add array_equals function

Author: aaronshan

README.md

@@ -35,7 +35,7 @@ It will generate hive-third-functions-${version}-shaded.jar in target directory.
 
 You can also directly download file from [release page](https://github.com/aaronshan/hive-third-functions/releases).
 
-> current latest version is `2.2.0`
+> current latest version is `2.2.1`
 
 ## Functions
 
@@ -52,6 +52,7 @@ You can also directly download file from [release page](https://github.com/aaron
 | function| description |
 |:--|:--|
 |array_contains(array<E>, E) -> boolean | whether array contains value or not.|
+|array_equals(array<E>, array<E>) -> boolean | whether two array equals or not.|
 |array_intersect(array, array) -> array | returns the two array's intersection, without duplicates.|
 |array_max(array<E>) -> E | returns the maximum value of input array.|
 |array_min(array<E>) -> E | returns the minimum value of input array.|
@@ -146,6 +147,7 @@ Put these statements into `${HOME}/.hiverc` or exec its on hive cli env.
 ```
 add jar ${jar_location_dir}/hive-third-functions-${version}-shaded.jar
 create temporary function array_contains as 'cc.shanruifeng.functions.array.UDFArrayContains';
+create temporary function array_equals as 'cc.shanruifeng.functions.array.UDFArrayEquals';
 create temporary function array_intersect as 'cc.shanruifeng.functions.array.UDFArrayIntersect';
 create temporary function array_max as 'cc.shanruifeng.functions.array.UDFArrayMax';
 create temporary function array_min as 'cc.shanruifeng.functions.array.UDFArrayMin';
@@ -236,6 +238,7 @@ select zodiac_en('1989-01-08') => Capricorn
 
 ```
 select array_contains(array(16,12,18,9), 12) => true
+select array_equals(array(16,12,18,9), array(16,12,18,9)) => true
 select array_intersect(array(16,12,18,9,null), array(14,9,6,18,null)) => [null,9,18]
 select array_max(array(16,13,12,13,18,16,9,18)) => 18
 select array_min(array(16,12,18,9)) => 9

pom.xml

@@ -6,7 +6,7 @@
 
     <groupId>cc.shanruifeng</groupId>
     <artifactId>hive-third-functions</artifactId>
-    <version>2.2.0</version>
+    <version>2.2.1</version>
 
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>

src/main/java/cc/shanruifeng/functions/array/UDFArrayEquals.java

@@ -0,0 +1,99 @@
+package cc.shanruifeng.functions.array;
+
+import cc.shanruifeng.functions.utils.ArrayUtils;
+import org.apache.hadoop.hive.ql.exec.Description;
+import org.apache.hadoop.hive.ql.exec.UDFArgumentException;
+import org.apache.hadoop.hive.ql.exec.UDFArgumentLengthException;
+import org.apache.hadoop.hive.ql.exec.UDFArgumentTypeException;
+import org.apache.hadoop.hive.ql.metadata.HiveException;
+import org.apache.hadoop.hive.ql.udf.generic.GenericUDF;
+import org.apache.hadoop.hive.serde2.objectinspector.ListObjectInspector;
+import org.apache.hadoop.hive.serde2.objectinspector.ObjectInspector;
+import org.apache.hadoop.hive.serde2.objectinspector.ObjectInspectorUtils;
+import org.apache.hadoop.hive.serde2.objectinspector.primitive.PrimitiveObjectInspectorFactory;
+import org.apache.hadoop.io.BooleanWritable;
+
+/**
+ * @author ruifeng.shan
+ * @date 2016-09-08
+ * @time 16:03
+ */
+@Description(name = "array_equals"
+        , value = "_FUNC_(array, array) - whether two arrays equals or not."
+        , extended = "Example:\n > select _FUNC_(array, array) from src;")
+public class UDFArrayEquals extends GenericUDF {
+    private static final int ARG_COUNT = 2; // Number of arguments to this UDF
+    private transient ListObjectInspector leftArrayOI;
+    private transient ListObjectInspector rightArrayOI;
+    private transient ObjectInspector leftArrayElementOI;
+    private transient ObjectInspector rightArrayElementOI;
+
+    private BooleanWritable result;
+
+    public UDFArrayEquals() {
+    }
+
+    @Override
+    public ObjectInspector initialize(ObjectInspector[] arguments) throws UDFArgumentException {
+        // Check if two arguments were passed
+        if (arguments.length != ARG_COUNT) {
+            throw new UDFArgumentLengthException(
+                    "The function array_equals(array, array) takes exactly " + ARG_COUNT + " arguments.");
+        }
+
+        // Check if two argument is of category LIST
+        for (int i = 0; i < 2; i++) {
+            if (!arguments[i].getCategory().equals(ObjectInspector.Category.LIST)) {
+                throw new UDFArgumentTypeException(i,
+                        "\"" + org.apache.hadoop.hive.serde.serdeConstants.LIST_TYPE_NAME + "\" "
+                                + "expected at function array_equals, but "
+                                + "\"" + arguments[i].getTypeName() + "\" "
+                                + "is found");
+            }
+        }
+
+        leftArrayOI = (ListObjectInspector) arguments[0];
+        rightArrayOI = (ListObjectInspector) arguments[1];
+
+        leftArrayElementOI = leftArrayOI.getListElementObjectInspector();
+        rightArrayElementOI = rightArrayOI.getListElementObjectInspector();
+
+        // Check if two array are of same type
+        if (!ObjectInspectorUtils.compareTypes(leftArrayElementOI, rightArrayElementOI)) {
+            throw new UDFArgumentTypeException(1,
+                    "\"" + leftArrayElementOI.getTypeName() + "\""
+                            + " expected at function array_equals, but "
+                            + "\"" + rightArrayElementOI.getTypeName() + "\""
+                            + " is found");
+        }
+
+        // Check if the comparison is supported for this type
+        if (!ObjectInspectorUtils.compareSupported(leftArrayElementOI)) {
+            throw new UDFArgumentException("The function array_equals"
+                    + " does not support comparison for "
+                    + "\"" + leftArrayElementOI.getTypeName() + "\""
+                    + " types");
+        }
+
+        result = new BooleanWritable(false);
+        return PrimitiveObjectInspectorFactory.writableBooleanObjectInspector;
+    }
+
+    @Override
+    public Object evaluate(DeferredObject[] arguments) throws HiveException {
+        Object leftArray = arguments[0].get();
+        Object rightArray = arguments[1].get();
+
+        boolean ret = ArrayUtils.arrayEquals(leftArray, rightArray, leftArrayOI);
+        result.set(ret);
+
+        return result;
+    }
+
+    @Override
+    public String getDisplayString(String[] strings) {
+        assert (strings.length == ARG_COUNT);
+        return "array_equals(" + strings[0] + ", "
+                + strings[1] + ")";
+    }
+}

src/main/java/cc/shanruifeng/functions/utils/ArrayUtils.java

@@ -34,4 +34,32 @@ public int compare(int left, int right) {
             }
         };
     }
+
+    public static boolean arrayEquals(Object left, Object right, ListObjectInspector arrayOI) {
+        if (left == null || right == null) {
+            if (left == null && right == null) {
+                return true;
+            }
+            return false;
+        }
+
+        int leftArrayLength = arrayOI.getListLength(left);
+        int rightArrayLength = arrayOI.getListLength(right);
+
+        if (leftArrayLength != rightArrayLength) {
+            return false;
+        }
+
+        ObjectInspector arrayElementOI = arrayOI.getListElementObjectInspector();
+        for (int i = 0; i < leftArrayLength; i++) {
+            Object leftArrayElement = arrayOI.getListElement(left, i);
+            Object rightArrayElement = arrayOI.getListElement(right, i);
+            int compareValue = ObjectInspectorUtils.compare(leftArrayElement, arrayElementOI, rightArrayElement, arrayElementOI);
+            if (compareValue != 0) {
+                return false;
+            }
+        }
+
+        return true;
+    }
 }