Java IDataCursor.first方法代码示例

import com.wm.data.IDataCursor; //导入方法依赖的package包/类
public final void remove(RemoveEntryOption removeOption) {
	Preconditions.checkNotNull(removeOption, "Remove option cannot be null");
	
	IDataCursorResource cursorRes = newCursorResource();

	try {
		IDataCursor cursor = cursorRes.getCursor();

		boolean exists = cursor.first(getKey());

		if (!exists && RemoveEntryOption.STRICT.equals(removeOption)) {
				throw new InexistentEntryException(
						"Entry with key '" + getKey() + "' doesn't exist and can't be removed");
		}
		deleteCurrentEntry(cursor);
	} finally {
		cursorRes.close();
	}
}
 

import com.wm.data.IDataCursor; //导入方法依赖的package包/类
public Collection<String> getKeys() {

		// Using LinkedHashSet to preserve insertion order
		Set<String> keys = new LinkedHashSet<String>();
		
		IDataCursorResource cursorRes = newCursorResource();
		try {
			IDataCursor cursor = cursorRes.getCursor();
			boolean hasMore = cursor.first();
			while (hasMore) {
				keys.add(cursor.getKey());

				hasMore = cursor.next();
			}
			return Collections.unmodifiableSet(keys);
		}
		finally {
			cursorRes.close();
		}
	}
 

import com.wm.data.IDataCursor; //导入方法依赖的package包/类
@Test
public void testPut() {
	List<String> list = Lists.newArrayList("Hello", "World");
	
	Document doc = docFactory.create();
	doc.stringsSplitEntry("words").put(list);
	IData iData = doc.getIData();
	
	IDataCursor cursor = iData.getCursor();
	
	assertEquals(2, IDataUtil.size(cursor));
	cursor.first();
	assertEquals("words", cursor.getKey());
	assertEquals("Hello", cursor.getValue());
	
	cursor.next();
	assertEquals("words", cursor.getKey());
	assertEquals("World", cursor.getValue());
	
}
 

import com.wm.data.IDataCursor; //导入方法依赖的package包/类
/**
 * Removes all key value pairs from the given IData document except those with a specified key.
 *
 * @param document          An IData document to be cleared.
 * @param keysToBePreserved List of simple or fully-qualified keys identifying items that should not be removed.
 */
public static void clear(IData document, String... keysToBePreserved) {
    if (document == null) return;

    IData saved = IDataFactory.create();
    if (keysToBePreserved != null) {
        for (String key : keysToBePreserved) {
            if (key != null) put(saved, key, get(document, key), false, false);
        }
    }

    IDataCursor cursor = document.getCursor();
    cursor.first();
    while (cursor.delete());
    cursor.destroy();

    if (keysToBePreserved != null) IDataUtil.merge(saved, document);
}
 

import com.wm.data.IDataCursor; //导入方法依赖的package包/类
/**
 * Removes the given key and its associated value from the given cursor.
 *
 * @param cursor    The cursor to remove the key from.
 * @param key       The key to be removed.
 * @param required  Throws an exception if true and a non-null value is not associated with the given key.
 * @return          The value that was associated with the key.
 */
public static Object remove(IDataCursor cursor, String key, boolean required) {
    if (cursor == null || key == null) return null;

    Object value = null;

    if (cursor.first(key)) {
        value = cursor.getValue();
        cursor.delete();
    }

    if (value == null && required) {
        throw new RuntimeException(new NoSuchFieldException(MessageFormat.format("Key \"{0}\" either does not exist or is associated with a null value", key)));
    }

    return value;
}
 

import com.wm.data.IDataCursor; //导入方法依赖的package包/类
/**
 * Returns the value associated with the given key from the IDataCursor.
 *
 * @param cursor        The IDataCursor to add the key value association to.
 * @param required      Throws an exception if true and a value is not associated with any of the given keys.
 * @param keys          One or more keys in order of precedence.
 * @return              The first value found associated with a given key.
 */
public static Object get(IDataCursor cursor, boolean required, String... keys) {
    if (cursor == null || keys == null || keys.length == 0 || keys[0] == null) return null;

    Object value = null;

    for (String key : keys) {
        if (key != null) {
            if (cursor.first(key)) {
                value = cursor.getValue();
            }
            if (value != null) break;
        }
    }

    if (value == null && required) {
        if (keys.length == 1) {
            throw new RuntimeException(new NoSuchFieldException(MessageFormat.format("Specified key does not exist or is associated with null value: {0}", keys[0])));
        } else {
            throw new RuntimeException(new NoSuchFieldException(MessageFormat.format("Specified keys do not exist or are associated with null values: {0}", ArrayHelper.join(keys, Sanitization.REMOVE_NULLS))));
        }
    }

    return value;
}
 

import com.wm.data.IDataCursor; //导入方法依赖的package包/类
@Test
public void add() throws Exception {
    String bandName = "Joy Division";

    ElementList<String, Object> band = new CaseInsensitiveElementList<Object>();
    band.add(new Element<String, Object>("Name", bandName));

    IDataCursor cursor = band.getCursor();
    assertEquals("Keys should be case insensitive", bandName, IDataUtil.getString(cursor, "name"));
    assertEquals("Keys should be case insensitive", bandName, IDataUtil.getString(cursor, "NAME"));
    assertEquals("Keys should be case insensitive", bandName, IDataUtil.getString(cursor, "naME"));

    cursor.first();
    assertEquals("Keys should have their case preserved", "Name", cursor.getKey());
    assertEquals(bandName, cursor.getValue());
}
 

import com.wm.data.IDataCursor; //导入方法依赖的package包/类
private void doPut(Iterable<?> values) {

		IDataCursorResource cursorRes = newCursorResource();
		try {
			IDataCursor cursor = cursorRes.getCursor();

			boolean continueLoop;

			/* Remove previous entries */
			do {
				boolean hasValWithKey = cursor.first(getKey());

				if (hasValWithKey) {
					continueLoop = cursor.delete();
				} else {
					continueLoop = false;
				}
			} while (continueLoop);

			cursor.last();

			for (Object individualVal : values) {
				Object normalisedIndividualVal = convertAndNormaliseValForPut(individualVal, mutatorType);
				cursor.insertAfter(getKey(), normalisedIndividualVal);
			}
		} finally {
			cursorRes.close();
		}
	}
 

import com.wm.data.IDataCursor; //导入方法依赖的package包/类
@Override
public final void remove(RemoveEntryOption removeOption) {
	Preconditions.checkNotNull(removeOption, "Remove option cannot be null");
	boolean hasMore;

	IDataCursorResource cursorRes = newCursorResource();
	try {

		IDataCursor cursor = cursorRes.getCursor();

		boolean hasFirst = cursor.first(getKey());

		if (!hasFirst && RemoveEntryOption.STRICT.equals(removeOption)) {
			throw new InexistentEntryException(
					"Entry with key '" + getKey() + "' doesn't exist and can't be removed");
		}

		hasMore = hasFirst;

		while (hasMore) {
			deleteCurrentEntry(cursor);

			hasMore = cursor.first(getKey());
		}
	} finally {
		cursorRes.close();
	}

}
 

import com.wm.data.IDataCursor; //导入方法依赖的package包/类
@Test
public void testRemove() {
	IData iData = IDataFactory.create();
	{
	IDataCursor cursor = iData.getCursor();
	cursor.insertAfter("first", "A");
	cursor.insertAfter("words", "Word to replace");
	cursor.insertAfter("middle", "M");
	cursor.insertAfter("words", "Another word to replace");
	cursor.insertAfter("last", "Z");
	}
	Document doc = docFactory.wrap(iData);
	doc.stringsSplitEntry("words").remove();
	
	IDataCursor cursor2 = doc.getIData().getCursor();
	
	assertEquals(3, IDataUtil.size(cursor2));
	cursor2.first();
	assertEquals("first", cursor2.getKey());
	assertEquals("A", cursor2.getValue());
	
	cursor2.next();
	assertEquals("middle", cursor2.getKey());
	assertEquals("M", cursor2.getValue());
	
	cursor2.next();
	assertEquals("last", cursor2.getKey());
	assertEquals("Z", cursor2.getValue());
	
}
 

import com.wm.data.IDataCursor; //导入方法依赖的package包/类
/**
 * Removes the value with the given key from the given IData document.
 *
 * @param document An IData document.
 * @param key      A simple or fully-qualified key identifying the value to be removed from the given IData
 *                 document.
 * @param literal  If true, the key will be treated as a literal key, rather than potentially as a fully-qualified
 *                 key.
 * @return         The given IData document.
 */
public static IData drop(IData document, String key, boolean literal) {
    if (document != null && key != null) {
        IDataCursor cursor = document.getCursor();

        if (cursor.first(key)) {
            cursor.delete();
        } else if (IDataKey.isFullyQualified(key, literal)) {
            drop(document, IDataKey.of(key, literal));
        }

        cursor.destroy();
    }
    return document;
}
 

import com.wm.data.IDataCursor; //导入方法依赖的package包/类
@Test
public void testPutInOrder() {
	List<String> list = Lists.newArrayList("Keep", "Me", "In", "Order");
	
	IData iData = IDataFactory.create();
	{
	IDataCursor cursor = iData.getCursor();
	cursor.insertAfter("first", "A");
	cursor.insertAfter("words", "Word to replace");
	cursor.insertAfter("middle", "M");
	cursor.insertAfter("words", "Another word to replace");
	cursor.insertAfter("last", "Z");
	}
	Document doc = docFactory.wrap(iData);
	doc.stringsSplitEntry("words").put(list);
	
	IDataCursor cursor2 = doc.getIData().getCursor();
	
	assertEquals(3+4, IDataUtil.size(cursor2));
	cursor2.first();
	assertEquals("first", cursor2.getKey());
	assertEquals("A", cursor2.getValue());
	
	cursor2.next();
	assertEquals("middle", cursor2.getKey());
	assertEquals("M", cursor2.getValue());
	
	cursor2.next();
	assertEquals("last", cursor2.getKey());
	assertEquals("Z", cursor2.getValue());
	
	cursor2.next();
	assertEquals("words", cursor2.getKey());
	assertEquals("Keep", cursor2.getValue());
	
	cursor2.next();
	assertEquals("words", cursor2.getKey());
	assertEquals("Me", cursor2.getValue());
	
	cursor2.next();
	assertEquals("words", cursor2.getKey());
	assertEquals("In", cursor2.getValue());
	
	cursor2.next();
	assertEquals("words", cursor2.getKey());
	assertEquals("Order", cursor2.getValue());
	
}
 

import com.wm.data.IDataCursor; //导入方法依赖的package包/类
@Test
public void testPutConvertedInOrder() {
	List<Integer> list = Lists.newArrayList(4, 3, 2, 1);
	
	IData iData = IDataFactory.create();
	{
	IDataCursor cursor = iData.getCursor();
	cursor.insertAfter("first", "A");
	cursor.insertAfter("numbers", "8");
	cursor.insertAfter("middle", "M");
	cursor.insertAfter("numbers", "9");
	cursor.insertAfter("last", "Z");
	}
	Document doc = docFactory.wrap(iData);
	doc.stringsSplitEntry("numbers").putConverted(list);
	
	IDataCursor cursor2 = doc.getIData().getCursor();
	
	assertEquals(3+4, IDataUtil.size(cursor2));
	cursor2.first();
	assertEquals("first", cursor2.getKey());
	assertEquals("A", cursor2.getValue());
	
	cursor2.next();
	assertEquals("middle", cursor2.getKey());
	assertEquals("M", cursor2.getValue());
	
	cursor2.next();
	assertEquals("last", cursor2.getKey());
	assertEquals("Z", cursor2.getValue());
	
	cursor2.next();
	assertEquals("numbers", cursor2.getKey());
	assertEquals("4", cursor2.getValue());
	
	cursor2.next();
	assertEquals("numbers", cursor2.getKey());
	assertEquals("3", cursor2.getValue());
	
	cursor2.next();
	assertEquals("numbers", cursor2.getKey());
	assertEquals("2", cursor2.getValue());
	
	cursor2.next();
	assertEquals("numbers", cursor2.getKey());
	assertEquals("1", cursor2.getValue());
	
}
 

import com.wm.data.IDataCursor; //导入方法依赖的package包/类
/**
 * Sorts the given IData document by its keys in natural ascending or descending order.
 *
 * @param document      An IData document to be sorted by its keys.
 * @param recurse       A boolean which when true will also recursively sort nested IData document and IData[]
 *                      document lists.
 * @param descending    Whether to sort in descending or ascending order.
 * @return              A new IData document which is duplicate of the given input IData document but with its keys
 *                      sorted in natural ascending order.
 */
public static IData sort(IData document, boolean recurse, boolean descending) {
    if (document == null) return null;

    String[] keys = ArrayHelper.sort(getKeys(document), descending);

    IData output = IDataFactory.create();
    IDataCursor ic = document.getCursor();
    IDataCursor oc = output.getCursor();

    for (int i = 0; i < keys.length; i++) {
        boolean result;

        if (i > 0 && keys[i].equals(keys[i - 1])) {
            result = ic.next(keys[i]);
        } else {
            result = ic.first(keys[i]);
        }

        if (result) {
            Object value = ic.getValue();
            if (recurse) {
                if (value instanceof IData[] || value instanceof Table || value instanceof IDataCodable[] || value instanceof IDataPortable[] || value instanceof ValuesCodable[]) {
                    IData[] array = toIDataArray(value);
                    for (int j = 0; j < array.length; j++) {
                        array[j] = sort(array[j], recurse);
                    }
                    value = array;
                } else if (value instanceof IData || value instanceof IDataCodable || value instanceof IDataPortable || value instanceof ValuesCodable) {
                    value = sort(toIData(value), recurse);
                }
            }
            oc.insertAfter(keys[i], value);
        }
    }

    ic.destroy();
    oc.destroy();

    return output;
}
 

import com.wm.data.IDataCursor; //导入方法依赖的package包/类
/**
 * Associates the given key with the given value in an IDataCursor.
 *
 * @param cursor            The IDataCursor to add the key value association to.
 * @param key               The key literal to be added.
 * @param value             The value to be associated with the given key. If null, no change is made to the cursor.
 * @param includeNullValue  If false and the given value is null, no change is made to the cursor. In all other
 *                          cases the given value will be associated with the given key.
 * @param includeEmptyValue If false and the given value is an empty array or empty string, no change is made to the
 *                          cursor. In all other cases the given value will be associated with the given key.
 * @param replace           If a value is already associated with the given key, replace it, rather than add a new
 *                          instance of the key.
 */
public static void put(IDataCursor cursor, String key, Object value, boolean includeNullValue, boolean includeEmptyValue, boolean replace) {
    if (!includeNullValue && value == null) return;
    if (!includeEmptyValue && ObjectHelper.isEmpty(value)) return;

    if (replace && cursor.first(key)) {
        cursor.setValue(value);
    } else {
        cursor.insertAfter(key, value);
    }
}