add some more tests/utility code for row updates

git-svn-id: https://svn.code.sf.net/p/jackcess/code/jackcess/trunk@410 f203690c-595d-4dc9-a70b-905162fa7fd2

src/java/com/healthmarketscience/jackcess/Cursor.java

@@ -28,6 +28,7 @@ King of Prussia, PA 19406
 package com.healthmarketscience.jackcess;
 
 import java.io.IOException;
+import java.util.Arrays;
 import java.util.Collection;
 import java.util.Iterator;
 import java.util.LinkedHashMap;
@@ -884,6 +885,20 @@ public abstract class Cursor implements Iterable<Map<String, Object>>
     return _table.getRowValue(_rowState, _curPos.getRowId(), column);
   }
 
+  /**
+   * Updates a single value in the current row.
+   * @throws IllegalStateException if the current row is not valid (at
+   *         beginning or end of table), or deleted.
+   */
+  public void setCurrentRowValue(Column column, Object value)
+    throws IOException
+  {
+    Object[] row = new Object[_table.getColumnCount()];
+    Arrays.fill(row, Column.KEEP_VALUE);
+    row[column.getColumnIndex()] = value;
+    _table.updateRow(_rowState, _curPos.getRowId(), row);
+  }
+
   /**
    * Returns {@code true} if this cursor is up-to-date with respect to the
    * relevant table and related table objects, {@code false} otherwise.
@@ -902,8 +917,8 @@ public abstract class Cursor implements Iterable<Map<String, Object>>
    * Finds the next non-deleted row after the given row (as defined by this
    * cursor) and returns the id of the row, where "next" may be backwards if
    * moveForward is {@code false}.  If there are no more rows, the returned
-   * rowId should equal the value returned by {@link #getLastPosition} if moving
-   * forward and {@link #getFirstPosition} if moving backward.
+   * rowId should equal the value returned by {@link #getLastPosition} if
+   * moving forward and {@link #getFirstPosition} if moving backward.
    */
   protected abstract Position findAnotherPosition(RowState rowState,
                                                   Position curPos,

src/java/com/healthmarketscience/jackcess/Table.java

@@ -1151,6 +1151,24 @@ public class Table
     return row;
   }
   
+  /**
+   * Converts a map of columnName -> columnValue to an array of row values
+   * appropriate for a call to {@link #updateCurrentRow(Object...)}.
+   */
+  public Object[] asUpdateRow(Map<String,Object> rowMap) {
+    Object[] row = new Object[_columns.size()];
+    Arrays.fill(row, Column.KEEP_VALUE);
+    if(rowMap == null) {
+      return row;
+    }
+    for(Column col : _columns) {
+      if(rowMap.containsKey(col.getName())) {
+        row[col.getColumnIndex()] = rowMap.get(col.getName());
+      }
+    }
+    return row;
+  }
+  
   /**
    * Add a single row to this table and write it to disk
    * <p>

test/src/java/com/healthmarketscience/jackcess/DatabaseTest.java

@@ -160,7 +160,7 @@ public class DatabaseTest extends TestCase {
   }
   
   public void testGetColumns() throws Exception {
-    List columns = open().getTable("Table1").getColumns();
+    List<Column> columns = open().getTable("Table1").getColumns();
     assertEquals(9, columns.size());
     checkColumn(columns, 0, "A", DataType.TEXT);
     checkColumn(columns, 1, "B", DataType.TEXT);
@@ -173,11 +173,11 @@ public class DatabaseTest extends TestCase {
     checkColumn(columns, 8, "I", DataType.BOOLEAN);
   }
   
-  static void checkColumn(List columns, int columnNumber, String name,
+  static void checkColumn(List<Column> columns, int columnNumber, String name,
       DataType dataType)
     throws Exception
   {
-    Column column = (Column) columns.get(columnNumber);
+    Column column = columns.get(columnNumber);
     assertEquals(name, column.getName());
     assertEquals(dataType, column.getType());
   }
@@ -461,7 +461,7 @@ public class DatabaseTest extends TestCase {
     File bogusFile = new File("fooby-dooby.mdb");
     assertTrue(!bogusFile.exists());
     try {
-      Database db = open(bogusFile);
+      open(bogusFile);
       fail("FileNotFoundException should have been thrown");
     } catch(FileNotFoundException e) {
     }
@@ -930,46 +930,74 @@ public class DatabaseTest extends TestCase {
       t.addRow("row" + i, Column.AUTO_NUMBER, "initial data");
     }
 
-    t.reset();
-    t.getNextRow();
-    Map<String,Object> row = t.getNextRow();
+    Cursor c = Cursor.createCursor(t);
+    c.reset();
+    c.moveNextRows(2);
+    Map<String,Object> row = c.getCurrentRow();
 
     assertEquals(createExpectedRow("name", "row1", 
                                    "id", 2,
                                    "data", "initial data"),
                  row);
 
-    t.updateCurrentRow(Column.KEEP_VALUE, Column.AUTO_NUMBER, "new data");
+    c.updateCurrentRow(Column.KEEP_VALUE, Column.AUTO_NUMBER, "new data");
 
-    t.getNextRow();
-    t.getNextRow();
-    row = t.getNextRow();
+    c.moveNextRows(3);
+    row = c.getCurrentRow();
 
     assertEquals(createExpectedRow("name", "row4", 
                                    "id", 5,
                                    "data", "initial data"),
                  row);
 
-    t.updateCurrentRow(Column.KEEP_VALUE, Column.AUTO_NUMBER, "a larger amount of new data");
+    c.updateCurrentRow(Column.KEEP_VALUE, Column.AUTO_NUMBER, "a larger amount of new data");
 
-    t.reset();
-    t.getNextRow();
-    row = t.getNextRow();
+    c.reset();
+    c.moveNextRows(2);
+    row = c.getCurrentRow();
 
     assertEquals(createExpectedRow("name", "row1", 
                                    "id", 2,
                                    "data", "new data"),
                  row);
 
-    t.getNextRow();
-    t.getNextRow();
-    row = t.getNextRow();
+    c.moveNextRows(3);
+    row = c.getCurrentRow();
 
     assertEquals(createExpectedRow("name", "row4", 
                                    "id", 5,
                                    "data", "a larger amount of new data"),
                  row);
 
+    t.reset();
+    
+    String str = createString(100);
+    for(int i = 10; i < 50; ++i) {
+      t.addRow("row" + i, Column.AUTO_NUMBER, "big data_" + str);
+    }
+
+    c.reset();
+    c.moveNextRows(9);
+    row = c.getCurrentRow();
+
+    assertEquals(createExpectedRow("name", "row8", 
+                                   "id", 9,
+                                   "data", "initial data"),
+                 row);
+
+    String newText = "updated big data_" + createString(200);
+
+    c.setCurrentRowValue(t.getColumn("data"), newText);
+
+    c.reset();
+    c.moveNextRows(9);
+    row = c.getCurrentRow();
+
+    assertEquals(createExpectedRow("name", "row8", 
+                                   "id", 9,
+                                   "data", newText),
+                 row);
+
     db.close();
   }