RandomAccessFileInputStream.available() should return 0 after the stream

is closed

Author: garydgregory

src/changes/changes.xml

@@ -78,6 +78,7 @@ The <action> type attribute can be add,update,fix,remove.
       <action dev="ggregory" type="fix"                due-to="Gary Gregory">MemoryMappedFileInputStream.available() should return 0 after the stream is closed.</action>
       <action dev="ggregory" type="fix"                due-to="Gary Gregory">MemoryMappedFileInputStream.read() should return -1 after the stream is closed.</action>
       <action dev="ggregory" type="fix"                due-to="Gary Gregory">ProxyInputStream.read() should return -1 after the stream is closed.</action>
+      <action dev="ggregory" type="fix"                due-to="Gary Gregory">RandomAccessFileInputStream.available() should return 0 after the stream is closed.</action>
       <!-- UPDATE -->
       <action dev="ggregory" type="update"             due-to="Dependabot">Bump tests commons.bytebuddy.version from 1.14.13 to 1.14.17 #615, #621, #631, #635.</action>
       <action dev="ggregory" type="update"             due-to="Dependabot">Bump tests commons-codec:commons-codec from 1.16.1 to 1.17.0.</action>

src/main/java/org/apache/commons/io/input/RandomAccessFileInputStream.java

@@ -128,6 +128,7 @@ public static Builder builder() {
         return new Builder();
     }
 
+    private boolean closed;
     private final boolean propagateClose;
     private final RandomAccessFile randomAccessFile;
 
@@ -179,7 +180,7 @@ public int available() throws IOException {
      * @throws IOException If an I/O error occurs.
      */
     public long availableLong() throws IOException {
-        return randomAccessFile.length() - randomAccessFile.getFilePointer();
+        return closed ? 0 : randomAccessFile.length() - randomAccessFile.getFilePointer();
     }
 
     @Override
@@ -188,6 +189,7 @@ public void close() throws IOException {
         if (propagateClose) {
             randomAccessFile.close();
         }
+        closed = true;
     }
 
     /**

src/test/java/org/apache/commons/io/input/RandomAccessFileInputStreamTest.java

@@ -47,13 +47,22 @@ private RandomAccessFile createRandomAccessFile() throws FileNotFoundException {
     }
 
     @Test
-    public void testAvailable() throws IOException {
+    public void testAvailableAfterOpen() throws IOException {
         try (RandomAccessFileInputStream inputStream = new RandomAccessFileInputStream(createRandomAccessFile(),
             true)) {
             assertEquals(DATA_FILE_LEN, inputStream.available());
         }
     }
 
+    @Test
+    public void testAvailableAfterClose() throws IOException {
+        try (RandomAccessFileInputStream inputStream = new RandomAccessFileInputStream(createRandomAccessFile(),
+            true)) {
+            inputStream.close();
+            assertEquals(0, inputStream.available());
+        }
+    }
+
     @Test
     public void testAvailableLong() throws IOException {
         try (RandomAccessFileInputStream inputStream = new RandomAccessFileInputStream(createRandomAccessFile(),