Add asReader method

git-svn-id: https://svn.apache.org/repos/asf/jakarta/commons/proper/lang/trunk@227320 13f79535-47bb-0310-9956-ffa450edef68

src/java/org/apache/commons/lang/text/StrBuilder.java

@@ -15,6 +15,8 @@
  */
 package org.apache.commons.lang.text;
 
+import java.io.CharArrayReader;
+import java.io.Reader;
 import java.util.Collection;
 import java.util.Iterator;
 
@@ -1477,6 +1479,22 @@ public class StrBuilder implements Cloneable {
         return this;
     }
 
+    //-----------------------------------------------------------------------
+    /**
+     * Gets the contents of this builder as a Reader.
+     * <p>
+     * This method allows the contents of the builder to be read
+     * using any standard method that expects a Reader.
+     * The current implementation returns a CharArrayReader, but
+     * you should not rely on this.
+     *
+     * @return a reader
+     */
+    public Reader asReader() {
+        return new CharArrayReader(buffer, 0, size);
+    }
+
+    //-----------------------------------------------------------------------
 //    /**
 //     * Gets a String version of the string builder by calling the internal
 //     * constructor of String by reflection.

src/test/org/apache/commons/lang/text/StrBuilderTest.java

@@ -16,6 +16,7 @@
 
 package org.apache.commons.lang.text;
 
+import java.io.Reader;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
@@ -1601,4 +1602,17 @@ public class StrBuilderTest extends TestCase {
             fail();
         } catch (StringIndexOutOfBoundsException e) {}
     }
+
+    //-----------------------------------------------------------------------
+    public void testAsReader() throws Exception {
+        StrBuilder sb = new StrBuilder ("some text");
+        Reader reader = sb.asReader();
+        char[] buf = new char[40];
+        assertEquals(9, reader.read(buf));
+        assertEquals("some text", new String(buf, 0, 9));
+        
+        buf = new char[40];
+        assertEquals(-1, reader.read(buf));
+    }
+
 }