Summary

Clarify the flush methods in java.io classes CharArrayWriter and StringWriter do nothing.

Problem

The specification of flush() in the two indicated classes is not explicit about the fact that the methods have no effect.

Solution

To the specification of each flush() method add the sentence

The {@code flush} method of {@code <ClassName/>} does nothing.

Specification

--- a/src/java.base/share/classes/java/io/CharArrayWriter.java
+++ b/src/java.base/share/classes/java/io/CharArrayWriter.java
@@ -276,6 +276,8 @@ public class CharArrayWriter extends Writer {

     /**
      * Flush the stream.
+     *
+     * <p> The {@code flush} method of {@code CharArrayWriter} does nothing.
      */
     public void flush() { }

diff --git a/src/java.base/share/classes/java/io/StringWriter.java b/src/java.base/share/classes/java/io/StringWriter.java
index 16eed62d7bb..30654230ca6 100644
--- a/src/java.base/share/classes/java/io/StringWriter.java
+++ b/src/java.base/share/classes/java/io/StringWriter.java
@@ -229,6 +229,8 @@ public class StringWriter extends Writer {

     /**
      * Flush the stream.
+     *
+     * <p> The {@code flush} method of {@code StringWriter} does nothing.
      */
     public void flush() {
     }