org.apache.sshd.common.util.NumberUtils Maven / Gradle / Ivy
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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including
all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and
JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up
with different versions on classes on the class path).
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.sshd.common.util;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
/**
* @author Apache MINA SSHD Project
*/
public final class NumberUtils {
/**
* A {@link List} of all the {@link Class} types used to represent the primitive numerical values
*/
public static final List> NUMERIC_PRIMITIVE_CLASSES = GenericUtils.unmodifiableList(
Byte.TYPE, Short.TYPE, Integer.TYPE, Long.TYPE, Float.TYPE, Double.TYPE);
private NumberUtils() {
throw new UnsupportedOperationException("No instance");
}
/**
* @param value The original (non-negative) value
* @return The closest positive power of 2 that is greater or equal to the value. If none can be found
* then returns the original value
*/
public static int getNextPowerOf2(int value) {
if (value < 0) {
throw new IllegalArgumentException("Negative value N/A: " + value);
}
int j = 1;
while (j < value) {
j <<= 1;
// Did we stumble onto the realm of values beyond 2GB ?
if (j <= 0) {
return value;
}
}
return j;
}
public static int hashCode(long... values) {
return Arrays.hashCode(values);
}
public static int hashCode(int... values) {
return Arrays.hashCode(values);
}
public static int hashCode(byte... values) {
return Arrays.hashCode(values);
}
public static int hashCode(byte[] a, int offset, int len) {
if (len == 0) {
return 0;
}
int result = 1;
for (int pos = offset, count = 0; count < len; pos++, count++) {
byte element = a[pos];
result = 31 * result + element;
}
return result;
}
public static int diffOffset(byte[] a1, int startPos1, byte[] a2, int startPos2, int len) {
for (int pos1 = startPos1, pos2 = startPos2, count = 0; count < len; pos1++, pos2++, count++) {
byte v1 = a1[pos1];
byte v2 = a2[pos2];
if (v1 != v2) {
return count;
}
}
return -1;
}
/**
* @param clazz The {@link Class} to examine - ignored if {@code null}
* @return If the class is a {@link Number} or one of the primitive numerical types
* @see #NUMERIC_PRIMITIVE_CLASSES
*/
public static boolean isNumericClass(Class clazz) {
if (clazz == null) {
return false;
}
// turns out that the primitive types are not assignable to Number
if (Number.class.isAssignableFrom(clazz)) {
return true;
}
return NUMERIC_PRIMITIVE_CLASSES.indexOf(clazz) >= 0;
}
/**
* Converts a {@link Number} into an {@link Integer} if not already such
*
* @param n The {@link Number} - ignored if {@code null}
* @return The equivalent {@link Integer} value
*/
public static Integer toInteger(Number n) {
if (n == null) {
return null;
} else if (n instanceof Integer) {
return (Integer) n;
} else {
return n.intValue();
}
}
public static String join(CharSequence separator, long... values) {
if (NumberUtils.isEmpty(values)) {
return "";
}
StringBuilder sb = new StringBuilder(values.length * Byte.SIZE);
for (long v : values) {
if (sb.length() > 0) {
sb.append(separator);
}
sb.append(v);
}
return sb.toString();
}
public static String join(char separator, long... values) {
if (NumberUtils.isEmpty(values)) {
return "";
}
StringBuilder sb = new StringBuilder(values.length * Byte.SIZE);
for (long v : values) {
if (sb.length() > 0) {
sb.append(separator);
}
sb.append(v);
}
return sb.toString();
}
public static String join(CharSequence separator, boolean unsigned, byte... values) {
if (NumberUtils.isEmpty(values)) {
return "";
}
StringBuilder sb = new StringBuilder(values.length * Byte.SIZE);
for (byte v : values) {
if (sb.length() > 0) {
sb.append(separator);
}
sb.append(unsigned ? (v & 0xFF) : v);
}
return sb.toString();
}
public static String join(char separator, boolean unsigned, byte... values) {
if (NumberUtils.isEmpty(values)) {
return "";
}
StringBuilder sb = new StringBuilder(values.length * Byte.SIZE);
for (byte v : values) {
if (sb.length() > 0) {
sb.append(separator);
}
sb.append(unsigned ? (v & 0xFF) : v);
}
return sb.toString();
}
public static String join(CharSequence separator, int... values) {
if (NumberUtils.isEmpty(values)) {
return "";
}
StringBuilder sb = new StringBuilder(values.length * Byte.SIZE);
for (int v : values) {
if (sb.length() > 0) {
sb.append(separator);
}
sb.append(v);
}
return sb.toString();
}
public static String join(char separator, int... values) {
if (NumberUtils.isEmpty(values)) {
return "";
}
StringBuilder sb = new StringBuilder(values.length * Byte.SIZE);
for (int v : values) {
if (sb.length() > 0) {
sb.append(separator);
}
sb.append(v);
}
return sb.toString();
}
public static byte[] emptyIfNull(byte[] a) {
return (a == null) ? GenericUtils.EMPTY_BYTE_ARRAY : a;
}
public static boolean isEmpty(byte[] a) {
return NumberUtils.length(a) <= 0;
}
public static boolean isEmpty(int[] a) {
return NumberUtils.length(a) <= 0;
}
public static boolean isEmpty(long[] a) {
return NumberUtils.length(a) <= 0;
}
public static int length(byte... a) {
return (a == null) ? 0 : a.length;
}
public static int length(int... a) {
return (a == null) ? 0 : a.length;
}
public static int length(long... a) {
return (a == null) ? 0 : a.length;
}
public static List asList(int... values) {
int len = length(values);
if (len <= 0) {
return Collections.emptyList();
}
List l = new ArrayList<>(len);
for (int v : values) {
l.add(v);
}
return l;
}
/**
* Checks if optional sign and all others are '0'-'9'
*
* @param cs The {@link CharSequence} to check
* @return {@code true} if valid integer number
*/
public static boolean isIntegerNumber(CharSequence cs) {
if (GenericUtils.isEmpty(cs)) {
return false;
}
for (int index = 0, len = cs.length(); index < len; index++) {
char c = cs.charAt(index);
if ((c >= '0') && (c <= '9')) {
continue;
}
if ((c == '+') || (c == '-')) {
if (index == 0) {
continue;
}
}
return false;
}
return true;
}
}