[MINOR][BUILD] Fix Java linter errors

## What changes were proposed in this pull request?

This PR fixes the minor Java linter errors like the following.
```
-    public int read(char cbuf[], int off, int len) throws IOException {
+    public int read(char[] cbuf, int off, int len) throws IOException {
```

## How was this patch tested?

Manual.
```
$ build/mvn -T 4 -q -DskipTests -Pyarn -Phadoop-2.3 -Pkinesis-asl -Phive -Phive-thriftserver install
$ dev/lint-java
Using `mvn` from path: /usr/local/bin/mvn
Checkstyle checks passed.
```

Author: Dongjoon Hyun <dongjoon@apache.org>

Closes #14017 from dongjoon-hyun/minor_build_java_linter_error.

2 files changed, 13 insertions, 10 deletions

diff --git a/sql/catalyst/src/main/java/org/apache/spark/sql/catalyst/expressions/xml/UDFXPathUtil.java b/sql/catalyst/src/main/java/org/apache/spark/sql/catalyst/expressions/xml/UDFXPathUtil.java
index 01a11f9bdc..410e9e51ba 100644
--- a/sql/catalyst/src/main/java/org/apache/spark/sql/catalyst/expressions/xml/UDFXPathUtil.java
+++ b/sql/catalyst/src/main/java/org/apache/spark/sql/catalyst/expressions/xml/UDFXPathUtil.java
@@ -19,7 +19,6 @@ package org.apache.spark.sql.catalyst.expressions.xml;
 
 import java.io.IOException;
 import java.io.Reader;
-import java.io.StringReader;
 
 import javax.xml.namespace.QName;
 import javax.xml.xpath.XPath;
@@ -71,7 +70,7 @@ public class UDFXPathUtil {
     try {
       return expression.evaluate(inputSource, qname);
     } catch (XPathExpressionException e) {
-      throw new RuntimeException ("Invalid expression '" + oldPath + "'", e);
+      throw new RuntimeException("Invalid expression '" + oldPath + "'", e);
     }
   }
 
@@ -96,7 +95,7 @@ public class UDFXPathUtil {
   }
 
   /**
-   * Reusable, non-threadsafe version of {@link StringReader}.
+   * Reusable, non-threadsafe version of {@link java.io.StringReader}.
    */
   public static class ReusableStringReader extends Reader {
 
@@ -117,20 +116,22 @@ public class UDFXPathUtil {
 
     /** Check to make sure that the stream has not been closed */
     private void ensureOpen() throws IOException {
-      if (str == null)
+      if (str == null) {
         throw new IOException("Stream closed");
+      }
     }
 
     @Override
     public int read() throws IOException {
       ensureOpen();
-      if (next >= length)
+      if (next >= length) {
         return -1;
+      }
       return str.charAt(next++);
     }
 
     @Override
-    public int read(char cbuf[], int off, int len) throws IOException {
+    public int read(char[] cbuf, int off, int len) throws IOException {
       ensureOpen();
       if ((off < 0) || (off > cbuf.length) || (len < 0)
         || ((off + len) > cbuf.length) || ((off + len) < 0)) {
@@ -138,8 +139,9 @@ public class UDFXPathUtil {
       } else if (len == 0) {
         return 0;
       }
-      if (next >= length)
+      if (next >= length) {
         return -1;
+      }
       int n = Math.min(length - next, len);
       str.getChars(next, next + n, cbuf, off);
       next += n;
@@ -149,8 +151,9 @@ public class UDFXPathUtil {
     @Override
     public long skip(long ns) throws IOException {
       ensureOpen();
-      if (next >= length)
+      if (next >= length) {
         return 0;
+      }
       // Bound skip by beginning and end of the source
       long n = Math.min(length - next, ns);
       n = Math.max(-next, n);
diff --git a/sql/catalyst/src/main/java/org/apache/spark/sql/execution/UnsafeExternalRowSorter.java b/sql/catalyst/src/main/java/org/apache/spark/sql/execution/UnsafeExternalRowSorter.java
index b4e87c3035..c29b002a99 100644
--- a/sql/catalyst/src/main/java/org/apache/spark/sql/execution/UnsafeExternalRowSorter.java
+++ b/sql/catalyst/src/main/java/org/apache/spark/sql/execution/UnsafeExternalRowSorter.java
@@ -89,8 +89,8 @@ public final class UnsafeExternalRowSorter {
       sparkEnv.conf().getInt("spark.shuffle.sort.initialBufferSize",
                              DEFAULT_INITIAL_SORT_BUFFER_SIZE),
       pageSizeBytes,
-      SparkEnv.get().conf().getLong("spark.shuffle.spill.numElementsForceSpillThreshold", UnsafeExternalSorter
-          .DEFAULT_NUM_ELEMENTS_FOR_SPILL_THRESHOLD),
+      SparkEnv.get().conf().getLong("spark.shuffle.spill.numElementsForceSpillThreshold",
+        UnsafeExternalSorter.DEFAULT_NUM_ELEMENTS_FOR_SPILL_THRESHOLD),
       canUseRadixSort
     );
   }