Add | Implement hashCode() and equals() APIs for SQLServerDataTable a…

…nd SQLServerDataColumn (#1146)

* Add | Add hashCode()/equals() methods to SQLServerDataColumn and SQLServerDataTable

src/main/java/com/microsoft/sqlserver/jdbc/SQLServerDataColumn.java

@@ -45,4 +45,35 @@ public String getColumnName() {
     public int getColumnType() {
         return javaSqlType;
     }
+
+    @Override
+    public int hashCode() {
+        int hash = 7;
+        hash = 31 * hash + javaSqlType;
+        hash = 31 * hash + precision;
+        hash = 31 * hash + scale;
+        hash = 31 * hash + numberOfDigitsIntegerPart;
+        hash = 31 * hash + (null != columnName ? columnName.hashCode() : 0);
+        return hash;
+    }
+
+    @Override
+    public boolean equals(Object object) {
+        if (this == object) {
+            return true;
+        }
+
+        if (null != object && object.getClass() == SQLServerDataColumn.class) {
+            SQLServerDataColumn aSQLServerDataColumn = (SQLServerDataColumn) object;
+            if (hashCode() == aSQLServerDataColumn.hashCode()) {
+                // Compare objects to avoid collision
+                return ((null == columnName && null == aSQLServerDataColumn.columnName
+                        || columnName.equals(aSQLServerDataColumn.columnName))
+                        && javaSqlType == aSQLServerDataColumn.javaSqlType
+                        && numberOfDigitsIntegerPart == aSQLServerDataColumn.numberOfDigitsIntegerPart
+                        && precision == aSQLServerDataColumn.precision && scale == aSQLServerDataColumn.scale);
+            }
+        }
+        return false;
+    }
 }

src/main/java/com/microsoft/sqlserver/jdbc/SQLServerDataTable.java

@@ -9,6 +9,7 @@
 import java.text.MessageFormat;
 import java.time.OffsetDateTime;
 import java.time.OffsetTime;
+import java.util.Arrays;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.Iterator;
@@ -334,4 +335,79 @@ public String getTvpName() {
     public void setTvpName(String tvpName) {
         this.tvpName = tvpName;
     }
+
+    @Override
+    public int hashCode() {
+        int hash = 7;
+        hash = 31 * hash + rowCount;
+        hash = 31 * hash + columnCount;
+        hash = 31 * hash + (null != columnMetadata ? columnMetadata.hashCode() : 0);
+        hash = 31 * hash + (null != columnNames ? columnNames.hashCode() : 0);
+        hash = 31 * hash + getRowsHashCode();
+        hash = 31 * hash + (null != tvpName ? tvpName.hashCode() : 0);
+        return hash;
+    }
+
+    @Override
+    public boolean equals(Object object) {
+        if (this == object) {
+            return true;
+        }
+
+        if (null != object && object.getClass() == SQLServerDataTable.class) {
+            SQLServerDataTable aSQLServerDataTable = (SQLServerDataTable) object;
+            if (hashCode() == aSQLServerDataTable.hashCode()) {
+
+                // Compare objects to avoid collision
+                boolean equalColumnMetadata = columnMetadata.equals(aSQLServerDataTable.columnMetadata);
+                boolean equalColumnNames = columnNames.equals(aSQLServerDataTable.columnNames);
+                boolean equalRowData = compareRows(aSQLServerDataTable.rows);
+
+                return (rowCount == aSQLServerDataTable.rowCount && columnCount == aSQLServerDataTable.columnCount
+                        && tvpName == aSQLServerDataTable.tvpName && equalColumnMetadata && equalColumnNames
+                        && equalRowData);
+            }
+        }
+        return false;
+    }
+
+    private int getRowsHashCode() {
+        if (null == rows) {
+            return 0;
+        }
+        int h = 0;
+        for (Entry<Integer, Object[]> entry : rows.entrySet()) {
+            h += entry.getKey() ^ Arrays.hashCode(entry.getValue());
+        }
+        return h;
+    }
+
+    private boolean compareRows(Map<Integer, Object[]> otherRows) {
+        if (rows == otherRows) {
+            return true;
+        }
+        if (rows.size() != otherRows.size()) {
+            return false;
+        }
+        try {
+            for (Entry<Integer, Object[]> e : rows.entrySet()) {
+                Integer key = e.getKey();
+                Object[] value = e.getValue();
+                if (null == value) {
+                    if (!(null == otherRows.get(key) && otherRows.containsKey(key))) {
+                        return false;
+                    }
+                } else {
+                    if (!Arrays.equals(value, otherRows.get(key))) {
+                        return false;
+                    }
+                }
+            }
+        } catch (ClassCastException unused) {
+            return false;
+        } catch (NullPointerException unused) {
+            return false;
+        }
+        return true;
+    }
 }

src/test/java/com/microsoft/sqlserver/jdbc/tvp/SQLServerDataTableTest.java

@@ -0,0 +1,103 @@
+/*
+ * Microsoft JDBC Driver for SQL Server Copyright(c) Microsoft Corporation All rights reserved. This program is made
+ * available under the terms of the MIT License. See the LICENSE file in the project root for more information.
+ */
+
+package com.microsoft.sqlserver.jdbc.tvp;
+
+import static org.junit.Assert.assertEquals;
+
+import java.math.BigDecimal;
+import java.sql.Types;
+import org.junit.jupiter.api.Test;
+import org.junit.platform.runner.JUnitPlatform;
+import org.junit.runner.RunWith;
+
+import com.microsoft.sqlserver.jdbc.SQLServerDataColumn;
+import com.microsoft.sqlserver.jdbc.SQLServerDataTable;
+import com.microsoft.sqlserver.jdbc.SQLServerException;
+
+
+@RunWith(JUnitPlatform.class)
+public class SQLServerDataTableTest {
+
+    @Test
+    public void testClear() throws SQLServerException {
+        SQLServerDataTable table = new SQLServerDataTable();
+        SQLServerDataColumn a = new SQLServerDataColumn("foo", Types.VARCHAR);
+        SQLServerDataColumn b = new SQLServerDataColumn("bar", Types.INTEGER);
+
+        table.addColumnMetadata(a);
+        table.addColumnMetadata(b);
+        assertEquals(2, table.getColumnMetadata().size());
+
+        table.clear();
+        assertEquals(0, table.getColumnMetadata().size());
+
+        table.addColumnMetadata(a);
+        table.addColumnMetadata(b);
+        assertEquals(2, table.getColumnMetadata().size());
+    }
+
+    @Test
+    public void testHashCodes() throws SQLServerException {
+        // Test Null field values for SQLServerDataColumn
+        SQLServerDataColumn nullDataColumn1 = new SQLServerDataColumn(null, 0);
+        SQLServerDataColumn nullDataColumn2 = new SQLServerDataColumn(null, 0);
+        assert (nullDataColumn1.hashCode() == nullDataColumn2.hashCode());
+        assert (nullDataColumn1.equals(nullDataColumn2));
+
+        // Test Null field values for SQLServerDataTable
+        SQLServerDataTable nullDataTable1 = new SQLServerDataTable();
+        SQLServerDataTable nullDataTable2 = new SQLServerDataTable();
+        assert (nullDataTable1.hashCode() == nullDataTable2.hashCode());
+        assert (nullDataTable1.equals(nullDataTable2));
+
+        SQLServerDataColumn a = new SQLServerDataColumn("foo", Types.VARCHAR);
+
+        // Test consistent generation of hashCode
+        assert (a.hashCode() == a.hashCode());
+        assert (a.equals(a));
+
+        SQLServerDataColumn aClone = new SQLServerDataColumn("foo", Types.VARCHAR);
+
+        // Test for different instances generating same hashCode for same data
+        assert (a.hashCode() == aClone.hashCode());
+        assert (a.equals(aClone));
+
+        SQLServerDataColumn b = new SQLServerDataColumn("bar", Types.DECIMAL);
+        SQLServerDataTable table = createTable(a, b);
+
+        // Test consistent generation of hashCode
+        assert (table.hashCode() == table.hashCode());
+        assert (table.equals(table));
+
+        SQLServerDataTable tableClone = createTable(aClone, b);
+
+        // Test for different instances generating same hashCode for same data
+        assert (table.hashCode() == tableClone.hashCode());
+        assert (table.equals(tableClone));
+
+        // Test for non equal hashCodes
+        assert (a.hashCode() != b.hashCode());
+        assert (!a.equals(b));
+
+        SQLServerDataColumn c = new SQLServerDataColumn("bar", Types.FLOAT);
+        table.clear();
+        table = createTable(a, c);
+
+        // Test for non equal hashCodes
+        assert (table.hashCode() != tableClone.hashCode());
+        assert (!table.equals(tableClone));
+    }
+
+    private SQLServerDataTable createTable(SQLServerDataColumn a, SQLServerDataColumn b) throws SQLServerException {
+        SQLServerDataTable table = new SQLServerDataTable();
+        table.addColumnMetadata(a);
+        table.addColumnMetadata(b);
+        table.addRow("Hello", new BigDecimal(1.5));
+        table.addRow("World", new BigDecimal(5.5));
+        table.setTvpName("TVP_HashCode");
+        return table;
+    }
+}