From 83b35b045fd523ef4313ee81b0c91cc1ca976426 Mon Sep 17 00:00:00 2001
From: Daniel Weeks <dweeks@apache.org>
Date: Thu, 21 Apr 2022 11:41:54 -0700
Subject: [PATCH 01/15] Add RangeReadable interface for range base FileIO reads

---
 .../org/apache/iceberg/io/RangeReadable.java  | 60 +++++++++++++++++++
 .../apache/iceberg/aws/s3/S3InputStream.java  | 18 +++++-
 .../iceberg/aws/s3/TestS3InputStream.java     | 45 ++++++++++++++
 3 files changed, 122 insertions(+), 1 deletion(-)
 create mode 100644 api/src/main/java/org/apache/iceberg/io/RangeReadable.java

diff --git a/api/src/main/java/org/apache/iceberg/io/RangeReadable.java b/api/src/main/java/org/apache/iceberg/io/RangeReadable.java
new file mode 100644
index 000000000000..c338ea673580
--- /dev/null
+++ b/api/src/main/java/org/apache/iceberg/io/RangeReadable.java
@@ -0,0 +1,60 @@
+/*
+ * 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.iceberg.io;
+
+/**
+ * {@code RangeReadable} is an interface that allows for implementations
+ * of {@link InputFile} streams to perform positional, range-based reads, which
+ * are more efficient than unbounded reads in many cloud provider object stores.
+ *
+ * Thread safety is not a requirement of the interface and is left to the
+ * implementation.
+ *
+ * If the implementation is also a {@link SeekableInputStream}, the position
+ * of the stream is not required to be updated based on the positional reads
+ * performed by this interface.  Usage of {@link SeekableInputStream} should
+ * always seek to the appropriate position for {@link java.io.InputStream}
+ * based reads.
+ *
+ */
+public interface RangeReadable extends AutoCloseable {
+
+  /**
+   * Fill the provided buffer with the contents of the input source starting
+   * at {@code position} for the given {@code offset} and {@code length}.
+   *
+   * @param position start position of the read
+   * @param buffer target buffer to copy data
+   * @param offset offset in the buffer to copy the data
+   * @param length size of the read
+   */
+  void readFully(long position, byte [] buffer, int offset, int length);
+
+  /**
+   * Fill the entire buffer with the contents of the input source starting
+   * at {@code position}.
+   *
+   * @param position start position of the read
+   * @param buffer target buffer to copy data
+   */
+  default void readFully(long position, byte [] buffer) {
+    readFully(position, buffer, 0, buffer.length);
+  }
+}
diff --git a/aws/src/main/java/org/apache/iceberg/aws/s3/S3InputStream.java b/aws/src/main/java/org/apache/iceberg/aws/s3/S3InputStream.java
index 394449aee147..3c7c5c9c74e9 100644
--- a/aws/src/main/java/org/apache/iceberg/aws/s3/S3InputStream.java
+++ b/aws/src/main/java/org/apache/iceberg/aws/s3/S3InputStream.java
@@ -25,6 +25,7 @@
 import org.apache.iceberg.aws.AwsProperties;
 import org.apache.iceberg.io.FileIOMetricsContext;
 import org.apache.iceberg.io.SeekableInputStream;
+import org.apache.iceberg.io.RangeReadable;
 import org.apache.iceberg.metrics.MetricsContext;
 import org.apache.iceberg.metrics.MetricsContext.Counter;
 import org.apache.iceberg.metrics.MetricsContext.Unit;
@@ -33,11 +34,13 @@
 import org.apache.iceberg.relocated.com.google.common.io.ByteStreams;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
+import software.amazon.awssdk.core.ResponseBytes;
 import software.amazon.awssdk.core.sync.ResponseTransformer;
 import software.amazon.awssdk.services.s3.S3Client;
 import software.amazon.awssdk.services.s3.model.GetObjectRequest;
+import software.amazon.awssdk.services.s3.model.GetObjectResponse;
 
-class S3InputStream extends SeekableInputStream {
+class S3InputStream extends SeekableInputStream implements RangeReadable {
   private static final Logger LOG = LoggerFactory.getLogger(S3InputStream.class);
 
   private final StackTraceElement[] createStack;
@@ -111,6 +114,19 @@ public int read(byte[] b, int off, int len) throws IOException {
     return bytesRead;
   }
 
+  @Override
+  public void readFully(long position, byte[] buffer, int offset, int length) {
+    GetObjectRequest.Builder requestBuilder = GetObjectRequest.builder()
+        .bucket(location.bucket())
+        .key(location.key())
+        .range(String.format("bytes=%s-%s", position, position+length));
+
+    S3RequestUtil.configureEncryption(awsProperties, requestBuilder);
+
+    ResponseBytes<GetObjectResponse> response = s3.getObject(requestBuilder.build(), ResponseTransformer.toBytes());
+    System.arraycopy(response.asByteArrayUnsafe(), 0, buffer, offset, length);
+  }
+
   @Override
   public void close() throws IOException {
     super.close();
diff --git a/aws/src/test/java/org/apache/iceberg/aws/s3/TestS3InputStream.java b/aws/src/test/java/org/apache/iceberg/aws/s3/TestS3InputStream.java
index 9568ac600882..e90cbbb3d5dc 100644
--- a/aws/src/test/java/org/apache/iceberg/aws/s3/TestS3InputStream.java
+++ b/aws/src/test/java/org/apache/iceberg/aws/s3/TestS3InputStream.java
@@ -25,6 +25,7 @@
 import java.util.Random;
 import org.apache.commons.io.IOUtils;
 import org.apache.iceberg.io.SeekableInputStream;
+import org.apache.iceberg.io.RangeReadable;
 import org.junit.Before;
 import org.junit.ClassRule;
 import org.junit.Test;
@@ -105,6 +106,50 @@ private void readAndCheck(SeekableInputStream in, long rangeStart, int size, byt
     assertArrayEquals(Arrays.copyOfRange(original, (int) rangeStart, (int) rangeEnd), actual);
   }
 
+  @Test
+  public void testRangeRead() throws Exception {
+    S3URI uri = new S3URI("s3://bucket/path/to/range-read.dat");
+    int dataSize = 1024 * 1024 * 10;
+    byte[] expected = randomData(dataSize);
+    byte[] actual = new byte[dataSize];
+
+    long position;
+    int offset;
+    int length;
+
+    writeS3Data(uri, expected);
+
+    try (RangeReadable in = new S3InputStream(s3, uri)) {
+      // first 1k
+      position = 0;
+      offset = 0;
+      length = 1024;
+      readAndCheckRanges(in, expected, position, actual, offset, length);
+
+      // last 1k
+      position = dataSize - 1024;
+      offset = dataSize - 1024;
+      length = 1024;
+      readAndCheckRanges(in, expected, position, actual, offset, length);
+
+      // middle 2k
+      position = dataSize/2 - 1024;
+      offset = dataSize/2 - 1024;
+      length = 1024*2;
+      readAndCheckRanges(in, expected, position, actual, offset, length);
+    }
+  }
+
+  private void readAndCheckRanges(
+      RangeReadable in, byte [] original, long position, byte [] buffer, int offset,
+      int length) {
+    in.readFully(position, buffer, offset, length);
+
+    assertArrayEquals(
+        Arrays.copyOfRange(original, offset, offset+length),
+        Arrays.copyOfRange(buffer, offset, offset+length));
+  }
+
   @Test
   public void testClose() throws Exception {
     S3URI uri = new S3URI("s3://bucket/path/to/closed.dat");

From c01cfb9e869ffeb43b35f81e3518ed5d24ba3e74 Mon Sep 17 00:00:00 2001
From: Daniel Weeks <dweeks@apache.org>
Date: Thu, 21 Apr 2022 12:14:16 -0700
Subject: [PATCH 02/15] Checkstyle

---
 .../main/java/org/apache/iceberg/aws/s3/S3InputStream.java    | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/aws/src/main/java/org/apache/iceberg/aws/s3/S3InputStream.java b/aws/src/main/java/org/apache/iceberg/aws/s3/S3InputStream.java
index 3c7c5c9c74e9..c55041e5c29d 100644
--- a/aws/src/main/java/org/apache/iceberg/aws/s3/S3InputStream.java
+++ b/aws/src/main/java/org/apache/iceberg/aws/s3/S3InputStream.java
@@ -24,8 +24,8 @@
 import java.util.Arrays;
 import org.apache.iceberg.aws.AwsProperties;
 import org.apache.iceberg.io.FileIOMetricsContext;
-import org.apache.iceberg.io.SeekableInputStream;
 import org.apache.iceberg.io.RangeReadable;
+import org.apache.iceberg.io.SeekableInputStream;
 import org.apache.iceberg.metrics.MetricsContext;
 import org.apache.iceberg.metrics.MetricsContext.Counter;
 import org.apache.iceberg.metrics.MetricsContext.Unit;
@@ -119,7 +119,7 @@ public void readFully(long position, byte[] buffer, int offset, int length) {
     GetObjectRequest.Builder requestBuilder = GetObjectRequest.builder()
         .bucket(location.bucket())
         .key(location.key())
-        .range(String.format("bytes=%s-%s", position, position+length));
+        .range(String.format("bytes=%s-%s", position, position + length));
 
     S3RequestUtil.configureEncryption(awsProperties, requestBuilder);
 

From 4ae673c4da83de4f9db3064ac218c354175ef56b Mon Sep 17 00:00:00 2001
From: Daniel Weeks <dweeks@apache.org>
Date: Thu, 21 Apr 2022 12:15:41 -0700
Subject: [PATCH 03/15] Style

---
 api/src/main/java/org/apache/iceberg/io/RangeReadable.java | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/api/src/main/java/org/apache/iceberg/io/RangeReadable.java b/api/src/main/java/org/apache/iceberg/io/RangeReadable.java
index c338ea673580..3b895460f57c 100644
--- a/api/src/main/java/org/apache/iceberg/io/RangeReadable.java
+++ b/api/src/main/java/org/apache/iceberg/io/RangeReadable.java
@@ -45,7 +45,7 @@ public interface RangeReadable extends AutoCloseable {
    * @param offset offset in the buffer to copy the data
    * @param length size of the read
    */
-  void readFully(long position, byte [] buffer, int offset, int length);
+  void readFully(long position, byte[] buffer, int offset, int length);
 
   /**
    * Fill the entire buffer with the contents of the input source starting
@@ -54,7 +54,7 @@ public interface RangeReadable extends AutoCloseable {
    * @param position start position of the read
    * @param buffer target buffer to copy data
    */
-  default void readFully(long position, byte [] buffer) {
+  default void readFully(long position, byte[] buffer) {
     readFully(position, buffer, 0, buffer.length);
   }
 }

From b05b9688eb89702ca60ebff2cbf65667a8592100 Mon Sep 17 00:00:00 2001
From: Daniel Weeks <dweeks@apache.org>
Date: Thu, 21 Apr 2022 12:25:22 -0700
Subject: [PATCH 04/15] Checkstyle

---
 .../org/apache/iceberg/aws/s3/TestS3InputStream.java | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/aws/src/test/java/org/apache/iceberg/aws/s3/TestS3InputStream.java b/aws/src/test/java/org/apache/iceberg/aws/s3/TestS3InputStream.java
index e90cbbb3d5dc..efa29920e41c 100644
--- a/aws/src/test/java/org/apache/iceberg/aws/s3/TestS3InputStream.java
+++ b/aws/src/test/java/org/apache/iceberg/aws/s3/TestS3InputStream.java
@@ -24,8 +24,8 @@
 import java.util.Arrays;
 import java.util.Random;
 import org.apache.commons.io.IOUtils;
-import org.apache.iceberg.io.SeekableInputStream;
 import org.apache.iceberg.io.RangeReadable;
+import org.apache.iceberg.io.SeekableInputStream;
 import org.junit.Before;
 import org.junit.ClassRule;
 import org.junit.Test;
@@ -133,9 +133,9 @@ public void testRangeRead() throws Exception {
       readAndCheckRanges(in, expected, position, actual, offset, length);
 
       // middle 2k
-      position = dataSize/2 - 1024;
-      offset = dataSize/2 - 1024;
-      length = 1024*2;
+      position = dataSize / 2 - 1024;
+      offset = dataSize / 2 - 1024;
+      length = 1024 * 2;
       readAndCheckRanges(in, expected, position, actual, offset, length);
     }
   }
@@ -146,8 +146,8 @@ private void readAndCheckRanges(
     in.readFully(position, buffer, offset, length);
 
     assertArrayEquals(
-        Arrays.copyOfRange(original, offset, offset+length),
-        Arrays.copyOfRange(buffer, offset, offset+length));
+        Arrays.copyOfRange(original, offset, offset + length),
+        Arrays.copyOfRange(buffer, offset, offset + length));
   }
 
   @Test

From 19c376db1d87f0ecbfc05f4042e055d912653100 Mon Sep 17 00:00:00 2001
From: Daniel Weeks <dweeks@apache.org>
Date: Sat, 23 Apr 2022 12:14:55 -0700
Subject: [PATCH 05/15] Add readTail

---
 .../java/org/apache/iceberg/io/IOUtil.java    | 43 +++++++++++++++++++
 .../org/apache/iceberg/io/RangeReadable.java  | 30 +++++++++++--
 .../apache/iceberg/aws/s3/S3InputStream.java  | 27 +++++++++---
 .../iceberg/aws/s3/TestS3InputStream.java     |  5 +--
 4 files changed, 93 insertions(+), 12 deletions(-)
 create mode 100644 api/src/main/java/org/apache/iceberg/io/IOUtil.java

diff --git a/api/src/main/java/org/apache/iceberg/io/IOUtil.java b/api/src/main/java/org/apache/iceberg/io/IOUtil.java
new file mode 100644
index 000000000000..e3658ccc1e55
--- /dev/null
+++ b/api/src/main/java/org/apache/iceberg/io/IOUtil.java
@@ -0,0 +1,43 @@
+/*
+ * 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 org.apache.iceberg.io;
+
+import java.io.IOException;
+import java.io.InputStream;
+
+public class IOUtil {
+  /**
+   * Reads a buffer from a stream, making multiple read calls if necessary.
+   *
+   * @param stream an InputStream to read from
+   * @param bytes a buffer
+   * @param offset starting offset in the buffer for the data
+   * @param length length of bytes to copy from the input stream to the buffer
+   * @throws IOException if there is an error while reading
+   */
+  @SuppressWarnings("checkstyle:InnerAssignment")
+  public static void readFully(
+      InputStream stream, byte[] bytes, int offset, int length) throws IOException {
+    int pos = offset;
+    int bytesRead;
+    while ((length - pos) > 0 && (bytesRead = stream.read(bytes, pos, length - pos)) > 0) {
+      pos += bytesRead;
+    }
+
+    if(pos != length) {
+      throw new IOException("End of stream reached before completing read");
+    }
+  }
+}
diff --git a/api/src/main/java/org/apache/iceberg/io/RangeReadable.java b/api/src/main/java/org/apache/iceberg/io/RangeReadable.java
index 3b895460f57c..ababa7aacd1f 100644
--- a/api/src/main/java/org/apache/iceberg/io/RangeReadable.java
+++ b/api/src/main/java/org/apache/iceberg/io/RangeReadable.java
@@ -19,6 +19,9 @@
 
 package org.apache.iceberg.io;
 
+import java.io.Closeable;
+import java.io.IOException;
+
 /**
  * {@code RangeReadable} is an interface that allows for implementations
  * of {@link InputFile} streams to perform positional, range-based reads, which
@@ -34,7 +37,7 @@
  * based reads.
  *
  */
-public interface RangeReadable extends AutoCloseable {
+public interface RangeReadable extends Closeable {
 
   /**
    * Fill the provided buffer with the contents of the input source starting
@@ -45,7 +48,7 @@ public interface RangeReadable extends AutoCloseable {
    * @param offset offset in the buffer to copy the data
    * @param length size of the read
    */
-  void readFully(long position, byte[] buffer, int offset, int length);
+  void readFully(long position, byte[] buffer, int offset, int length) throws IOException;
 
   /**
    * Fill the entire buffer with the contents of the input source starting
@@ -54,7 +57,28 @@ public interface RangeReadable extends AutoCloseable {
    * @param position start position of the read
    * @param buffer target buffer to copy data
    */
-  default void readFully(long position, byte[] buffer) {
+  default void readFully(long position, byte[] buffer) throws IOException {
     readFully(position, buffer, 0, buffer.length);
   }
+
+  /**
+   * Read the last {@code length} bytes from the file into the provided
+   * buffer at the given offset.
+   *
+   * @param buffer the buffer to write data into
+   * @param offset the offset in the buffer to start writing
+   * @param length the number of bytes from the end of the object to read
+   * @throws IOException if an error occurs while reading
+   */
+  void readTail(byte [] buffer, int offset, int length) throws IOException;
+
+  /**
+   * Read the full size of the buffer from the end of the file.
+   * 
+   * @param buffer the buffer to write data into
+   * @throws IOException if an error occurs while reading
+   */
+  default void readTail(byte [] buffer) throws IOException {
+    readTail(buffer, 0, buffer.length);
+  }
 }
diff --git a/aws/src/main/java/org/apache/iceberg/aws/s3/S3InputStream.java b/aws/src/main/java/org/apache/iceberg/aws/s3/S3InputStream.java
index c55041e5c29d..5a9f0cc2d45e 100644
--- a/aws/src/main/java/org/apache/iceberg/aws/s3/S3InputStream.java
+++ b/aws/src/main/java/org/apache/iceberg/aws/s3/S3InputStream.java
@@ -24,6 +24,7 @@
 import java.util.Arrays;
 import org.apache.iceberg.aws.AwsProperties;
 import org.apache.iceberg.io.FileIOMetricsContext;
+import org.apache.iceberg.io.IOUtil;
 import org.apache.iceberg.io.RangeReadable;
 import org.apache.iceberg.io.SeekableInputStream;
 import org.apache.iceberg.metrics.MetricsContext;
@@ -34,11 +35,9 @@
 import org.apache.iceberg.relocated.com.google.common.io.ByteStreams;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-import software.amazon.awssdk.core.ResponseBytes;
 import software.amazon.awssdk.core.sync.ResponseTransformer;
 import software.amazon.awssdk.services.s3.S3Client;
 import software.amazon.awssdk.services.s3.model.GetObjectRequest;
-import software.amazon.awssdk.services.s3.model.GetObjectResponse;
 
 class S3InputStream extends SeekableInputStream implements RangeReadable {
   private static final Logger LOG = LoggerFactory.getLogger(S3InputStream.class);
@@ -115,16 +114,32 @@ public int read(byte[] b, int off, int len) throws IOException {
   }
 
   @Override
-  public void readFully(long position, byte[] buffer, int offset, int length) {
+  public void readFully(long position, byte[] buffer, int offset, int length) throws IOException {
+    Preconditions.checkPositionIndexes(offset, offset + length, buffer.length);
+
+    String range = String.format("bytes=%s-%s", position, position + length - 1);
+
+    IOUtil.readFully(readRange(range), buffer, offset, length);
+  }
+
+  @Override
+  public void readTail(byte[] buffer, int offset, int length) throws IOException {
+    Preconditions.checkPositionIndexes(offset, offset + length, buffer.length);
+
+    String range = String.format("bytes=-%s", length);
+
+    IOUtil.readFully(readRange(range), buffer, offset, length);
+  }
+
+  private InputStream readRange(String range) {
     GetObjectRequest.Builder requestBuilder = GetObjectRequest.builder()
         .bucket(location.bucket())
         .key(location.key())
-        .range(String.format("bytes=%s-%s", position, position + length));
+        .range(range);
 
     S3RequestUtil.configureEncryption(awsProperties, requestBuilder);
 
-    ResponseBytes<GetObjectResponse> response = s3.getObject(requestBuilder.build(), ResponseTransformer.toBytes());
-    System.arraycopy(response.asByteArrayUnsafe(), 0, buffer, offset, length);
+    return s3.getObject(requestBuilder.build(), ResponseTransformer.toInputStream());
   }
 
   @Override
diff --git a/aws/src/test/java/org/apache/iceberg/aws/s3/TestS3InputStream.java b/aws/src/test/java/org/apache/iceberg/aws/s3/TestS3InputStream.java
index efa29920e41c..17770339be0d 100644
--- a/aws/src/test/java/org/apache/iceberg/aws/s3/TestS3InputStream.java
+++ b/aws/src/test/java/org/apache/iceberg/aws/s3/TestS3InputStream.java
@@ -129,7 +129,6 @@ public void testRangeRead() throws Exception {
       // last 1k
       position = dataSize - 1024;
       offset = dataSize - 1024;
-      length = 1024;
       readAndCheckRanges(in, expected, position, actual, offset, length);
 
       // middle 2k
@@ -140,9 +139,9 @@ public void testRangeRead() throws Exception {
     }
   }
 
-  private void readAndCheckRanges(
+  private void readAndCheckRanges (
       RangeReadable in, byte [] original, long position, byte [] buffer, int offset,
-      int length) {
+      int length) throws IOException {
     in.readFully(position, buffer, offset, length);
 
     assertArrayEquals(

From 895a77ad635e131a05b1613b5d982a47db85a3d7 Mon Sep 17 00:00:00 2001
From: Daniel Weeks <dweeks@apache.org>
Date: Sat, 23 Apr 2022 12:23:06 -0700
Subject: [PATCH 06/15] Checkstyle

---
 .../java/org/apache/iceberg/io/IOUtil.java    | 29 ++++++++++++-------
 .../org/apache/iceberg/io/RangeReadable.java  |  2 +-
 2 files changed, 20 insertions(+), 11 deletions(-)

diff --git a/api/src/main/java/org/apache/iceberg/io/IOUtil.java b/api/src/main/java/org/apache/iceberg/io/IOUtil.java
index e3658ccc1e55..3b4c6c041156 100644
--- a/api/src/main/java/org/apache/iceberg/io/IOUtil.java
+++ b/api/src/main/java/org/apache/iceberg/io/IOUtil.java
@@ -1,15 +1,20 @@
 /*
- * 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
+ * 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
+ *   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.
+ * 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.iceberg.io;
@@ -18,6 +23,10 @@
 import java.io.InputStream;
 
 public class IOUtil {
+  // not meant to be instantiated
+  private IOUtil() {
+  }
+
   /**
    * Reads a buffer from a stream, making multiple read calls if necessary.
    *
@@ -36,7 +45,7 @@ public static void readFully(
       pos += bytesRead;
     }
 
-    if(pos != length) {
+    if (pos != length) {
       throw new IOException("End of stream reached before completing read");
     }
   }
diff --git a/api/src/main/java/org/apache/iceberg/io/RangeReadable.java b/api/src/main/java/org/apache/iceberg/io/RangeReadable.java
index ababa7aacd1f..bd3253da620a 100644
--- a/api/src/main/java/org/apache/iceberg/io/RangeReadable.java
+++ b/api/src/main/java/org/apache/iceberg/io/RangeReadable.java
@@ -74,7 +74,7 @@ default void readFully(long position, byte[] buffer) throws IOException {
 
   /**
    * Read the full size of the buffer from the end of the file.
-   * 
+   *
    * @param buffer the buffer to write data into
    * @throws IOException if an error occurs while reading
    */

From 298c17e340627910927f0a1c1b44e74f1ea14e5c Mon Sep 17 00:00:00 2001
From: Daniel Weeks <dweeks@apache.org>
Date: Sat, 23 Apr 2022 12:26:32 -0700
Subject: [PATCH 07/15] Relocate IOUtil to core

---
 {api => core}/src/main/java/org/apache/iceberg/io/IOUtil.java | 0
 1 file changed, 0 insertions(+), 0 deletions(-)
 rename {api => core}/src/main/java/org/apache/iceberg/io/IOUtil.java (100%)

diff --git a/api/src/main/java/org/apache/iceberg/io/IOUtil.java b/core/src/main/java/org/apache/iceberg/io/IOUtil.java
similarity index 100%
rename from api/src/main/java/org/apache/iceberg/io/IOUtil.java
rename to core/src/main/java/org/apache/iceberg/io/IOUtil.java

From 961e7898b857233feac24b297d125f037c4b9023 Mon Sep 17 00:00:00 2001
From: Daniel Weeks <dweeks@apache.org>
Date: Sat, 23 Apr 2022 13:05:12 -0700
Subject: [PATCH 08/15] Fix readFully

---
 core/src/main/java/org/apache/iceberg/io/IOUtil.java | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/core/src/main/java/org/apache/iceberg/io/IOUtil.java b/core/src/main/java/org/apache/iceberg/io/IOUtil.java
index 3b4c6c041156..0c2df71871a4 100644
--- a/core/src/main/java/org/apache/iceberg/io/IOUtil.java
+++ b/core/src/main/java/org/apache/iceberg/io/IOUtil.java
@@ -37,15 +37,15 @@ private IOUtil() {
    * @throws IOException if there is an error while reading
    */
   @SuppressWarnings("checkstyle:InnerAssignment")
-  public static void readFully(
-      InputStream stream, byte[] bytes, int offset, int length) throws IOException {
+  public static void readFully(InputStream stream, byte[] bytes, int offset, int length) throws IOException {
     int pos = offset;
-    int bytesRead;
-    while ((length - pos) > 0 && (bytesRead = stream.read(bytes, pos, length - pos)) > 0) {
+    int bytesRead = 0;
+
+    while ((length - bytesRead) > 0 && (bytesRead = stream.read(bytes, pos, length - bytesRead)) > 0) {
       pos += bytesRead;
     }
 
-    if (pos != length) {
+    if (bytesRead != length) {
       throw new IOException("End of stream reached before completing read");
     }
   }

From 1f92f2264b7ce7b5d05552417e3c771813ba0f05 Mon Sep 17 00:00:00 2001
From: Daniel Weeks <dweeks@apache.org>
Date: Sat, 23 Apr 2022 13:19:54 -0700
Subject: [PATCH 09/15] Update readTail to return actual size read before EOF

---
 .../org/apache/iceberg/io/RangeReadable.java  | 11 +++++-----
 .../apache/iceberg/aws/s3/S3InputStream.java  |  4 ++--
 .../java/org/apache/iceberg/io/IOUtil.java    | 21 ++++++++++++++++---
 3 files changed, 26 insertions(+), 10 deletions(-)

diff --git a/api/src/main/java/org/apache/iceberg/io/RangeReadable.java b/api/src/main/java/org/apache/iceberg/io/RangeReadable.java
index bd3253da620a..fafdd7b02037 100644
--- a/api/src/main/java/org/apache/iceberg/io/RangeReadable.java
+++ b/api/src/main/java/org/apache/iceberg/io/RangeReadable.java
@@ -62,23 +62,24 @@ default void readFully(long position, byte[] buffer) throws IOException {
   }
 
   /**
-   * Read the last {@code length} bytes from the file into the provided
-   * buffer at the given offset.
+   * Read the last {@code length} bytes from the file.
    *
    * @param buffer the buffer to write data into
    * @param offset the offset in the buffer to start writing
    * @param length the number of bytes from the end of the object to read
+   * @return the actual number of bytes read
    * @throws IOException if an error occurs while reading
    */
-  void readTail(byte [] buffer, int offset, int length) throws IOException;
+  int readTail(byte [] buffer, int offset, int length) throws IOException;
 
   /**
    * Read the full size of the buffer from the end of the file.
    *
    * @param buffer the buffer to write data into
+   * @return the actual number of bytes read
    * @throws IOException if an error occurs while reading
    */
-  default void readTail(byte [] buffer) throws IOException {
-    readTail(buffer, 0, buffer.length);
+  default int readTail(byte [] buffer) throws IOException {
+    return readTail(buffer, 0, buffer.length);
   }
 }
diff --git a/aws/src/main/java/org/apache/iceberg/aws/s3/S3InputStream.java b/aws/src/main/java/org/apache/iceberg/aws/s3/S3InputStream.java
index 5a9f0cc2d45e..b62b49f34676 100644
--- a/aws/src/main/java/org/apache/iceberg/aws/s3/S3InputStream.java
+++ b/aws/src/main/java/org/apache/iceberg/aws/s3/S3InputStream.java
@@ -123,12 +123,12 @@ public void readFully(long position, byte[] buffer, int offset, int length) thro
   }
 
   @Override
-  public void readTail(byte[] buffer, int offset, int length) throws IOException {
+  public int readTail(byte[] buffer, int offset, int length) throws IOException {
     Preconditions.checkPositionIndexes(offset, offset + length, buffer.length);
 
     String range = String.format("bytes=-%s", length);
 
-    IOUtil.readFully(readRange(range), buffer, offset, length);
+    return IOUtil.readToEnd(readRange(range), buffer, offset, length);
   }
 
   private InputStream readRange(String range) {
diff --git a/core/src/main/java/org/apache/iceberg/io/IOUtil.java b/core/src/main/java/org/apache/iceberg/io/IOUtil.java
index 0c2df71871a4..cfda22771259 100644
--- a/core/src/main/java/org/apache/iceberg/io/IOUtil.java
+++ b/core/src/main/java/org/apache/iceberg/io/IOUtil.java
@@ -38,6 +38,23 @@ private IOUtil() {
    */
   @SuppressWarnings("checkstyle:InnerAssignment")
   public static void readFully(InputStream stream, byte[] bytes, int offset, int length) throws IOException {
+    if (readToEnd(stream, bytes, offset, length) != length) {
+      throw new IOException("End of stream reached before completing read");
+    }
+  }
+
+  /**
+   * Reads a buffer from a stream, making multiple read calls if necessary
+   * returning the number of bytes read until end of stream.
+   *
+   * @param stream an InputStream to read from
+   * @param bytes a buffer
+   * @param offset starting offset in the buffer for the data
+   * @param length length of bytes to copy from the input stream to the buffer
+   * @throws IOException if there is an error while reading
+   */
+  @SuppressWarnings("checkstyle:InnerAssignment")
+  public static int readToEnd(InputStream stream, byte[] bytes, int offset, int length) throws IOException {
     int pos = offset;
     int bytesRead = 0;
 
@@ -45,8 +62,6 @@ public static void readFully(InputStream stream, byte[] bytes, int offset, int l
       pos += bytesRead;
     }
 
-    if (bytesRead != length) {
-      throw new IOException("End of stream reached before completing read");
-    }
+    return bytesRead;
   }
 }

From 36032b1eff6651ddeef36c7465f19c38d540a843 Mon Sep 17 00:00:00 2001
From: Daniel Weeks <dweeks@apache.org>
Date: Sat, 23 Apr 2022 13:21:35 -0700
Subject: [PATCH 10/15] Cleanup comments

---
 core/src/main/java/org/apache/iceberg/io/IOUtil.java | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/core/src/main/java/org/apache/iceberg/io/IOUtil.java b/core/src/main/java/org/apache/iceberg/io/IOUtil.java
index cfda22771259..d60f6983cdd9 100644
--- a/core/src/main/java/org/apache/iceberg/io/IOUtil.java
+++ b/core/src/main/java/org/apache/iceberg/io/IOUtil.java
@@ -28,10 +28,10 @@ private IOUtil() {
   }
 
   /**
-   * Reads a buffer from a stream, making multiple read calls if necessary.
+   * Reads into a buffer from a stream, making multiple read calls if necessary.
    *
    * @param stream an InputStream to read from
-   * @param bytes a buffer
+   * @param bytes a buffer to write into
    * @param offset starting offset in the buffer for the data
    * @param length length of bytes to copy from the input stream to the buffer
    * @throws IOException if there is an error while reading
@@ -44,11 +44,11 @@ public static void readFully(InputStream stream, byte[] bytes, int offset, int l
   }
 
   /**
-   * Reads a buffer from a stream, making multiple read calls if necessary
+   * Reads into a buffer from a stream, making multiple read calls if necessary
    * returning the number of bytes read until end of stream.
    *
    * @param stream an InputStream to read from
-   * @param bytes a buffer
+   * @param bytes a buffer to write into
    * @param offset starting offset in the buffer for the data
    * @param length length of bytes to copy from the input stream to the buffer
    * @throws IOException if there is an error while reading

From ec6c81d9353e7d2356d662f670337320588550b5 Mon Sep 17 00:00:00 2001
From: Daniel Weeks <dweeks@apache.org>
Date: Sat, 23 Apr 2022 18:06:17 -0700
Subject: [PATCH 11/15] Checkstyle

---
 .../test/java/org/apache/iceberg/aws/s3/TestS3InputStream.java  | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/aws/src/test/java/org/apache/iceberg/aws/s3/TestS3InputStream.java b/aws/src/test/java/org/apache/iceberg/aws/s3/TestS3InputStream.java
index 17770339be0d..417ba16f71ad 100644
--- a/aws/src/test/java/org/apache/iceberg/aws/s3/TestS3InputStream.java
+++ b/aws/src/test/java/org/apache/iceberg/aws/s3/TestS3InputStream.java
@@ -139,7 +139,7 @@ public void testRangeRead() throws Exception {
     }
   }
 
-  private void readAndCheckRanges (
+  private void readAndCheckRanges(
       RangeReadable in, byte [] original, long position, byte [] buffer, int offset,
       int length) throws IOException {
     in.readFully(position, buffer, offset, length);

From 859602081169c9ef6acd23e52ad3179958e6bcee Mon Sep 17 00:00:00 2001
From: Ryan Blue <blue@apache.org>
Date: Sun, 24 Apr 2022 09:37:45 -0700
Subject: [PATCH 12/15] Replace readFully implementation with one from Parquet.

---
 .../apache/iceberg/aws/s3/S3InputStream.java  |   2 +-
 .../java/org/apache/iceberg/io/IOUtil.java    |  24 ++--
 .../apache/iceberg/io/MockInputStream.java    |  57 ++++++++
 .../org/apache/iceberg/io/TestIOUtil.java     | 122 ++++++++++++++++++
 4 files changed, 196 insertions(+), 9 deletions(-)
 create mode 100644 core/src/test/java/org/apache/iceberg/io/MockInputStream.java
 create mode 100644 core/src/test/java/org/apache/iceberg/io/TestIOUtil.java

diff --git a/aws/src/main/java/org/apache/iceberg/aws/s3/S3InputStream.java b/aws/src/main/java/org/apache/iceberg/aws/s3/S3InputStream.java
index b62b49f34676..92d0f3f3eae9 100644
--- a/aws/src/main/java/org/apache/iceberg/aws/s3/S3InputStream.java
+++ b/aws/src/main/java/org/apache/iceberg/aws/s3/S3InputStream.java
@@ -128,7 +128,7 @@ public int readTail(byte[] buffer, int offset, int length) throws IOException {
 
     String range = String.format("bytes=-%s", length);
 
-    return IOUtil.readToEnd(readRange(range), buffer, offset, length);
+    return IOUtil.readRemaining(readRange(range), buffer, offset, length);
   }
 
   private InputStream readRange(String range) {
diff --git a/core/src/main/java/org/apache/iceberg/io/IOUtil.java b/core/src/main/java/org/apache/iceberg/io/IOUtil.java
index d60f6983cdd9..0daf4a019358 100644
--- a/core/src/main/java/org/apache/iceberg/io/IOUtil.java
+++ b/core/src/main/java/org/apache/iceberg/io/IOUtil.java
@@ -19,6 +19,7 @@
 
 package org.apache.iceberg.io;
 
+import java.io.EOFException;
 import java.io.IOException;
 import java.io.InputStream;
 
@@ -34,12 +35,14 @@ private IOUtil() {
    * @param bytes a buffer to write into
    * @param offset starting offset in the buffer for the data
    * @param length length of bytes to copy from the input stream to the buffer
+   * @throws EOFException if the end of the stream is reached before reading length bytes
    * @throws IOException if there is an error while reading
    */
-  @SuppressWarnings("checkstyle:InnerAssignment")
   public static void readFully(InputStream stream, byte[] bytes, int offset, int length) throws IOException {
-    if (readToEnd(stream, bytes, offset, length) != length) {
-      throw new IOException("End of stream reached before completing read");
+    int bytesRead = readRemaining(stream, bytes, offset, length);
+    if (bytesRead < length) {
+      throw new EOFException(
+          "Reached the end of stream with " + (length - bytesRead) + " bytes left to read");
     }
   }
 
@@ -51,17 +54,22 @@ public static void readFully(InputStream stream, byte[] bytes, int offset, int l
    * @param bytes a buffer to write into
    * @param offset starting offset in the buffer for the data
    * @param length length of bytes to copy from the input stream to the buffer
+   * @return the number of bytes read
    * @throws IOException if there is an error while reading
    */
-  @SuppressWarnings("checkstyle:InnerAssignment")
-  public static int readToEnd(InputStream stream, byte[] bytes, int offset, int length) throws IOException {
+  public static int readRemaining(InputStream stream, byte[] bytes, int offset, int length) throws IOException {
     int pos = offset;
-    int bytesRead = 0;
+    int remaining = length;
+    while (remaining > 0) {
+      int bytesRead = stream.read(bytes, pos, remaining);
+      if (bytesRead < 0) {
+        break;
+      }
 
-    while ((length - bytesRead) > 0 && (bytesRead = stream.read(bytes, pos, length - bytesRead)) > 0) {
+      remaining -= bytesRead;
       pos += bytesRead;
     }
 
-    return bytesRead;
+    return length - remaining;
   }
 }
diff --git a/core/src/test/java/org/apache/iceberg/io/MockInputStream.java b/core/src/test/java/org/apache/iceberg/io/MockInputStream.java
new file mode 100644
index 000000000000..03bdc2d97a06
--- /dev/null
+++ b/core/src/test/java/org/apache/iceberg/io/MockInputStream.java
@@ -0,0 +1,57 @@
+/*
+ * 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.iceberg.io;
+
+import java.io.ByteArrayInputStream;
+
+class MockInputStream extends ByteArrayInputStream {
+
+  static final byte[] TEST_ARRAY = new byte[] { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };
+
+  private int[] lengths;
+  private int current = 0;
+  MockInputStream(int... actualReadLengths) {
+    super(TEST_ARRAY);
+    this.lengths = actualReadLengths;
+  }
+
+  @Override
+  public synchronized int read(byte[] b, int off, int len) {
+    if (current < lengths.length) {
+      if (len <= lengths[current]) {
+        // when len == lengths[current], the next read will by 0 bytes
+        int bytesRead = super.read(b, off, len);
+        lengths[current] -= bytesRead;
+        return bytesRead;
+      } else {
+        int bytesRead = super.read(b, off, lengths[current]);
+        current += 1;
+        return bytesRead;
+      }
+    } else {
+      return super.read(b, off, len);
+    }
+  }
+
+  public long getPos() {
+    return this.pos;
+  }
+}
+
diff --git a/core/src/test/java/org/apache/iceberg/io/TestIOUtil.java b/core/src/test/java/org/apache/iceberg/io/TestIOUtil.java
new file mode 100644
index 000000000000..dae92785fc65
--- /dev/null
+++ b/core/src/test/java/org/apache/iceberg/io/TestIOUtil.java
@@ -0,0 +1,122 @@
+/*
+ * 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.iceberg.io;
+
+import java.io.EOFException;
+import java.io.IOException;
+import java.util.Arrays;
+import org.apache.iceberg.AssertHelpers;
+import org.junit.Assert;
+import org.junit.Test;
+
+public class TestIOUtil {
+  @Test
+  public void testReadFully() throws Exception {
+    byte[] buffer = new byte[5];
+
+    MockInputStream stream = new MockInputStream();
+    IOUtil.readFully(stream, buffer, 0, buffer.length);
+
+    Assert.assertArrayEquals("Byte array contents should match",
+        Arrays.copyOfRange(MockInputStream.TEST_ARRAY, 0, 5), buffer);
+    Assert.assertEquals("Stream position should reflect bytes read", 5, stream.getPos());
+  }
+
+  @Test
+  public void testReadFullySmallReads() throws Exception {
+    byte[] buffer = new byte[5];
+
+    MockInputStream stream = new MockInputStream(2, 3, 3);
+    IOUtil.readFully(stream, buffer, 0, buffer.length);
+
+    Assert.assertArrayEquals("Byte array contents should match",
+        Arrays.copyOfRange(MockInputStream.TEST_ARRAY, 0, 5), buffer);
+    Assert.assertEquals("Stream position should reflect bytes read", 5, stream.getPos());
+  }
+
+  @Test
+  public void testReadFullyJustRight() throws Exception {
+    final byte[] buffer = new byte[10];
+
+    final MockInputStream stream = new MockInputStream(2, 3, 3);
+    IOUtil.readFully(stream, buffer, 0, buffer.length);
+
+    Assert.assertArrayEquals("Byte array contents should match", MockInputStream.TEST_ARRAY, buffer);
+    Assert.assertEquals("Stream position should reflect bytes read", 10, stream.getPos());
+
+    AssertHelpers.assertThrows("Should throw EOFException if no more bytes left",
+        EOFException.class, () -> {
+          IOUtil.readFully(stream, buffer, 0, 1);
+          return null;
+        });
+  }
+
+  @Test
+  public void testReadFullyUnderflow() {
+    final byte[] buffer = new byte[11];
+
+    final MockInputStream stream = new MockInputStream(2, 3, 3);
+
+    AssertHelpers.assertThrows("Should throw EOFException if no more bytes left",
+        EOFException.class, () -> {
+          IOUtil.readFully(stream, buffer, 0, buffer.length);
+          return null;
+        });
+
+    Assert.assertArrayEquals("Should have consumed bytes",
+        MockInputStream.TEST_ARRAY, Arrays.copyOfRange(buffer, 0, 10));
+    Assert.assertEquals("Stream position should reflect bytes read", 10, stream.getPos());
+  }
+
+  @Test
+  public void testReadFullyStartAndLength() throws IOException {
+    byte[] buffer = new byte[10];
+
+    MockInputStream stream = new MockInputStream();
+    IOUtil.readFully(stream, buffer, 2, 5);
+
+    Assert.assertArrayEquals("Byte array contents should match",
+        Arrays.copyOfRange(MockInputStream.TEST_ARRAY, 0, 5), Arrays.copyOfRange(buffer, 2, 7));
+    Assert.assertEquals("Stream position should reflect bytes read", 5, stream.getPos());
+  }
+
+  @Test
+  public void testReadFullyZeroByteRead() throws IOException {
+    byte[] buffer = new byte[0];
+
+    MockInputStream stream = new MockInputStream();
+    IOUtil.readFully(stream, buffer, 0, buffer.length);
+
+    Assert.assertEquals("Stream position should reflect bytes read", 0, stream.getPos());
+  }
+
+  @Test
+  public void testReadFullySmallReadsWithStartAndLength() throws IOException {
+    byte[] buffer = new byte[10];
+
+    MockInputStream stream = new MockInputStream(2, 2, 3);
+    IOUtil.readFully(stream, buffer, 2, 5);
+
+    Assert.assertArrayEquals("Byte array contents should match",
+        Arrays.copyOfRange(MockInputStream.TEST_ARRAY, 0, 5), Arrays.copyOfRange(buffer, 2, 7));
+    Assert.assertEquals("Stream position should reflect bytes read", 5, stream.getPos());
+  }
+
+}

From a532db33067c7b6833ee954155225a9179a95024 Mon Sep 17 00:00:00 2001
From: Ryan Blue <blue@apache.org>
Date: Sun, 24 Apr 2022 09:50:25 -0700
Subject: [PATCH 13/15] Update LICENSE.

---
 LICENSE | 1 +
 1 file changed, 1 insertion(+)

diff --git a/LICENSE b/LICENSE
index 82a12b78272b..064892499911 100644
--- a/LICENSE
+++ b/LICENSE
@@ -228,6 +228,7 @@ This product includes code from Apache Parquet.
 * DynMethods.java
 * DynConstructors.java
 * AssertHelpers.java
+* IOUtil.java readFully and tests
 
 Copyright: 2014-2017 The Apache Software Foundation.
 Home page: https://parquet.apache.org/

From 3960e5b4eaf01c7d3523aa62f8810c36bf09b680 Mon Sep 17 00:00:00 2001
From: Daniel Weeks <dweeks@apache.org>
Date: Sun, 24 Apr 2022 14:40:14 -0700
Subject: [PATCH 14/15] Checkstyle

---
 core/src/test/java/org/apache/iceberg/io/MockInputStream.java | 1 +
 1 file changed, 1 insertion(+)

diff --git a/core/src/test/java/org/apache/iceberg/io/MockInputStream.java b/core/src/test/java/org/apache/iceberg/io/MockInputStream.java
index 03bdc2d97a06..d022728cb73f 100644
--- a/core/src/test/java/org/apache/iceberg/io/MockInputStream.java
+++ b/core/src/test/java/org/apache/iceberg/io/MockInputStream.java
@@ -27,6 +27,7 @@ class MockInputStream extends ByteArrayInputStream {
 
   private int[] lengths;
   private int current = 0;
+  
   MockInputStream(int... actualReadLengths) {
     super(TEST_ARRAY);
     this.lengths = actualReadLengths;

From 51c292ee45e8a570252d1124615c093a59fb2478 Mon Sep 17 00:00:00 2001
From: Ryan Blue <blue@apache.org>
Date: Sun, 24 Apr 2022 15:08:35 -0700
Subject: [PATCH 15/15] Remove trailing whitespace.

---
 core/src/test/java/org/apache/iceberg/io/MockInputStream.java | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/core/src/test/java/org/apache/iceberg/io/MockInputStream.java b/core/src/test/java/org/apache/iceberg/io/MockInputStream.java
index d022728cb73f..7cc251ebd641 100644
--- a/core/src/test/java/org/apache/iceberg/io/MockInputStream.java
+++ b/core/src/test/java/org/apache/iceberg/io/MockInputStream.java
@@ -27,7 +27,7 @@ class MockInputStream extends ByteArrayInputStream {
 
   private int[] lengths;
   private int current = 0;
-  
+
   MockInputStream(int... actualReadLengths) {
     super(TEST_ARRAY);
     this.lengths = actualReadLengths;