Hibernate example source code file (ArrayHelper.java)

This example Hibernate source code file (ArrayHelper.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Hibernate tags/keywords

arraylist, list, lockmode, lockoptions, object, object, reflection, seed, seed, string, string, stringbuffer, t, t, type, util

The Hibernate ArrayHelper.java source code

/*
 * Hibernate, Relational Persistence for Idiomatic Java
 *
 * Copyright (c) 2008, Red Hat Middleware LLC or third-party contributors as
 * indicated by the @author tags or express copyright attribution
 * statements applied by the authors.  All third-party contributions are
 * distributed under license by Red Hat Middleware LLC.
 *
 * This copyrighted material is made available to anyone wishing to use, modify,
 * copy, or redistribute it subject to the terms and conditions of the GNU
 * Lesser General Public License, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
 * for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this distribution; if not, write to:
 * Free Software Foundation, Inc.
 * 51 Franklin Street, Fifth Floor
 * Boston, MA  02110-1301  USA
 *
 */
package org.hibernate.internal.util.collections;

import java.lang.reflect.Array;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;

import org.hibernate.LockMode;
import org.hibernate.LockOptions;
import org.hibernate.type.Type;

public final class ArrayHelper {
	
	/*public static boolean contains(Object[] array, Object object) {
		for ( int i=0; i<array.length; i++ ) {
			if ( array[i].equals(object) ) return true;
		}
		return false;
	}*/
	
	public static int indexOf(Object[] array, Object object) {
		for ( int i=0; i<array.length; i++ ) {
			if ( array[i].equals(object) ) return i;
		}
		return -1;
	}
	
	/*public static Object[] clone(Class elementClass, Object[] array) {
		Object[] result = (Object[]) Array.newInstance( elementClass, array.length );
		System.arraycopy(array, 0, result, 0, array.length);
		return result;
	}*/

	public static String[] toStringArray(Object[] objects) {
		int length=objects.length;
		String[] result = new String[length];
		for (int i=0; i<length; i++) {
			result[i] = objects[i].toString();
		}
		return result;
	}

	public static String[] fillArray(String value, int length) {
		String[] result = new String[length];
		Arrays.fill(result, value);
		return result;
	}

	public static int[] fillArray(int value, int length) {
		int[] result = new int[length];
		Arrays.fill(result, value);
		return result;
	}

	public static LockMode[] fillArray(LockMode lockMode, int length) {
		LockMode[] array = new LockMode[length];
		Arrays.fill(array, lockMode);
		return array;
	}

	public static LockOptions[] fillArray(LockOptions lockOptions, int length) {
		LockOptions[] array = new LockOptions[length];
		Arrays.fill(array, lockOptions);
		return array;
	}

	public static String[] toStringArray(Collection coll) {
		return (String[]) coll.toArray( new String[coll.size()] );
	}
	
	public static String[][] to2DStringArray(Collection coll) {
		return (String[][]) coll.toArray( new String[ coll.size() ][] );
	}
	
	public static int[][] to2DIntArray(Collection coll) {
		return (int[][]) coll.toArray( new int[ coll.size() ][] );
	}
	
	public static Type[] toTypeArray(Collection coll) {
		return (Type[]) coll.toArray( new Type[coll.size()] );
	}

	public static int[] toIntArray(Collection coll) {
		Iterator iter = coll.iterator();
		int[] arr = new int[ coll.size() ];
		int i=0;
		while( iter.hasNext() ) {
			arr[i++] = ( (Integer) iter.next() ).intValue();
		}
		return arr;
	}

	public static boolean[] toBooleanArray(Collection coll) {
		Iterator iter = coll.iterator();
		boolean[] arr = new boolean[ coll.size() ];
		int i=0;
		while( iter.hasNext() ) {
			arr[i++] = ( (Boolean) iter.next() ).booleanValue();
		}
		return arr;
	}

	public static Object[] typecast(Object[] array, Object[] to) {
		return java.util.Arrays.asList(array).toArray(to);
	}

	//Arrays.asList doesn't do primitive arrays
	public static List toList(Object array) {
		if ( array instanceof Object[] ) return Arrays.asList( (Object[]) array ); //faster?
		int size = Array.getLength(array);
		ArrayList list = new ArrayList(size);
		for (int i=0; i<size; i++) {
			list.add( Array.get(array, i) );
		}
		return list;
	}

	public static String[] slice(String[] strings, int begin, int length) {
		String[] result = new String[length];
		System.arraycopy( strings, begin, result, 0, length );
		return result;
	}

	public static Object[] slice(Object[] objects, int begin, int length) {
		Object[] result = new Object[length];
		System.arraycopy( objects, begin, result, 0, length );
		return result;
	}

	public static List toList(Iterator iter) {
		List list = new ArrayList();
		while ( iter.hasNext() ) {
			list.add( iter.next() );
		}
		return list;
	}

	public static String[] join(String[] x, String[] y) {
		String[] result = new String[ x.length + y.length ];
		System.arraycopy( x, 0, result, 0, x.length );
		System.arraycopy( y, 0, result, x.length, y.length );
		return result;
	}

	public static String[] join(String[] x, String[] y, boolean[] use) {
		String[] result = new String[ x.length + countTrue(use) ];
		System.arraycopy( x, 0, result, 0, x.length );
		int k = x.length;
		for ( int i=0; i<y.length; i++ ) {
			if ( use[i] ) {
				result[k++] = y[i];
			}
		}
		return result;
	}

	public static int[] join(int[] x, int[] y) {
		int[] result = new int[ x.length + y.length ];
		System.arraycopy( x, 0, result, 0, x.length );
		System.arraycopy( y, 0, result, x.length, y.length );
		return result;
	}

	@SuppressWarnings( {"unchecked"})
	public static <T> T[] join(T[] x, T[] y) {
		T[] result = (T[]) Array.newInstance( x.getClass().getComponentType(), x.length + y.length );
		System.arraycopy( x, 0, result, 0, x.length );
		System.arraycopy( y, 0, result, x.length, y.length );
		return result;
	}

	public static final boolean[] TRUE = { true };
	public static final boolean[] FALSE = { false };

	private ArrayHelper() {}

	public static String toString( Object[] array ) {
		StringBuffer sb = new StringBuffer();
		sb.append("[");
		for (int i = 0; i < array.length; i++) {
			sb.append( array[i] );
			if( i<array.length-1 ) sb.append(",");
		}
		sb.append("]");
		return sb.toString();
	}

	public static boolean isAllNegative(int[] array) {
		for ( int i=0; i<array.length; i++ ) {
			if ( array[i] >=0 ) return false;
		}
		return true;
	}

	public static boolean isAllTrue(boolean[] array) {
		for ( int i=0; i<array.length; i++ ) {
			if ( !array[i] ) return false;
		}
		return true;
	}

	public static int countTrue(boolean[] array) {
		int result=0;
		for ( int i=0; i<array.length; i++ ) {
			if ( array[i] ) result++;
		}
		return result;
	}

	/*public static int countFalse(boolean[] array) {
		int result=0;
		for ( int i=0; i<array.length; i++ ) {
			if ( !array[i] ) result++;
		}
		return result;
	}*/

	public static boolean isAllFalse(boolean[] array) {
		for ( int i=0; i<array.length; i++ ) {
			if ( array[i] ) return false;
		}
		return true;
	}

	public static void addAll(Collection collection, Object[] array) {
		collection.addAll( Arrays.asList( array ) );
	}

	public static final String[] EMPTY_STRING_ARRAY = {};
	public static final int[] EMPTY_INT_ARRAY = {};
	public static final boolean[] EMPTY_BOOLEAN_ARRAY = {};
	public static final Class[] EMPTY_CLASS_ARRAY = {};
	public static final Object[] EMPTY_OBJECT_ARRAY = {};
	public static final Type[] EMPTY_TYPE_ARRAY = {};
	public static final byte[] EMPTY_BYTE_ARRAY = {};
	
	public static int[] getBatchSizes(int maxBatchSize) {
		int batchSize = maxBatchSize;
		int n=1;
		while ( batchSize>1 ) {
			batchSize = getNextBatchSize(batchSize);
			n++;
		}
		int[] result = new int[n];
		batchSize = maxBatchSize;
		for ( int i=0; i<n; i++ ) {
			result[i] = batchSize;
			batchSize = getNextBatchSize(batchSize);
		}
		return result;
	}
	
	private static int getNextBatchSize(int batchSize) {
		if (batchSize<=10) {
			return batchSize-1; //allow 9,8,7,6,5,4,3,2,1
		}
		else if (batchSize/2 < 10) {
			return 10;
		}
		else {
			return batchSize / 2;
		}
	}

	private static int SEED = 23;
	private static int PRIME_NUMER = 37;

	/**
	 * calculate the array hash (only the first level)
	 */
	public static int hash(Object[] array) {
		int length = array.length;
		int seed = SEED;
		for (int index = 0 ; index < length ; index++) {
			seed = hash( seed, array[index] == null ? 0 : array[index].hashCode() );
		}
		return seed;
	}

	/**
	 * calculate the array hash (only the first level)
	 */
	public static int hash(char[] array) {
		int length = array.length;
		int seed = SEED;
		for (int index = 0 ; index < length ; index++) {
			seed = hash( seed, array[index] ) ;
		}
		return seed;
	}

	/**
	 * calculate the array hash (only the first level)
	 */
	public static int hash(byte[] bytes) {
		int length = bytes.length;
		int seed = SEED;
		for (int index = 0 ; index < length ; index++) {
			seed = hash( seed, bytes[index] ) ;
		}
		return seed;
	}

	private static int hash(int seed, int i) {
		return PRIME_NUMER * seed + i;
	}

	/**
	 * Compare 2 arrays only at the first level
	 */
	public static boolean isEquals(Object[] o1, Object[] o2) {
		if (o1 == o2) return true;
		if (o1 == null || o2 == null) return false;
		int length = o1.length;
		if (length != o2.length) return false;
		for (int index = 0 ; index < length ; index++) {
			if ( ! o1[index].equals( o2[index] ) ) return false;
		}
        return true;
	}

	/**
	 * Compare 2 arrays only at the first level
	 */
	public static boolean isEquals(char[] o1, char[] o2) {
		if (o1 == o2) return true;
		if (o1 == null || o2 == null) return false;
		int length = o1.length;
		if (length != o2.length) return false;
		for (int index = 0 ; index < length ; index++) {
			if ( ! ( o1[index] == o2[index] ) ) return false;
		}
        return true;
	}

	/**
	 * Compare 2 arrays only at the first level
	 */
	public static boolean isEquals(byte[] b1, byte[] b2) {
		if (b1 == b2) return true;
		if (b1 == null || b2 == null) return false;
		int length = b1.length;
		if (length != b2.length) return false;
		for (int index = 0 ; index < length ; index++) {
			if ( ! ( b1[index] == b2[index] ) ) return false;
		}
        return true;
	}


}