8080835: Add blocking bulk read to sun.misc.IOUtils

Reviewed-by: mbalao

src/share/classes/sun/misc/IOUtils.java

@@ -32,10 +32,22 @@ package sun.misc;
 import java.io.EOFException;
 import java.io.IOException;
 import java.io.InputStream;
+
 import java.util.Arrays;
+import java.util.Objects;
 
 public class IOUtils {
 
+    private static final int DEFAULT_BUFFER_SIZE = 8192;
+
+    /**
+     * The maximum size of array to allocate.
+     * Some VMs reserve some header words in an array.
+     * Attempts to allocate larger arrays may result in
+     * OutOfMemoryError: Requested array size exceeds VM limit
+     */
+    private static final int MAX_BUFFER_SIZE = Integer.MAX_VALUE - 8;
+
     /**
      * Read up to {@code length} of bytes from {@code in}
      * until EOF is detected.
@@ -95,4 +107,121 @@ public class IOUtils {
         }
         return readFully(is, length, true);
     }
+
+    /**
+     * Reads all remaining bytes from the input stream. This method blocks until
+     * all remaining bytes have been read and end of stream is detected, or an
+     * exception is thrown. This method does not close the input stream.
+     *
+     * <p> When this stream reaches end of stream, further invocations of this
+     * method will return an empty byte array.
+     *
+     * <p> Note that this method is intended for simple cases where it is
+     * convenient to read all bytes into a byte array. It is not intended for
+     * reading input streams with large amounts of data.
+     *
+     * <p> The behavior for the case where the input stream is <i>asynchronously
+     * closed</i>, or the thread interrupted during the read, is highly input
+     * stream specific, and therefore not specified.
+     *
+     * <p> If an I/O error occurs reading from the input stream, then it may do
+     * so after some, but not all, bytes have been read. Consequently the input
+     * stream may not be at end of stream and may be in an inconsistent state.
+     * It is strongly recommended that the stream be promptly closed if an I/O
+     * error occurs.
+     *
+     * @param is input stream, must not be null
+     * @return a byte array containing the bytes read from this input stream
+     * @throws IOException if an I/O error occurs
+     * @throws OutOfMemoryError if an array of the required size cannot be
+     *         allocated. For example, if an array larger than {@code 2GB} would
+     *         be required to store the bytes.
+     *
+     * @since 1.9
+     */
+    public static byte[] readAllBytes(InputStream is) throws IOException {
+        byte[] buf = new byte[DEFAULT_BUFFER_SIZE];
+        int capacity = buf.length;
+        int nread = 0;
+        int n;
+        for (;;) {
+            // read to EOF which may read more or less than initial buffer size
+            while ((n = is.read(buf, nread, capacity - nread)) > 0)
+                nread += n;
+
+            // if the last call to read returned -1, then we're done
+            if (n < 0)
+                break;
+
+            // need to allocate a larger buffer
+            if (capacity <= MAX_BUFFER_SIZE - capacity) {
+                capacity = capacity << 1;
+            } else {
+                if (capacity == MAX_BUFFER_SIZE)
+                    throw new OutOfMemoryError("Required array size too large");
+                capacity = MAX_BUFFER_SIZE;
+            }
+            buf = Arrays.copyOf(buf, capacity);
+        }
+        return (capacity == nread) ? buf : Arrays.copyOf(buf, nread);
+    }
+
+    /**
+     * Reads the requested number of bytes from the input stream into the given
+     * byte array. This method blocks until {@code len} bytes of input data have
+     * been read, end of stream is detected, or an exception is thrown. The
+     * number of bytes actually read, possibly zero, is returned. This method
+     * does not close the input stream.
+     *
+     * <p> In the case where end of stream is reached before {@code len} bytes
+     * have been read, then the actual number of bytes read will be returned.
+     * When this stream reaches end of stream, further invocations of this
+     * method will return zero.
+     *
+     * <p> If {@code len} is zero, then no bytes are read and {@code 0} is
+     * returned; otherwise, there is an attempt to read up to {@code len} bytes.
+     *
+     * <p> The first byte read is stored into element {@code b[off]}, the next
+     * one in to {@code b[off+1]}, and so on. The number of bytes read is, at
+     * most, equal to {@code len}. Let <i>k</i> be the number of bytes actually
+     * read; these bytes will be stored in elements {@code b[off]} through
+     * {@code b[off+}<i>k</i>{@code -1]}, leaving elements {@code b[off+}<i>k</i>
+     * {@code ]} through {@code b[off+len-1]} unaffected.
+     *
+     * <p> The behavior for the case where the input stream is <i>asynchronously
+     * closed</i>, or the thread interrupted during the read, is highly input
+     * stream specific, and therefore not specified.
+     *
+     * <p> If an I/O error occurs reading from the input stream, then it may do
+     * so after some, but not all, bytes of {@code b} have been updated with
+     * data from the input stream. Consequently the input stream and {@code b}
+     * may be in an inconsistent state. It is strongly recommended that the
+     * stream be promptly closed if an I/O error occurs.
+     *
+     * @param  is input stream, must not be null
+     * @param  b the byte array into which the data is read
+     * @param  off the start offset in {@code b} at which the data is written
+     * @param  len the maximum number of bytes to read
+     * @return the actual number of bytes read into the buffer
+     * @throws IOException if an I/O error occurs
+     * @throws NullPointerException if {@code b} is {@code null}
+     * @throws IndexOutOfBoundsException If {@code off} is negative, {@code len}
+     *         is negative, or {@code len} is greater than {@code b.length - off}
+     *
+     * @since 1.9
+     */
+    public static int readNBytes(InputStream is, byte[] b, int off, int len) throws IOException {
+        Objects.requireNonNull(b);
+        if (off < 0 || len < 0 || len > b.length - off)
+            throw new IndexOutOfBoundsException();
+        int n = 0;
+        while (n < len) {
+            int count = is.read(b, off + n, len - n);
+            if (count < 0)
+                break;
+            n += count;
+        }
+        return n;
+    }
+
 }

test/sun/misc/IOUtils/ReadAllBytes.java

+/*
+ * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+import java.io.ByteArrayInputStream;
+import java.io.FilterInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.Arrays;
+import java.util.Random;
+
+import jdk.testlibrary.RandomFactory;
+
+import sun.misc.IOUtils;
+
+/*
+ * @test
+ * @bug 8080835
+ * @library /lib/testlibrary
+ * @build jdk.testlibrary.*
+ * @run main ReadAllBytes
+ * @summary Basic test for IOUtils.readAllBytes
+ * @key randomness
+ */
+
+public class ReadAllBytes {
+
+    private static Random generator = RandomFactory.getRandom();
+
+    public static void main(String[] args) throws IOException {
+        test(new byte[]{});
+        test(new byte[]{1, 2, 3});
+        test(createRandomBytes(1024));
+        test(createRandomBytes((1 << 13) - 1));
+        test(createRandomBytes((1 << 13)));
+        test(createRandomBytes((1 << 13) + 1));
+        test(createRandomBytes((1 << 15) - 1));
+        test(createRandomBytes((1 << 15)));
+        test(createRandomBytes((1 << 15) + 1));
+        test(createRandomBytes((1 << 17) - 1));
+        test(createRandomBytes((1 << 17)));
+        test(createRandomBytes((1 << 17) + 1));
+    }
+
+    static void test(byte[] expectedBytes) throws IOException {
+        int expectedLength = expectedBytes.length;
+        WrapperInputStream in = new WrapperInputStream(new ByteArrayInputStream(expectedBytes));
+        byte[] readBytes = IOUtils.readAllBytes(in);
+
+        int x;
+        byte[] tmp = new byte[10];
+        check((x = in.read()) == -1,
+              "Expected end of stream from read(), got " + x);
+        check((x = in.read(tmp)) == -1,
+              "Expected end of stream from read(byte[]), got " + x);
+        check((x = in.read(tmp, 0, tmp.length)) == -1,
+              "Expected end of stream from read(byte[], int, int), got " + x);
+        check(IOUtils.readAllBytes(in).length == 0,
+              "Expected readAllBytes to return empty byte array");
+        check(expectedLength == readBytes.length,
+              "Expected length " + expectedLength + ", got " + readBytes.length);
+        check(Arrays.equals(expectedBytes, readBytes),
+              "Expected[" + expectedBytes + "], got:[" + readBytes + "]");
+        check(!in.isClosed(), "Stream unexpectedly closed");
+    }
+
+    static byte[] createRandomBytes(int size) {
+        byte[] bytes = new byte[size];
+        generator.nextBytes(bytes);
+        return bytes;
+    }
+
+    static void check(boolean cond, Object ... failedArgs) {
+        if (cond)
+            return;
+        StringBuilder sb = new StringBuilder();
+        for (Object o : failedArgs)
+            sb.append(o);
+        throw new RuntimeException(sb.toString());
+    }
+
+    static class WrapperInputStream extends FilterInputStream {
+        private boolean closed;
+        WrapperInputStream(InputStream in) { super(in); }
+        @Override public void close() throws IOException { closed = true; in.close(); }
+        boolean isClosed() { return closed; }
+    }
+}

test/sun/misc/IOUtils/ReadNBytes.java

+/*
+ * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+import java.io.ByteArrayInputStream;
+import java.io.FilterInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.Arrays;
+import java.util.Random;
+import jdk.testlibrary.RandomFactory;
+
+import sun.misc.IOUtils;
+
+/*
+ * @test
+ * @bug 8080835
+ * @library /lib/testlibrary
+ * @build jdk.testlibrary.*
+ * @run main ReadNBytes
+ * @summary Basic test for IOUtils.readNBytes
+ * @key randomness
+ */
+
+public class ReadNBytes {
+
+    private static Random generator = RandomFactory.getRandom();
+
+    public static void main(String[] args) throws IOException {
+        test(new byte[]{1, 2, 3});
+        test(createRandomBytes(1024));
+        test(createRandomBytes((1 << 13) - 1));
+        test(createRandomBytes((1 << 13)));
+        test(createRandomBytes((1 << 13) + 1));
+        test(createRandomBytes((1 << 15) - 1));
+        test(createRandomBytes((1 << 15)));
+        test(createRandomBytes((1 << 15) + 1));
+        test(createRandomBytes((1 << 17) - 1));
+        test(createRandomBytes((1 << 17)));
+        test(createRandomBytes((1 << 17) + 1));
+    }
+
+    static void test(byte[] inputBytes) throws IOException {
+        int length = inputBytes.length;
+        WrapperInputStream in = new WrapperInputStream(new ByteArrayInputStream(inputBytes));
+        byte[] readBytes = new byte[(length / 2) + 1];
+        int nread = IOUtils.readNBytes(in, readBytes, 0, readBytes.length);
+
+        int x;
+        byte[] tmp;
+        check(nread == readBytes.length,
+              "Expected number of bytes read: " + readBytes.length + ", got: " + nread);
+        check(Arrays.equals((tmp = Arrays.copyOf(inputBytes, nread)), readBytes),
+              "Expected[" + tmp + "], got:[" + readBytes + "]");
+        check(!in.isClosed(), "Stream unexpectedly closed");
+
+        // Read again
+        nread = IOUtils.readNBytes(in, readBytes, 0, readBytes.length);
+
+        check(nread == length - readBytes.length,
+              "Expected number of bytes read: " + (length - readBytes.length) + ", got: " + nread);
+        check(Arrays.equals((tmp = Arrays.copyOfRange(inputBytes, readBytes.length, length)),
+                            Arrays.copyOf(readBytes, nread)),
+              "Expected[" + tmp + "], got:[" + readBytes + "]");
+        // Expect end of stream
+        check((x = in.read()) == -1,
+              "Expected end of stream from read(), got " + x);
+        check((x = in.read(tmp)) == -1,
+              "Expected end of stream from read(byte[]), got " + x);
+        check((x = in.read(tmp, 0, tmp.length)) == -1,
+              "Expected end of stream from read(byte[], int, int), got " + x);
+        check((x = IOUtils.readNBytes(in, tmp, 0, tmp.length)) == 0,
+              "Expected end of stream, 0, from readNBytes(byte[], int, int), got " + x);
+        check(!in.isClosed(), "Stream unexpectedly closed");
+    }
+
+    static byte[] createRandomBytes(int size) {
+        byte[] bytes = new byte[size];
+        generator.nextBytes(bytes);
+        return bytes;
+    }
+
+    static void check(boolean cond, Object ... failedArgs) {
+        if (cond)
+            return;
+        StringBuilder sb = new StringBuilder();
+        for (Object o : failedArgs)
+            sb.append(o);
+        throw new RuntimeException(sb.toString());
+    }
+
+
+    static class WrapperInputStream extends FilterInputStream {
+        private boolean closed;
+        WrapperInputStream(InputStream in) { super(in); }
+        @Override public void close() throws IOException { closed = true; in.close(); }
+        boolean isClosed() { return closed; }
+    }
+}