entrySet()) {
+            put(entry.getKey().toString(), entry.getValue().toString());
+        }
+    }
+
     /**
      * Returns a <code>java.util.Properties</code> with the same contents as this object. The
      * information is a copy, changes to one Properties object will not affect the other.
diff --git a/src/test/java/org/codejive/properties/TestProperties.java b/src/test/java/org/codejive/properties/TestProperties.java
index 4c51c72..ab2ee5e 100644
--- a/src/test/java/org/codejive/properties/TestProperties.java
+++ b/src/test/java/org/codejive/properties/TestProperties.java
@@ -1,8 +1,13 @@
 package org.codejive.properties;
 
-import static org.assertj.core.api.Assertions.*;
-
-import java.io.*;
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+
+import java.io.IOException;
+import java.io.PrintWriter;
+import java.io.Reader;
+import java.io.StringReader;
+import java.io.StringWriter;
 import java.net.URISyntaxException;
 import java.nio.file.Files;
 import java.nio.file.Path;
@@ -691,6 +696,15 @@ void testMultiDelim() throws IOException, URISyntaxException {
         assertThat(sw.toString()).isEqualTo(readAll(getResource("/test-multidelim.properties")));
     }
 
+    @Test
+    void testPutAll() {
+        Properties p = new Properties();
+        java.util.Properties ju = new java.util.Properties();
+        ju.setProperty("foo", "bar");
+        p.putAll(ju);
+        assertThat(p.getProperty("foo")).isEqualTo("bar");
+    }
+
     private Path getResource(String name) throws URISyntaxException {
         return Paths.get(getClass().getResource(name).toURI());
     }