Refactoring

- Pull up closed state
- Move checkOpen() for cleaner reuse

src/main/java/org/apache/commons/io/IOUtils.java

@@ -14,6 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package org.apache.commons.io;
 
 import java.io.BufferedInputStream;

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

@@ -27,18 +27,6 @@
  */
 public abstract class AbstractInputStream extends InputStream {
 
-    /**
-     * Throws an IOException on false input.
-     *
-     * @param isOpen whether the stream is open or not.
-     * @throws IOException if this instance is closed.
-     */
-    static void checkOpen(final boolean isOpen) throws IOException {
-        if (!isOpen) {
-            throw new IOException("The stream is closed.");
-        }
-    }
-
     /**
      * Whether {@link #close()} completed successfully.
      */
@@ -50,7 +38,7 @@ static void checkOpen(final boolean isOpen) throws IOException {
      * @throws IOException if this instance is closed.
      */
     void checkOpen() throws IOException {
-        checkOpen(!isClosed());
+        Input.checkOpen(!isClosed());
     }
 
     @Override

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

@@ -243,7 +243,7 @@ public synchronized int read(final byte[] b, final int offset, int len) throws I
      * @throws IOException if an I/O error occurs.
      */
     private boolean refill() throws IOException {
-        AbstractInputStream.checkOpen(fileChannel.isOpen());
+        Input.checkOpen(fileChannel.isOpen());
         if (!byteBuffer.hasRemaining()) {
             byteBuffer.clear();
             int nRead = 0;

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

@@ -0,0 +1,39 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.commons.io.input;
+
+import java.io.IOException;
+
+/**
+ * Package-wide internals for input.
+ */
+class Input {
+
+    /**
+     * Throws an IOException on false input.
+     *
+     * @param isOpen whether an input is open or not.
+     * @throws IOException if {@code isOpen} is false indicating an input is closed.
+     */
+    static void checkOpen(final boolean isOpen) throws IOException {
+        if (!isOpen) {
+            throw new IOException("Closed");
+        }
+    }
+
+}

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

@@ -149,7 +149,7 @@ protected void beforeRead(final int n) throws IOException {
      * @throws IOException if this instance is closed.
      */
     void checkOpen() throws IOException {
-        AbstractInputStream.checkOpen(!isClosed());
+        Input.checkOpen(!isClosed());
     }
 
     /**

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

@@ -91,8 +91,7 @@ public class UnsynchronizedBufferedReader extends UnsynchronizedReader {
      * @param in the Reader that is buffered.
      */
     public UnsynchronizedBufferedReader(final Reader in) {
-        this.in = in;
-        buf = new char[IOUtils.DEFAULT_BUFFER_SIZE];
+        this(in, IOUtils.DEFAULT_BUFFER_SIZE);
     }
 
     /**
@@ -110,12 +109,6 @@ public UnsynchronizedBufferedReader(final Reader in, final int size) {
         buf = new char[size];
     }
 
-    private void checkClosed() throws IOException {
-        if (isClosed()) {
-            throw new IOException("Closed");
-        }
-    }
-
     /**
      * Peeks at the next input character, refilling the buffer if necessary. If this character is a newline character ("\n"), it is discarded.
      */
@@ -136,6 +129,7 @@ public void close() throws IOException {
         if (!isClosed()) {
             in.close();
             buf = null;
+            super.close();
         }
     }
 
@@ -183,15 +177,6 @@ private int fillBuf() throws IOException {
         return count;
     }
 
-    /**
-     * Tests whether or not this reader is closed.
-     *
-     * @return {@code true} if this reader is closed, {@code false} otherwise.
-     */
-    private boolean isClosed() {
-        return buf == null;
-    }
-
     /**
      * Sets a mark position in this reader. The parameter {@code markLimit} indicates how many characters can be read before the mark is invalidated. Calling
      * {@link #reset()} will reposition the reader back to the marked position if {@code markLimit} has not been surpassed.
@@ -207,7 +192,7 @@ public void mark(final int markLimit) throws IOException {
         if (markLimit < 0) {
             throw new IllegalArgumentException();
         }
-        checkClosed();
+        checkOpen();
         this.markLimit = markLimit;
         mark = pos;
     }
@@ -234,7 +219,7 @@ public boolean markSupported() {
      */
     @Override
     public int read() throws IOException {
-        checkClosed();
+        checkOpen();
         /* Are there buffered characters available? */
         if (pos < end || fillBuf() != EOF) {
             return buf[pos++];
@@ -257,7 +242,7 @@ public int read() throws IOException {
      */
     @Override
     public int read(final char[] buffer, int offset, final int length) throws IOException {
-        checkClosed();
+        checkOpen();
         if (offset < 0 || offset > buffer.length - length || length < 0) {
             throw new IndexOutOfBoundsException();
         }
@@ -317,7 +302,7 @@ public int read(final char[] buffer, int offset, final int length) throws IOExce
      * @throws IOException if this reader is closed or some other I/O error occurs.
      */
     public String readLine() throws IOException {
-        checkClosed();
+        checkOpen();
         /* has the underlying stream been exhausted? */
         if (pos == end && fillBuf() == EOF) {
             return null;
@@ -331,7 +316,8 @@ public String readLine() throws IOException {
                 final String res = new String(buf, pos, charPos - pos);
                 pos = charPos + 1;
                 return res;
-            } else if (ch == CR) {
+            }
+            if (ch == CR) {
                 final String res = new String(buf, pos, charPos - pos);
                 pos = charPos + 1;
                 if ((pos < end || fillBuf() != EOF) && buf[pos] == LF) {
@@ -360,11 +346,7 @@ public String readLine() throws IOException {
             }
             for (int charPos = pos; charPos < end; charPos++) {
                 final char c = buf[charPos];
-                if (eol == NUL) {
-                    if (c == LF || c == CR) {
-                        eol = c;
-                    }
-                } else {
+                if (eol != NUL) {
                     if (eol == CR && c == LF) {
                         if (charPos > pos) {
                             result.append(buf, pos, charPos - pos - 1);
@@ -378,6 +360,9 @@ public String readLine() throws IOException {
                     }
                     return result.toString();
                 }
+                if (c == LF || c == CR) {
+                    eol = c;
+                }
             }
             if (eol == NUL) {
                 result.append(buf, pos, end - pos);
@@ -398,7 +383,7 @@ public String readLine() throws IOException {
      */
     @Override
     public boolean ready() throws IOException {
-        checkClosed();
+        checkOpen();
         return end - pos > 0 || in.ready();
     }
 
@@ -411,7 +396,7 @@ public boolean ready() throws IOException {
      */
     @Override
     public void reset() throws IOException {
-        checkClosed();
+        checkOpen();
         if (mark == -1) {
             throw new IOException("mark == -1");
         }
@@ -435,7 +420,7 @@ public long skip(final long amount) throws IOException {
         if (amount < 0) {
             throw new IllegalArgumentException();
         }
-        checkClosed();
+        checkOpen();
         if (amount < 1) {
             return 0;
         }

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

@@ -36,11 +36,48 @@ public abstract class UnsynchronizedReader extends Reader {
      */
     private static final int MAX_SKIP_BUFFER_SIZE = IOUtils.DEFAULT_BUFFER_SIZE;
 
+    /**
+     * Whether {@link #close()} completed successfully.
+     */
+    private boolean closed;
+
     /**
      * The skip buffer, defaults to null until allocated in {@link UnsynchronizedReader#skip(long)}.
      */
     private char skipBuffer[];
 
+    /**
+     * Checks if this instance is closed and throws an IOException if so.
+     *
+     * @throws IOException if this instance is closed.
+     */
+    void checkOpen() throws IOException {
+        Input.checkOpen(!isClosed());
+    }
+
+    @Override
+    public void close() throws IOException {
+        closed = true;
+    }
+
+    /**
+     * Tests whether this instance is closed; if {@link #close()} completed successfully.
+     *
+     * @return whether this instance is closed.
+     */
+    public boolean isClosed() {
+        return closed;
+    }
+
+    /**
+     * Sets whether this instance is closed.
+     *
+     * @param closed whether this instance is closed.
+     */
+    public void setClosed(final boolean closed) {
+        this.closed = closed;
+    }
+
     /**
      * Skips characters by reading from this instance.
      *