Internal refactoring

Author: garydgregory

src/main/java/org/apache/commons/io/output/WriterOutputStream.java

@@ -137,7 +137,7 @@ public Builder() {
          */
         @Override
         public WriterOutputStream get() throws IOException {
-            return new WriterOutputStream(getWriter(), charsetDecoder, getBufferSize(), writeImmediately);
+            return new WriterOutputStream(this);
         }
 
         @Override
@@ -245,6 +245,11 @@ private static void checkIbmJdkWithBrokenUTF16(final Charset charset) {
      */
     private final CharBuffer decoderOut;
 
+    @SuppressWarnings("resource") // caller closes.
+    private WriterOutputStream(final Builder builder) throws IOException {
+        this(builder.getWriter(), builder.charsetDecoder, builder.getBufferSize(), builder.writeImmediately);
+    }
+
     /**
      * Constructs a new {@link WriterOutputStream} that uses the virtual machine's {@link Charset#defaultCharset() default charset} and with a default output
      * buffer size of {@value #BUFFER_SIZE} characters. The output buffer will only be flushed when it overflows or when {@link #flush()} or {@link #close()} is