[SPARK-9156][SQL] codegen StringSplit

Jira: https://issues.apache.org/jira/browse/SPARK-9156

Author: Tarek Auel <tarek.auel@googlemail.com>

Closes #7547 from tarekauel/SPARK-9156 and squashes the following commits:

0be2700 [Tarek Auel] [SPARK-9156][SQL] indention fix
b860eaf [Tarek Auel] [SPARK-9156][SQL] codegen StringSplit
5ad6a1f [Tarek Auel] [SPARK-9156] codegen StringSplit

2 files changed, 20 insertions, 0 deletions

diff --git a/unsafe/src/main/java/org/apache/spark/unsafe/types/UTF8String.java b/unsafe/src/main/java/org/apache/spark/unsafe/types/UTF8String.java
index fc63fe537d..ed354f7f87 100644
--- a/unsafe/src/main/java/org/apache/spark/unsafe/types/UTF8String.java
+++ b/unsafe/src/main/java/org/apache/spark/unsafe/types/UTF8String.java
@@ -487,6 +487,15 @@ public final class UTF8String implements Comparable<UTF8String>, Serializable {
     return fromBytes(result);
   }
 
+  public UTF8String[] split(UTF8String pattern, int limit) {
+    String[] splits = toString().split(pattern.toString(), limit);
+    UTF8String[] res = new UTF8String[splits.length];
+    for (int i = 0; i < res.length; i++) {
+      res[i] = fromString(splits[i]);
+    }
+    return res;
+  }
+
   @Override
   public String toString() {
     try {
diff --git a/unsafe/src/test/java/org/apache/spark/unsafe/types/UTF8StringSuite.java b/unsafe/src/test/java/org/apache/spark/unsafe/types/UTF8StringSuite.java
index d730b1d138..1f5572c509 100644
--- a/unsafe/src/test/java/org/apache/spark/unsafe/types/UTF8StringSuite.java
+++ b/unsafe/src/test/java/org/apache/spark/unsafe/types/UTF8StringSuite.java
@@ -18,6 +18,7 @@
 package org.apache.spark.unsafe.types;
 
 import java.io.UnsupportedEncodingException;
+import java.util.Arrays;
 
 import org.junit.Test;
 
@@ -270,6 +271,16 @@ public class UTF8StringSuite {
       fromString("数据砖头孙行者孙行者孙行"),
       fromString("数据砖头").rpad(12, fromString("孙行者")));
   }
+
+  @Test
+  public void split() {
+    assertTrue(Arrays.equals(fromString("ab,def,ghi").split(fromString(","), -1),
+      new UTF8String[]{fromString("ab"), fromString("def"), fromString("ghi")}));
+    assertTrue(Arrays.equals(fromString("ab,def,ghi").split(fromString(","), 2),
+      new UTF8String[]{fromString("ab"), fromString("def,ghi")}));
+    assertTrue(Arrays.equals(fromString("ab,def,ghi").split(fromString(","), 2),
+      new UTF8String[]{fromString("ab"), fromString("def,ghi")}));
+  }
   
   @Test
   public void levenshteinDistance() {