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/*
 * Copyright (C) 2007 The Guava Authors
 *
 * Licensed 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 com.google.common.io;

import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.base.Preconditions.checkNotNull;
import static com.google.common.base.Preconditions.checkPositionIndex;
import com.google.common.annotations.Beta;
import com.google.common.base.Function;
import com.google.common.collect.Iterables;
import com.google.common.hash.HashCode;
import com.google.common.hash.HashFunction;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.DataInput;
import java.io.DataInputStream;
import java.io.DataOutput;
import java.io.DataOutputStream;
import java.io.EOFException;
import java.io.FilterInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.nio.ByteBuffer;
import java.nio.channels.ReadableByteChannel;
import java.nio.channels.WritableByteChannel;
import java.util.Arrays;

/**
 *  Provides utility methods for working with byte arrays and I/O streams.
 *
 *  @author Chris Nokleberg
 *  @author Colin Decker
 *  @since 1.0
 *
 * @deprecated The Google Guava Core Libraries are deprecated and will not be part of the AEM SDK after April 2023
 */
@Beta
@Deprecated(since = "2022-12-01")
public final class ByteStreams {

    // 4K
    private static final int BUF_SIZE = 0x1000;

    private ByteStreams() {
    }

    /**
     * Returns a factory that will supply instances of
     * {@link ByteArrayInputStream} that read from the given byte array.
     *
     * @param b the input buffer
     * @return the factory
     */
    public static InputSupplier newInputStreamSupplier(byte[] b) {
        return asInputSupplier(ByteSource.wrap(b));
    }

    /**
     * Returns a factory that will supply instances of
     * {@link ByteArrayInputStream} that read from the given byte array.
     *
     * @param b the input buffer
     * @param off the offset in the buffer of the first byte to read
     * @param len the maximum number of bytes to read from the buffer
     * @return the factory
     */
    public static InputSupplier newInputStreamSupplier(final byte[] b, final int off, final int len) {
        return asInputSupplier(ByteSource.wrap(b).slice(off, len));
    }

    /**
     * Returns a new {@link ByteSource} that reads bytes from the given byte array.
     *
     * @since 14.0
     * @deprecated Use {@link ByteSource#wrap(byte[])} instead. This method is
     *     scheduled to be removed in Guava 16.0.
     */
    @Deprecated
    public static ByteSource asByteSource(byte[] b) {
        return ByteSource.wrap(b);
    }

    /**
     * Writes a byte array to an output stream from the given supplier.
     *
     * @param from the bytes to write
     * @param to the output supplier
     * @throws IOException if an I/O error occurs
     */
    public static void write(byte[] from, OutputSupplier to) throws IOException {
        asByteSink(to).write(from);
    }

    /**
     * Opens input and output streams from the given suppliers, copies all
     * bytes from the input to the output, and closes the streams.
     *
     * @param from the input factory
     * @param to the output factory
     * @return the number of bytes copied
     * @throws IOException if an I/O error occurs
     */
    public static long copy(InputSupplier from, OutputSupplier to) throws IOException {
        return asByteSource(from).copyTo(asByteSink(to));
    }

    /**
     * Opens an input stream from the supplier, copies all bytes from the
     * input to the output, and closes the input stream. Does not close
     * or flush the output stream.
     *
     * @param from the input factory
     * @param to the output stream to write to
     * @return the number of bytes copied
     * @throws IOException if an I/O error occurs
     */
    public static long copy(InputSupplier from, OutputStream to) throws IOException {
        return asByteSource(from).copyTo(to);
    }

    /**
     * Opens an output stream from the supplier, copies all bytes from the input
     * to the output, and closes the output stream. Does not close or flush the
     * input stream.
     *
     * @param from the input stream to read from
     * @param to the output factory
     * @return the number of bytes copied
     * @throws IOException if an I/O error occurs
     * @since 10.0
     */
    public static long copy(InputStream from, OutputSupplier to) throws IOException {
        return asByteSink(to).writeFrom(from);
    }

    /**
     * Copies all bytes from the input stream to the output stream.
     * Does not close or flush either stream.
     *
     * @param from the input stream to read from
     * @param to the output stream to write to
     * @return the number of bytes copied
     * @throws IOException if an I/O error occurs
     */
    public static long copy(InputStream from, OutputStream to) throws IOException {
        checkNotNull(from);
        checkNotNull(to);
        byte[] buf = new byte[BUF_SIZE];
        long total = 0;
        while (true) {
            int r = from.read(buf);
            if (r == -1) {
                break;
            }
            to.write(buf, 0, r);
            total += r;
        }
        return total;
    }

    /**
     * Copies all bytes from the readable channel to the writable channel.
     * Does not close or flush either channel.
     *
     * @param from the readable channel to read from
     * @param to the writable channel to write to
     * @return the number of bytes copied
     * @throws IOException if an I/O error occurs
     */
    public static long copy(ReadableByteChannel from, WritableByteChannel to) throws IOException {
        checkNotNull(from);
        checkNotNull(to);
        ByteBuffer buf = ByteBuffer.allocate(BUF_SIZE);
        long total = 0;
        while (from.read(buf) != -1) {
            buf.flip();
            while (buf.hasRemaining()) {
                total += to.write(buf);
            }
            buf.clear();
        }
        return total;
    }

    /**
     * Reads all bytes from an input stream into a byte array.
     * Does not close the stream.
     *
     * @param in the input stream to read from
     * @return a byte array containing all the bytes from the stream
     * @throws IOException if an I/O error occurs
     */
    public static byte[] toByteArray(InputStream in) throws IOException {
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        copy(in, out);
        return out.toByteArray();
    }

    /**
     * Returns the data from a {@link InputStream} factory as a byte array.
     *
     * @param supplier the factory
     * @throws IOException if an I/O error occurs
     */
    public static byte[] toByteArray(InputSupplier supplier) throws IOException {
        return asByteSource(supplier).read();
    }

    /**
     * Returns a new {@link ByteArrayDataInput} instance to read from the {@code
     * bytes} array from the beginning.
     */
    public static ByteArrayDataInput newDataInput(byte[] bytes) {
        return new ByteArrayDataInputStream(bytes);
    }

    /**
     * Returns a new {@link ByteArrayDataInput} instance to read from the {@code
     * bytes} array, starting at the given position.
     *
     * @throws IndexOutOfBoundsException if {@code start} is negative or greater
     *     than the length of the array
     */
    public static ByteArrayDataInput newDataInput(byte[] bytes, int start) {
        checkPositionIndex(start, bytes.length);
        return new ByteArrayDataInputStream(bytes, start);
    }

    // @deprecated The Google Guava Core Libraries are deprecated and will not be part of the AEM SDK after April 2023
    @Deprecated(since = "2022-12-01")
    private static class ByteArrayDataInputStream implements ByteArrayDataInput {

        final DataInput input;

        ByteArrayDataInputStream(byte[] bytes) {
            this.input = new DataInputStream(new ByteArrayInputStream(bytes));
        }

        ByteArrayDataInputStream(byte[] bytes, int start) {
            this.input = new DataInputStream(new ByteArrayInputStream(bytes, start, bytes.length - start));
        }

        @Override
        public void readFully(byte[] b) {
            try {
                input.readFully(b);
            } catch (IOException e) {
                throw new IllegalStateException(e);
            }
        }

        @Override
        public void readFully(byte[] b, int off, int len) {
            try {
                input.readFully(b, off, len);
            } catch (IOException e) {
                throw new IllegalStateException(e);
            }
        }

        @Override
        public int skipBytes(int n) {
            try {
                return input.skipBytes(n);
            } catch (IOException e) {
                throw new IllegalStateException(e);
            }
        }

        @Override
        public boolean readBoolean() {
            try {
                return input.readBoolean();
            } catch (IOException e) {
                throw new IllegalStateException(e);
            }
        }

        @Override
        public byte readByte() {
            try {
                return input.readByte();
            } catch (EOFException e) {
                throw new IllegalStateException(e);
            } catch (IOException impossible) {
                throw new AssertionError(impossible);
            }
        }

        @Override
        public int readUnsignedByte() {
            try {
                return input.readUnsignedByte();
            } catch (IOException e) {
                throw new IllegalStateException(e);
            }
        }

        @Override
        public short readShort() {
            try {
                return input.readShort();
            } catch (IOException e) {
                throw new IllegalStateException(e);
            }
        }

        @Override
        public int readUnsignedShort() {
            try {
                return input.readUnsignedShort();
            } catch (IOException e) {
                throw new IllegalStateException(e);
            }
        }

        @Override
        public char readChar() {
            try {
                return input.readChar();
            } catch (IOException e) {
                throw new IllegalStateException(e);
            }
        }

        @Override
        public int readInt() {
            try {
                return input.readInt();
            } catch (IOException e) {
                throw new IllegalStateException(e);
            }
        }

        @Override
        public long readLong() {
            try {
                return input.readLong();
            } catch (IOException e) {
                throw new IllegalStateException(e);
            }
        }

        @Override
        public float readFloat() {
            try {
                return input.readFloat();
            } catch (IOException e) {
                throw new IllegalStateException(e);
            }
        }

        @Override
        public double readDouble() {
            try {
                return input.readDouble();
            } catch (IOException e) {
                throw new IllegalStateException(e);
            }
        }

        @Override
        public String readLine() {
            try {
                return input.readLine();
            } catch (IOException e) {
                throw new IllegalStateException(e);
            }
        }

        @Override
        public String readUTF() {
            try {
                return input.readUTF();
            } catch (IOException e) {
                throw new IllegalStateException(e);
            }
        }
    }

    /**
     * Returns a new {@link ByteArrayDataOutput} instance with a default size.
     */
    public static ByteArrayDataOutput newDataOutput() {
        return new ByteArrayDataOutputStream();
    }

    /**
     * Returns a new {@link ByteArrayDataOutput} instance sized to hold
     * {@code size} bytes before resizing.
     *
     * @throws IllegalArgumentException if {@code size} is negative
     */
    public static ByteArrayDataOutput newDataOutput(int size) {
        checkArgument(size >= 0, "Invalid size: %s", size);
        return new ByteArrayDataOutputStream(size);
    }

    // @deprecated The Google Guava Core Libraries are deprecated and will not be part of the AEM SDK after April 2023
    // for writeBytes
    @SuppressWarnings("deprecation")
    @Deprecated(since = "2022-12-01")
    private static class ByteArrayDataOutputStream implements ByteArrayDataOutput {

        final DataOutput output;

        final ByteArrayOutputStream byteArrayOutputSteam;

        ByteArrayDataOutputStream() {
            this(new ByteArrayOutputStream());
        }

        ByteArrayDataOutputStream(int size) {
            this(new ByteArrayOutputStream(size));
        }

        ByteArrayDataOutputStream(ByteArrayOutputStream byteArrayOutputSteam) {
            this.byteArrayOutputSteam = byteArrayOutputSteam;
            output = new DataOutputStream(byteArrayOutputSteam);
        }

        @Override
        public void write(int b) {
            try {
                output.write(b);
            } catch (IOException impossible) {
                throw new AssertionError(impossible);
            }
        }

        @Override
        public void write(byte[] b) {
            try {
                output.write(b);
            } catch (IOException impossible) {
                throw new AssertionError(impossible);
            }
        }

        @Override
        public void write(byte[] b, int off, int len) {
            try {
                output.write(b, off, len);
            } catch (IOException impossible) {
                throw new AssertionError(impossible);
            }
        }

        @Override
        public void writeBoolean(boolean v) {
            try {
                output.writeBoolean(v);
            } catch (IOException impossible) {
                throw new AssertionError(impossible);
            }
        }

        @Override
        public void writeByte(int v) {
            try {
                output.writeByte(v);
            } catch (IOException impossible) {
                throw new AssertionError(impossible);
            }
        }

        @Override
        public void writeBytes(String s) {
            try {
                output.writeBytes(s);
            } catch (IOException impossible) {
                throw new AssertionError(impossible);
            }
        }

        @Override
        public void writeChar(int v) {
            try {
                output.writeChar(v);
            } catch (IOException impossible) {
                throw new AssertionError(impossible);
            }
        }

        @Override
        public void writeChars(String s) {
            try {
                output.writeChars(s);
            } catch (IOException impossible) {
                throw new AssertionError(impossible);
            }
        }

        @Override
        public void writeDouble(double v) {
            try {
                output.writeDouble(v);
            } catch (IOException impossible) {
                throw new AssertionError(impossible);
            }
        }

        @Override
        public void writeFloat(float v) {
            try {
                output.writeFloat(v);
            } catch (IOException impossible) {
                throw new AssertionError(impossible);
            }
        }

        @Override
        public void writeInt(int v) {
            try {
                output.writeInt(v);
            } catch (IOException impossible) {
                throw new AssertionError(impossible);
            }
        }

        @Override
        public void writeLong(long v) {
            try {
                output.writeLong(v);
            } catch (IOException impossible) {
                throw new AssertionError(impossible);
            }
        }

        @Override
        public void writeShort(int v) {
            try {
                output.writeShort(v);
            } catch (IOException impossible) {
                throw new AssertionError(impossible);
            }
        }

        @Override
        public void writeUTF(String s) {
            try {
                output.writeUTF(s);
            } catch (IOException impossible) {
                throw new AssertionError(impossible);
            }
        }

        @Override
        public byte[] toByteArray() {
            return byteArrayOutputSteam.toByteArray();
        }
    }

    private static final OutputStream NULL_OUTPUT_STREAM = new OutputStream() {

        /**
         * Discards the specified byte.
         */
        @Override
        public void write(int b) {
        }

        /**
         * Discards the specified byte array.
         */
        @Override
        public void write(byte[] b) {
            checkNotNull(b);
        }

        /**
         * Discards the specified byte array.
         */
        @Override
        public void write(byte[] b, int off, int len) {
            checkNotNull(b);
        }

        @Override
        public String toString() {
            return "ByteStreams.nullOutputStream()";
        }
    };

    /**
     * Returns an {@link OutputStream} that simply discards written bytes.
     *
     * @since 14.0 (since 1.0 as com.google.common.io.NullOutputStream)
     */
    public static OutputStream nullOutputStream() {
        return NULL_OUTPUT_STREAM;
    }

    /**
     * Wraps a {@link InputStream}, limiting the number of bytes which can be
     * read.
     *
     * @param in the input stream to be wrapped
     * @param limit the maximum number of bytes to be read
     * @return a length-limited {@link InputStream}
     * @since 14.0 (since 1.0 as com.google.common.io.LimitInputStream)
     */
    public static InputStream limit(InputStream in, long limit) {
        return new LimitedInputStream(in, limit);
    }

    // @deprecated The Google Guava Core Libraries are deprecated and will not be part of the AEM SDK after April 2023
    @Deprecated(since = "2022-12-01")
    private static final class LimitedInputStream extends FilterInputStream {

        private long left;

        private long mark = -1;

        LimitedInputStream(InputStream in, long limit) {
            super(in);
            checkNotNull(in);
            checkArgument(limit >= 0, "limit must be non-negative");
            left = limit;
        }

        @Override
        public int available() throws IOException {
            return (int) Math.min(in.available(), left);
        }

        // it's okay to mark even if mark isn't supported, as reset won't work
        @Override
        public synchronized void mark(int readLimit) {
            in.mark(readLimit);
            mark = left;
        }

        @Override
        public int read() throws IOException {
            if (left == 0) {
                return -1;
            }
            int result = in.read();
            if (result != -1) {
                --left;
            }
            return result;
        }

        @Override
        public int read(byte[] b, int off, int len) throws IOException {
            if (left == 0) {
                return -1;
            }
            len = (int) Math.min(len, left);
            int result = in.read(b, off, len);
            if (result != -1) {
                left -= result;
            }
            return result;
        }

        @Override
        public synchronized void reset() throws IOException {
            if (!in.markSupported()) {
                throw new IOException("Mark not supported");
            }
            if (mark == -1) {
                throw new IOException("Mark not set");
            }
            in.reset();
            left = mark;
        }

        @Override
        public long skip(long n) throws IOException {
            n = Math.min(n, left);
            long skipped = in.skip(n);
            left -= skipped;
            return skipped;
        }
    }

    /**
     * Returns the length of a supplied input stream, in bytes.
     */
    public static long length(InputSupplier supplier) throws IOException {
        return asByteSource(supplier).size();
    }

    /**
     * Returns true if the supplied input streams contain the same bytes.
     *
     * @throws IOException if an I/O error occurs
     */
    public static boolean equal(InputSupplier supplier1, InputSupplier supplier2) throws IOException {
        return asByteSource(supplier1).contentEquals(asByteSource(supplier2));
    }

    /**
     * Attempts to read enough bytes from the stream to fill the given byte array,
     * with the same behavior as {@link DataInput#readFully(byte[])}.
     * Does not close the stream.
     *
     * @param in the input stream to read from.
     * @param b the buffer into which the data is read.
     * @throws EOFException if this stream reaches the end before reading all
     *     the bytes.
     * @throws IOException if an I/O error occurs.
     */
    public static void readFully(InputStream in, byte[] b) throws IOException {
        readFully(in, b, 0, b.length);
    }

    /**
     * Attempts to read {@code len} bytes from the stream into the given array
     * starting at {@code off}, with the same behavior as
     * {@link DataInput#readFully(byte[], int, int)}. Does not close the
     * stream.
     *
     * @param in the input stream to read from.
     * @param b the buffer into which the data is read.
     * @param off an int specifying the offset into the data.
     * @param len an int specifying the number of bytes to read.
     * @throws EOFException if this stream reaches the end before reading all
     *     the bytes.
     * @throws IOException if an I/O error occurs.
     */
    public static void readFully(InputStream in, byte[] b, int off, int len) throws IOException {
        int read = read(in, b, off, len);
        if (read != len) {
            throw new EOFException("reached end of stream after reading " + read + " bytes; " + len + " bytes expected");
        }
    }

    /**
     * Discards {@code n} bytes of data from the input stream. This method
     * will block until the full amount has been skipped. Does not close the
     * stream.
     *
     * @param in the input stream to read from
     * @param n the number of bytes to skip
     * @throws EOFException if this stream reaches the end before skipping all
     *     the bytes
     * @throws IOException if an I/O error occurs, or the stream does not
     *     support skipping
     */
    public static void skipFully(InputStream in, long n) throws IOException {
        long toSkip = n;
        while (n > 0) {
            long amt = in.skip(n);
            if (amt == 0) {
                // Force a blocking read to avoid infinite loop
                if (in.read() == -1) {
                    long skipped = toSkip - n;
                    throw new EOFException("reached end of stream after skipping " + skipped + " bytes; " + toSkip + " bytes expected");
                }
                n--;
            } else {
                n -= amt;
            }
        }
    }

    /**
     * Process the bytes of a supplied stream
     *
     * @param supplier the input stream factory
     * @param processor the object to which to pass the bytes of the stream
     * @return the result of the byte processor
     * @throws IOException if an I/O error occurs
     */
    public static  T readBytes(InputSupplier supplier, ByteProcessor processor) throws IOException {
        checkNotNull(supplier);
        checkNotNull(processor);
        Closer closer = Closer.create();
        try {
            InputStream in = closer.register(supplier.getInput());
            return readBytes(in, processor);
        } catch (Throwable e) {
            throw closer.rethrow(e);
        } finally {
            closer.close();
        }
    }

    /**
     * Process the bytes of the given input stream using the given processor.
     *
     * @param input the input stream to process
     * @param processor the object to which to pass the bytes of the stream
     * @return the result of the byte processor
     * @throws IOException if an I/O error occurs
     * @since 14.0
     */
    public static  T readBytes(InputStream input, ByteProcessor processor) throws IOException {
        checkNotNull(input);
        checkNotNull(processor);
        byte[] buf = new byte[BUF_SIZE];
        int read;
        do {
            read = input.read(buf);
        } while (read != -1 && processor.processBytes(buf, 0, read));
        return processor.getResult();
    }

    /**
     * Computes the hash code of the data supplied by {@code supplier} using {@code
     * hashFunction}.
     *
     * @param supplier the input stream factory
     * @param hashFunction the hash function to use to hash the data
     * @return the {@link HashCode} of all of the bytes in the input stream
     * @throws IOException if an I/O error occurs
     * @since 12.0
     */
    public static HashCode hash(InputSupplier supplier, HashFunction hashFunction) throws IOException {
        return asByteSource(supplier).hash(hashFunction);
    }

    /**
     * Reads some bytes from an input stream and stores them into the buffer array
     * {@code b}. This method blocks until {@code len} bytes of input data have
     * been read into the array, or end of file is detected. The number of bytes
     * read is returned, possibly zero. Does not close the stream.
     *
     * 

A caller can detect EOF if the number of bytes read is less than * {@code len}. All subsequent calls on the same stream will return zero. * *

If {@code b} is null, a {@code NullPointerException} is thrown. If * {@code off} is negative, or {@code len} is negative, or {@code off+len} is * greater than the length of the array {@code b}, then an * {@code IndexOutOfBoundsException} is thrown. If {@code len} is zero, then * no bytes are read. Otherwise, the first byte read is stored into element * {@code b[off]}, the next one into {@code b[off+1]}, and so on. The number * of bytes read is, at most, equal to {@code len}. * * @param in the input stream to read from * @param b the buffer into which the data is read * @param off an int specifying the offset into the data * @param len an int specifying the number of bytes to read * @return the number of bytes read * @throws IOException if an I/O error occurs */ public static int read(InputStream in, byte[] b, int off, int len) throws IOException { checkNotNull(in); checkNotNull(b); if (len < 0) { throw new IndexOutOfBoundsException("len is negative"); } int total = 0; while (total < len) { int result = in.read(b, off + total, len - total); if (result == -1) { break; } total += result; } return total; } /** * Returns an {@link InputSupplier} that returns input streams from the * an underlying supplier, where each stream starts at the given * offset and is limited to the specified number of bytes. * * @param supplier the supplier from which to get the raw streams * @param offset the offset in bytes into the underlying stream where * the returned streams will start * @param length the maximum length of the returned streams * @throws IllegalArgumentException if offset or length are negative */ public static InputSupplier slice(final InputSupplier supplier, final long offset, final long length) { return asInputSupplier(asByteSource(supplier).slice(offset, length)); } /** * Joins multiple {@link InputStream} suppliers into a single supplier. * Streams returned from the supplier will contain the concatenated data from * the streams of the underlying suppliers. * *

Only one underlying input stream will be open at a time. Closing the * joined stream will close the open underlying stream. * *

Reading from the joined stream will throw a {@link NullPointerException} * if any of the suppliers are null or return null. * * @param suppliers the suppliers to concatenate * @return a supplier that will return a stream containing the concatenated * stream data */ public static InputSupplier join(final Iterable> suppliers) { checkNotNull(suppliers); Iterable sources = Iterables.transform(suppliers, new Function, ByteSource>() { @Override public ByteSource apply(InputSupplier input) { return asByteSource(input); } }); return asInputSupplier(ByteSource.concat(sources)); } /** * Varargs form of {@link #join(Iterable)}. */ // suppress "possible heap pollution" warning in JDK7 @SuppressWarnings("unchecked") public static InputSupplier join(InputSupplier... suppliers) { return join(Arrays.asList(suppliers)); } // TODO(user): Remove these once Input/OutputSupplier methods are removed /** * Returns a view of the given {@code InputStream} supplier as a * {@code ByteSource}. * *

This method is a temporary method provided for easing migration from * suppliers to sources and sinks. * * @since 15.0 */ public static ByteSource asByteSource(final InputSupplier supplier) { checkNotNull(supplier); return new ByteSource() { @Override public InputStream openStream() throws IOException { return supplier.getInput(); } @Override public String toString() { return "ByteStreams.asByteSource(" + supplier + ")"; } }; } /** * Returns a view of the given {@code OutputStream} supplier as a * {@code ByteSink}. * *

This method is a temporary method provided for easing migration from * suppliers to sources and sinks. * * @since 15.0 */ public static ByteSink asByteSink(final OutputSupplier supplier) { checkNotNull(supplier); return new ByteSink() { @Override public OutputStream openStream() throws IOException { return supplier.getOutput(); } @Override public String toString() { return "ByteStreams.asByteSink(" + supplier + ")"; } }; } // used internally where known to be safe @SuppressWarnings("unchecked") static InputSupplier asInputSupplier(final ByteSource source) { return (InputSupplier) checkNotNull(source); } // used internally where known to be safe @SuppressWarnings("unchecked") static OutputSupplier asOutputSupplier(final ByteSink sink) { return (OutputSupplier) checkNotNull(sink); } }