Example usage for java.lang.reflect Array newInstance

Introduction

In this page you can find the example usage for java.lang.reflect Array newInstance.

Prototype

public static Object newInstance(Class<?> componentType, int... dimensions)
        throws IllegalArgumentException, NegativeArraySizeException

Source Link

Document

Creates a new array with the specified component type and dimensions.

Usage

From source file:Main.java

public static <T> Object convertListToArray(List<T> list, Class<T> destEntryType) {

    Object outArray = Array.newInstance(destEntryType, list.size());
    int count = 0;
    int size = list.size();
    for (int i = 0; i < size; i++) {
        Object element = list.get(i);
        Array.set(outArray, count, element);
        count++;/*from   ww w. j  a  v  a2  s .  c  om*/
    }
    if (destEntryType.isPrimitive())
        return outArray;
    else
        return (T[]) outArray;
}

From source file:Main.java

/**
 * Replace the value of a field containing a non null array, by a new array containing the elements of the original
 * array plus the elements of extraElements.
 *
 * @param instance the instance whose field is to be modified.
 * @param fieldName the field to modify.
 * @param extraElements elements to append at the end of the array.
 *///ww  w.  ja v a2  s. c  om
static void expandFieldArray(Object instance, String fieldName, Object[] extraElements)
        throws NoSuchFieldException, IllegalArgumentException, IllegalAccessException {
    Field jlrField = findField(instance, fieldName);
    Object[] original = (Object[]) jlrField.get(instance);
    Object[] combined = (Object[]) Array.newInstance(original.getClass().getComponentType(),
            original.length + extraElements.length);
    System.arraycopy(extraElements, 0, combined, 0, extraElements.length);
    System.arraycopy(original, 0, combined, extraElements.length, original.length);
    jlrField.set(instance, combined);
}

From source file:Main.java

@SuppressWarnings("unchecked")
public static final <T> T[] add(T[] array, T obj) {
    if (array == null) {
        throw new IllegalArgumentException("array");
    }//  www. j  av  a  2 s.c om
    T[] newArray = (T[]) Array.newInstance(array.getClass().getComponentType(), array.length + 1);
    System.arraycopy(array, 0, newArray, 0, array.length);
    newArray[array.length] = obj;
    return newArray;
}

From source file:Main.java

@SuppressWarnings("unchecked")
public static final <T> T[] remove(T[] array, T obj) {
    int index = indexOf(array, obj);
    if (index < 0) {
        return array;
    }/*from  w w  w.j  a  v  a2 s  .co m*/
    T[] newArray = (T[]) Array.newInstance(array.getClass().getComponentType(), array.length - 1);
    if (index > 0) {
        System.arraycopy(array, 0, newArray, 0, index);
    }
    if (index < array.length - 1) {
        System.arraycopy(array, index + 1, newArray, index, newArray.length - index);
    }
    return newArray;
}

From source file:Main.java

@SuppressWarnings("unchecked")
public static <E extends Object> E[] toArray(List<E> list, Class<E> clazz) {
    return list.toArray((E[]) Array.newInstance(clazz, list.size()));
}

From source file:Main.java

@SuppressWarnings("unchecked")
private static <E> E[] createArray(Class<E> elemType, int length) {
    return (E[]) Array.newInstance(elemType, length);
}

From source file:Main.java

/**
 * Remove all null element in the given array. Will return null if the array is null.
 *
 * @return A new array if any element is removed, or the origin array if nothing removed.
 *//*from   w  w w. j  av a 2 s .c  om*/
public static <T> T[] removeNull(T[] array) {
    if (array == null) {
        return null;
    }
    List<T> list = new ArrayList<T>();
    boolean changed = false;
    for (T element : array) {
        if (element != null) {
            list.add(element);
        } else {
            changed = true;
        }
    }
    if (!changed) {
        return array;
    } else {
        @SuppressWarnings({ "unchecked" })
        T[] newArray = (T[]) Array.newInstance(array.getClass().getComponentType(), list.size());
        return list.isEmpty() ? newArray : list.toArray(newArray);
    }
}

From source file:Main.java

public static Object expand(Object obj, int i, boolean flag) {
    int j = Array.getLength(obj);
    Object obj1 = Array.newInstance(obj.getClass().getComponentType(), j + i);
    System.arraycopy(obj, 0, obj1, flag ? 0 : i, j);
    return obj1;/*from ww  w.jav  a  2  s .  c  o m*/
}

From source file:Main.java

public static Object cut(Object obj, int size) {
    int j;/*from w  w w .j a  va2 s . c  om*/
    if ((j = Array.getLength(obj)) == 1) {
        return Array.newInstance(obj.getClass().getComponentType(), 0);
    }
    int k;
    if ((k = j - size - 1) > 0) {
        System.arraycopy(obj, size + 1, obj, size, k);
    }
    j--;
    Object obj1 = Array.newInstance(obj.getClass().getComponentType(), j);
    System.arraycopy(obj, 0, obj1, 0, j);
    return obj1;
}

From source file:Main.java

/**
 * Converts a collection into an array.//from  w ww  .j a  va2 s  .co  m
 * @param collection the collection to convert
 * @param clazz the class of the items in the collections
 * @return a non-null array
 */
public static <T> T[] convertToArray(Collection<T> collection, Class<T> clazz) {
    T[] result = (T[]) Array.newInstance(clazz, collection.size());
    return collection.toArray(result);
}