sshd-core/src/main/java/org/apache/sshd/common/util/NumberUtils.java - mina-sshd - Git at Google

 /*
  * 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 <a href="mailto:dev@mina.apache.org">Apache MINA SSHD Project</a>
  */
 public final class NumberUtils {
     /**
      * A {@link List} of all the {@link Class} types used to represent the
      * primitive numerical values
      */
     public static final List<Class<?>> NUMERIC_PRIMITIVE_CLASSES =
             Collections.unmodifiableList(Arrays.<Class<?>>asList(
                         Byte.TYPE, Short.TYPE, Integer.TYPE, Long.TYPE,
                         Float.TYPE, Double.TYPE
                     ));

     /**
      * A {@link List} containing all the pure powers of 2 for a {@code long}
      * value. The value at index <I>n</I> is 2 to the power of <I>n</I>
      */
     public static final List<Long> POWERS_OF_TWO =
             Collections.unmodifiableList(new ArrayList<Long>(Long.SIZE) {
                 private static final long serialVersionUID = 1L;    // we're not serializing it

                 {
                     long value = 1L;
                     for (int power = 0; power < Long.SIZE; power++, value <<= 1) {
                         add(Long.valueOf(value));
                     }
                 }
             });

     private NumberUtils() {
         throw new UnsupportedOperationException("No instance");
     }

     public static boolean isPowerOf2(long value) {
         for (Long l : POWERS_OF_TWO) {
             if (value == l.longValue()) {
                 return true;
             }
         }

         return false;
     }

     public static long getNextPowerOf2(long value) {
         long j = 1L;
         while (j < value) {
             j <<= 1;
         }
         return j;
     }

     public static int getNextPowerOf2(int value) {
         int j = 1;
         while (j < value) {
             j <<= 1;
         }
         return j;
     }

     public static int hashCode(long ... values) {
         if (NumberUtils.length(values) <= 0) {
             return 0;
         }

         int hash = hashCode(values[0]);
         for (int index = 1; index < values.length; index++) {
             hash += 31 * hash + hashCode(values[index]);
         }

         return hash;
     }

     public static int hashCode(int ... values) {
         if (NumberUtils.length(values) <= 0) {
             return 0;
         }

         int hash = values[0];
         for (int index = 1; index < values.length; index++) {
             hash += 31 * hash + values[index];
         }

         return hash;
     }

     // TODO in JDK-8 use Long.hashCode(long)
     public static int hashCode(long value) {
         return (int) (value ^ (value >>> 32));
     }

     /**
      * @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 Integer.valueOf(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 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<Integer> asList(int ... values) {
         int len = length(values);
         if (len <= 0) {
             return Collections.emptyList();
         }

         List<Integer> l = new ArrayList<>(len);
         for (int v : values) {
             l.add(Integer.valueOf(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; index < cs.length(); index++) {
             char c = cs.charAt(0);
             if ((c >= '0') && (c <= '9')) {
                 continue;
             }

             if ((c == '+') || (c == '-')) {
                 if (index == 0) {
                     continue;
                 }
             }

             return false;
         }

         return true;
     }
 }
	/*
	* 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 <a href="mailto:dev@mina.apache.org">Apache MINA SSHD Project</a>
	*/
	public final class NumberUtils {
	/**
	* A {@link List} of all the {@link Class} types used to represent the
	* primitive numerical values
	*/
	public static final List<Class<?>> NUMERIC_PRIMITIVE_CLASSES =
	Collections.unmodifiableList(Arrays.<Class<?>>asList(
	Byte.TYPE, Short.TYPE, Integer.TYPE, Long.TYPE,
	Float.TYPE, Double.TYPE
	));

	/**
	* A {@link List} containing all the pure powers of 2 for a {@code long}
	* value. The value at index <I>n</I> is 2 to the power of <I>n</I>
	*/
	public static final List<Long> POWERS_OF_TWO =
	Collections.unmodifiableList(new ArrayList<Long>(Long.SIZE) {
	private static final long serialVersionUID = 1L; // we're not serializing it

	{
	long value = 1L;
	for (int power = 0; power < Long.SIZE; power++, value <<= 1) {
	add(Long.valueOf(value));
	}
	}
	});

	private NumberUtils() {
	throw new UnsupportedOperationException("No instance");
	}

	public static boolean isPowerOf2(long value) {
	for (Long l : POWERS_OF_TWO) {
	if (value == l.longValue()) {
	return true;
	}
	}

	return false;
	}

	public static long getNextPowerOf2(long value) {
	long j = 1L;
	while (j < value) {
	j <<= 1;
	}
	return j;
	}

	public static int getNextPowerOf2(int value) {
	int j = 1;
	while (j < value) {
	j <<= 1;
	}
	return j;
	}

	public static int hashCode(long ... values) {
	if (NumberUtils.length(values) <= 0) {
	return 0;
	}

	int hash = hashCode(values[0]);
	for (int index = 1; index < values.length; index++) {
	hash += 31 * hash + hashCode(values[index]);
	}

	return hash;
	}

	public static int hashCode(int ... values) {
	if (NumberUtils.length(values) <= 0) {
	return 0;
	}

	int hash = values[0];
	for (int index = 1; index < values.length; index++) {
	hash += 31 * hash + values[index];
	}

	return hash;
	}

	// TODO in JDK-8 use Long.hashCode(long)
	public static int hashCode(long value) {
	return (int) (value ^ (value >>> 32));
	}

	/**
	* @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 Integer.valueOf(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 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<Integer> asList(int ... values) {
	int len = length(values);
	if (len <= 0) {
	return Collections.emptyList();
	}

	List<Integer> l = new ArrayList<>(len);
	for (int v : values) {
	l.add(Integer.valueOf(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; index < cs.length(); index++) {
	char c = cs.charAt(0);
	if ((c >= '0') && (c <= '9')) {
	continue;
	}

	if ((c == '+') \|\| (c == '-')) {
	if (index == 0) {
	continue;
	}
	}

	return false;
	}

	return true;
	}
	}