Add and reuse IOConsumer.forEach(*) and forEachIndexed(*).

Use forEach and streams.

Author: Gary Gregory

src/changes/changes.xml

@@ -357,7 +357,7 @@ The <action> type attribute can be add,update,fix,remove.
         Add IOBiConsumer.
       </action>
       <action dev="ggregory" type="add" due-to="Gary Gregory">
-        Add and reuse IOConsumer.forEach(T[], IOConsumer) and forEachIndexed(Stream, IOConsumer).
+        Add and reuse IOConsumer.forEach(*) and forEachIndexed(*).
       </action>
       <action dev="ggregory" type="add" due-to="Gary Gregory">
         Add CharsetEncoders.

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

@@ -23,12 +23,12 @@
 import java.io.OutputStream;
 import java.nio.charset.Charset;
 import java.time.Duration;
-import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
 import java.util.Locale;
 import java.util.Objects;
 import java.util.StringTokenizer;
+import java.util.stream.Collectors;
 
 /**
  * General File System utilities.
@@ -487,7 +487,7 @@ List<String> performCommand(final String[] cmdAttribs, final int max, final Dura
         // however, it's still not perfect as the JDK support is so poor
         // (see commons-exec or Ant for a better multithreaded multi-os solution)
 
-        final List<String> lines = new ArrayList<>(20);
+        final List<String> lines;
         Process proc = null;
         InputStream in = null;
         OutputStream out = null;
@@ -503,28 +503,20 @@ List<String> performCommand(final String[] cmdAttribs, final int max, final Dura
             err = proc.getErrorStream();
             // default charset is most likely appropriate here
             inr = new BufferedReader(new InputStreamReader(in, Charset.defaultCharset()));
-            String line = inr.readLine();
-            while (line != null && lines.size() < max) {
-                line = line.toLowerCase(Locale.ENGLISH).trim();
-                lines.add(line);
-                line = inr.readLine();
-            }
+
+            lines = inr.lines().limit(max).map(line -> line.toLowerCase(Locale.ENGLISH).trim()).collect(Collectors.toList());
 
             proc.waitFor();
 
             ThreadMonitor.stop(monitor);
 
             if (proc.exitValue() != 0) {
                 // OS command problem, throw exception
-                throw new IOException(
-                        "Command line returned OS error code '" + proc.exitValue() +
-                        "' for command " + Arrays.asList(cmdAttribs));
+                throw new IOException("Command line returned OS error code '" + proc.exitValue() + "' for command " + Arrays.asList(cmdAttribs));
             }
             if (lines.isEmpty()) {
                 // unknown problem, throw exception
-                throw new IOException(
-                        "Command line did not return any info " +
-                        "for command " + Arrays.asList(cmdAttribs));
+                throw new IOException("Command line did not return any info " + "for command " + Arrays.asList(cmdAttribs));
             }
 
             inr.close();

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

@@ -25,6 +25,7 @@
 import java.util.List;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
+import java.util.stream.Stream;
 
 /**
  * General file name and file path manipulation utilities.
@@ -1054,12 +1055,7 @@ public static boolean isExtension(final String fileName, final String... extensi
             return indexOfExtension(fileName) == NOT_FOUND;
         }
         final String fileExt = getExtension(fileName);
-        for (final String extension : extensions) {
-            if (fileExt.equals(extension)) {
-                return true;
-            }
-        }
-        return false;
+        return Stream.of(extensions).anyMatch(fileExt::equals);
     }
 
     /**

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

@@ -31,6 +31,7 @@
 import java.io.OutputStream;
 import java.io.OutputStreamWriter;
 import java.io.Reader;
+import java.io.UncheckedIOException;
 import java.io.Writer;
 import java.net.HttpURLConnection;
 import java.net.ServerSocket;
@@ -45,12 +46,13 @@
 import java.nio.channels.Selector;
 import java.nio.charset.Charset;
 import java.nio.file.Files;
-import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
+import java.util.Iterator;
 import java.util.List;
 import java.util.Objects;
 import java.util.function.Consumer;
+import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
 import org.apache.commons.io.function.IOConsumer;
@@ -428,6 +430,15 @@ public static void close(final URLConnection conn) {
         }
     }
 
+    /**
+     * Avoids the need to type cast.
+     *
+     * @param closeable the object to close, may be null
+     */
+    private static void closeQ(final Closeable closeable) {
+        closeQuietly(closeable, null);
+    }
+
     /**
      * Closes a {@link Closeable} unconditionally.
      *
@@ -473,15 +484,6 @@ public static void closeQuietly(final Closeable closeable) {
         closeQuietly(closeable, null);
     }
 
-    /**
-     * Avoids the need to type cast.
-     *
-     * @param closeable the object to close, may be null
-     */
-    private static void closeQ(final Closeable closeable) {
-        closeQuietly(closeable, null);
-    }
-
     /**
      * Closes a {@link Closeable} unconditionally.
      * <p>
@@ -602,22 +604,6 @@ public static void closeQuietly(final Iterable<Closeable> closeables) {
         }
     }
 
-    /**
-     * Closes a stream of {@link Closeable} unconditionally.
-     * <p>
-     * Equivalent calling {@link Closeable#close()} on each element, except any exceptions will be ignored.
-     * </p>
-     *
-     * @param closeables the objects to close, may be null or already closed
-     * @see #closeQuietly(Closeable)
-     * @since 2.12.0
-     */
-    public static void closeQuietly(final Stream<Closeable> closeables) {
-        if (closeables != null) {
-            closeables.forEach(IOUtils::closeQuietly);
-        }
-    }
-
     /**
      * Closes an {@link OutputStream} unconditionally.
      * <p>
@@ -784,6 +770,22 @@ public static void closeQuietly(final Socket socket) {
         closeQ(socket);
     }
 
+    /**
+     * Closes a stream of {@link Closeable} unconditionally.
+     * <p>
+     * Equivalent calling {@link Closeable#close()} on each element, except any exceptions will be ignored.
+     * </p>
+     *
+     * @param closeables the objects to close, may be null or already closed
+     * @see #closeQuietly(Closeable)
+     * @since 2.12.0
+     */
+    public static void closeQuietly(final Stream<Closeable> closeables) {
+        if (closeables != null) {
+            closeables.forEach(IOUtils::closeQuietly);
+        }
+    }
+
     /**
      * Closes an {@link Writer} unconditionally.
      * <p>
@@ -895,6 +897,19 @@ public static boolean contentEquals(final InputStream input1, final InputStream
         }
     }
 
+    // TODO Consider making public
+    private static boolean contentEquals(final Iterator<?> iterator1, final Iterator<?> iterator2) {
+        while (iterator1.hasNext()) {
+            if (!iterator2.hasNext()) {
+                return false;
+            }
+            if (!Objects.equals(iterator1.next(), iterator2.next())) {
+                return false;
+            }
+        }
+        return !iterator2.hasNext();
+    }
+
     /**
      * Compares the contents of two Readers to determine if they are equal or not.
      * <p>
@@ -953,6 +968,28 @@ public static boolean contentEquals(final Reader input1, final Reader input2) th
         }
     }
 
+    // TODO Consider making public
+    private static boolean contentEquals(final Stream<?> stream1, final Stream<?> stream2) {
+        if (stream1 == stream2) {
+            return true;
+        }
+        if (stream1 == null || stream2 == null) {
+            return false;
+        }
+        return contentEquals(stream1.iterator(), stream2.iterator());
+    }
+
+    // TODO Consider making public
+    private static boolean contentEqualsIgnoreEOL(final BufferedReader reader1, final BufferedReader reader2) {
+        if (reader1 == reader2) {
+            return true;
+        }
+        if (reader1 == null || reader2 == null) {
+            return false;
+        }
+        return contentEquals(reader1.lines(), reader2.lines());
+    }
+
     /**
      * Compares the contents of two Readers to determine if they are equal or
      * not, ignoring EOL characters.
@@ -965,28 +1002,18 @@ public static boolean contentEquals(final Reader input1, final Reader input2) th
      * @param reader2 the second reader
      * @return true if the content of the readers are equal (ignoring EOL differences),  false otherwise
      * @throws NullPointerException if either input is null
-     * @throws IOException          if an I/O error occurs
+     * @throws UncheckedIOException if an I/O error occurs
      * @since 2.2
      */
     @SuppressWarnings("resource")
-    public static boolean contentEqualsIgnoreEOL(final Reader reader1, final Reader reader2)
-            throws IOException {
+    public static boolean contentEqualsIgnoreEOL(final Reader reader1, final Reader reader2) throws UncheckedIOException {
         if (reader1 == reader2) {
             return true;
         }
-        if (reader1 == null ^ reader2 == null) {
+        if (reader1 == null || reader2 == null) {
             return false;
         }
-        final BufferedReader br1 = toBufferedReader(reader1);
-        final BufferedReader br2 = toBufferedReader(reader2);
-
-        String line1 = br1.readLine();
-        String line2 = br2.readLine();
-        while (line1 != null && line1.equals(line2)) {
-            line1 = br1.readLine();
-            line2 = br2.readLine();
-        }
-        return Objects.equals(line1, line2);
+        return contentEqualsIgnoreEOL(toBufferedReader(reader1), toBufferedReader(reader2));
     }
 
     /**
@@ -2042,12 +2069,12 @@ public static void readFully(final Reader reader, final char[] buffer, final int
      * @param input the {@link InputStream} to read from, not null
      * @return the list of Strings, never null
      * @throws NullPointerException if the input is null
-     * @throws IOException          if an I/O error occurs
+     * @throws UncheckedIOException if an I/O error occurs
      * @since 1.1
      * @deprecated 2.5 use {@link #readLines(InputStream, Charset)} instead
      */
     @Deprecated
-    public static List<String> readLines(final InputStream input) throws IOException {
+    public static List<String> readLines(final InputStream input) throws UncheckedIOException {
         return readLines(input, Charset.defaultCharset());
     }
 
@@ -2063,12 +2090,11 @@ public static List<String> readLines(final InputStream input) throws IOException
      * @param charset the charset to use, null means platform default
      * @return the list of Strings, never null
      * @throws NullPointerException if the input is null
-     * @throws IOException          if an I/O error occurs
+     * @throws UncheckedIOException if an I/O error occurs
      * @since 2.3
      */
-    public static List<String> readLines(final InputStream input, final Charset charset) throws IOException {
-        final InputStreamReader reader = new InputStreamReader(input, Charsets.toCharset(charset));
-        return readLines(reader);
+    public static List<String> readLines(final InputStream input, final Charset charset) throws UncheckedIOException {
+        return readLines(new InputStreamReader(input, Charsets.toCharset(charset)));
     }
 
     /**
@@ -2087,13 +2113,13 @@ public static List<String> readLines(final InputStream input, final Charset char
      * @param charsetName the name of the requested charset, null means platform default
      * @return the list of Strings, never null
      * @throws NullPointerException                         if the input is null
-     * @throws IOException                                  if an I/O error occurs
+     * @throws UncheckedIOException                         if an I/O error occurs
      * @throws java.nio.charset.UnsupportedCharsetException thrown instead of {@link java.io
      *                                                      .UnsupportedEncodingException} in version 2.2 if the
      *                                                      encoding is not supported.
      * @since 1.1
      */
-    public static List<String> readLines(final InputStream input, final String charsetName) throws IOException {
+    public static List<String> readLines(final InputStream input, final String charsetName) throws UncheckedIOException {
         return readLines(input, Charsets.toCharset(charsetName));
     }
 
@@ -2108,18 +2134,12 @@ public static List<String> readLines(final InputStream input, final String chars
      * @param reader the {@link Reader} to read from, not null
      * @return the list of Strings, never null
      * @throws NullPointerException if the input is null
-     * @throws IOException          if an I/O error occurs
+     * @throws UncheckedIOException if an I/O error occurs
      * @since 1.1
      */
     @SuppressWarnings("resource") // reader wraps input and is the responsibility of the caller.
-    public static List<String> readLines(final Reader reader) throws IOException {
-        final BufferedReader bufReader = toBufferedReader(reader);
-        final List<String> list = new ArrayList<>();
-        String line;
-        while ((line = bufReader.readLine()) != null) {
-            list.add(line);
-        }
-        return list;
+    public static List<String> readLines(final Reader reader) throws UncheckedIOException {
+        return toBufferedReader(reader).lines().collect(Collectors.toList());
     }
 
     /**

src/main/java/org/apache/commons/io/file/PathUtils.java

@@ -820,7 +820,7 @@ public static DosFileAttributeView getDosFileAttributeView(final Path path, fina
      * where {@link File#lastModified()} looses milliseconds and always ends in 000. This bug is in OpenJDK 8 and 9, and
      * fixed in 11.
      * </p>
-     * 
+     *
      * @param file the file to query.
      * @return the file's last modified time.
      * @throws IOException Thrown if an I/O error occurs.

src/main/java/org/apache/commons/io/file/StandardDeleteOption.java

@@ -17,6 +17,8 @@
 
 package org.apache.commons.io.file;
 
+import java.util.stream.Stream;
+
 import org.apache.commons.io.IOUtils;
 
 /**
@@ -43,12 +45,7 @@ public static boolean overrideReadOnly(final DeleteOption[] options) {
         if (IOUtils.length(options) == 0) {
             return false;
         }
-        for (final DeleteOption deleteOption : options) {
-            if (deleteOption == StandardDeleteOption.OVERRIDE_READ_ONLY) {
-                return true;
-            }
-        }
-        return false;
+        return Stream.of(options).anyMatch(e -> StandardDeleteOption.OVERRIDE_READ_ONLY == e);
     }
 
 }

src/main/java/org/apache/commons/io/filefilter/AndFileFilter.java

@@ -25,6 +25,7 @@
 import java.util.Collections;
 import java.util.List;
 import java.util.Objects;
+import java.util.stream.Stream;
 
 /**
  * A {@link java.io.FileFilter} providing conditional AND logic across a list of
@@ -148,9 +149,7 @@ public void addFileFilter(final IOFileFilter fileFilter) {
      * @since 2.9.0
      */
     public void addFileFilter(final IOFileFilter... fileFilters) {
-        for (final IOFileFilter fileFilter : Objects.requireNonNull(fileFilters, "fileFilters")) {
-            addFileFilter(fileFilter);
-        }
+        Stream.of(Objects.requireNonNull(fileFilters, "fileFilters")).forEach(this::addFileFilter);
     }
 
     /**