diff --git a/classpath/java/lang/IllegalThreadStateException.java b/classpath/java/lang/IllegalThreadStateException.java
new file mode 100644
index 0000000000..e579cd2ba8
--- /dev/null
+++ b/classpath/java/lang/IllegalThreadStateException.java
@@ -0,0 +1,20 @@
+package java.lang;
+
+public class IllegalThreadStateException extends IllegalArgumentException {
+  public IllegalThreadStateException(String message, Throwable cause) {
+    super(message, cause);
+  }
+
+  public IllegalThreadStateException(String message) {
+    this(message, null);
+  }
+
+  public IllegalThreadStateException(Throwable cause) {
+    this(null, cause);
+  }
+
+  public IllegalThreadStateException() {
+    this(null, null);
+  }
+
+}