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ratel api,used for developer on ratel system,an extension for xposed framewrok,ratel api compatable with original xposed framework

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/*
 * 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 external.org.apache.commons.lang3;

import java.io.Serializable;
import java.lang.reflect.Array;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.Map;
import java.util.TreeSet;


import external.org.apache.commons.lang3.exception.CloneFailedException;
import external.org.apache.commons.lang3.mutable.MutableInt;

/**
 * 

Operations on {@code Object}.

* *

This class tries to handle {@code null} input gracefully. * An exception will generally not be thrown for a {@code null} input. * Each method documents its behaviour in more detail.

* *

#ThreadSafe#

* @since 1.0 * @version $Id: ObjectUtils.java 1199894 2011-11-09 17:53:59Z ggregory $ */ //@Immutable public class ObjectUtils { /** *

Singleton used as a {@code null} placeholder where * {@code null} has another meaning.

* *

For example, in a {@code HashMap} the * {@link java.util.HashMap#get(java.lang.Object)} method returns * {@code null} if the {@code Map} contains {@code null} or if there * is no matching key. The {@code Null} placeholder can be used to * distinguish between these two cases.

* *

Another example is {@code Hashtable}, where {@code null} * cannot be stored.

* *

This instance is Serializable.

*/ public static final Null NULL = new Null(); /** *

{@code ObjectUtils} instances should NOT be constructed in * standard programming. Instead, the static methods on the class should * be used, such as {@code ObjectUtils.defaultIfNull("a","b");}.

* *

This constructor is public to permit tools that require a JavaBean * instance to operate.

*/ public ObjectUtils() { super(); } // Defaulting //----------------------------------------------------------------------- /** *

Returns a default value if the object passed is {@code null}.

* *
     * ObjectUtils.defaultIfNull(null, null)      = null
     * ObjectUtils.defaultIfNull(null, "")        = ""
     * ObjectUtils.defaultIfNull(null, "zz")      = "zz"
     * ObjectUtils.defaultIfNull("abc", *)        = "abc"
     * ObjectUtils.defaultIfNull(Boolean.TRUE, *) = Boolean.TRUE
     * 
* * @param the type of the object * @param object the {@code Object} to test, may be {@code null} * @param defaultValue the default value to return, may be {@code null} * @return {@code object} if it is not {@code null}, defaultValue otherwise */ public static T defaultIfNull(T object, T defaultValue) { return object != null ? object : defaultValue; } /** *

Returns the first value in the array which is not {@code null}. * If all the values are {@code null} or the array is {@code null} * or empty then {@code null} is returned.

* *
     * ObjectUtils.firstNonNull(null, null)      = null
     * ObjectUtils.firstNonNull(null, "")        = ""
     * ObjectUtils.firstNonNull(null, null, "")  = ""
     * ObjectUtils.firstNonNull(null, "zz")      = "zz"
     * ObjectUtils.firstNonNull("abc", *)        = "abc"
     * ObjectUtils.firstNonNull(null, "xyz", *)  = "xyz"
     * ObjectUtils.firstNonNull(Boolean.TRUE, *) = Boolean.TRUE
     * ObjectUtils.firstNonNull()                = null
     * 
* * @param the component type of the array * @param values the values to test, may be {@code null} or empty * @return the first value from {@code values} which is not {@code null}, * or {@code null} if there are no non-null values * @since 3.0 */ public static T firstNonNull(T... values) { if (values != null) { for (T val : values) { if (val != null) { return val; } } } return null; } // Null-safe equals/hashCode //----------------------------------------------------------------------- /** *

Compares two objects for equality, where either one or both * objects may be {@code null}.

* *
     * ObjectUtils.equals(null, null)                  = true
     * ObjectUtils.equals(null, "")                    = false
     * ObjectUtils.equals("", null)                    = false
     * ObjectUtils.equals("", "")                      = true
     * ObjectUtils.equals(Boolean.TRUE, null)          = false
     * ObjectUtils.equals(Boolean.TRUE, "true")        = false
     * ObjectUtils.equals(Boolean.TRUE, Boolean.TRUE)  = true
     * ObjectUtils.equals(Boolean.TRUE, Boolean.FALSE) = false
     * 
* * @param object1 the first object, may be {@code null} * @param object2 the second object, may be {@code null} * @return {@code true} if the values of both objects are the same */ public static boolean equals(Object object1, Object object2) { if (object1 == object2) { return true; } if (object1 == null || object2 == null) { return false; } return object1.equals(object2); } /** *

Compares two objects for inequality, where either one or both * objects may be {@code null}.

* *
     * ObjectUtils.notEqual(null, null)                  = false
     * ObjectUtils.notEqual(null, "")                    = true
     * ObjectUtils.notEqual("", null)                    = true
     * ObjectUtils.notEqual("", "")                      = false
     * ObjectUtils.notEqual(Boolean.TRUE, null)          = true
     * ObjectUtils.notEqual(Boolean.TRUE, "true")        = true
     * ObjectUtils.notEqual(Boolean.TRUE, Boolean.TRUE)  = false
     * ObjectUtils.notEqual(Boolean.TRUE, Boolean.FALSE) = true
     * 
* * @param object1 the first object, may be {@code null} * @param object2 the second object, may be {@code null} * @return {@code false} if the values of both objects are the same */ public static boolean notEqual(Object object1, Object object2) { return ObjectUtils.equals(object1, object2) == false; } /** *

Gets the hash code of an object returning zero when the * object is {@code null}.

* *
     * ObjectUtils.hashCode(null)   = 0
     * ObjectUtils.hashCode(obj)    = obj.hashCode()
     * 
* * @param obj the object to obtain the hash code of, may be {@code null} * @return the hash code of the object, or zero if null * @since 2.1 */ public static int hashCode(Object obj) { // hashCode(Object) retained for performance, as hash code is often critical return obj == null ? 0 : obj.hashCode(); } /** *

Gets the hash code for multiple objects.

* *

This allows a hash code to be rapidly calculated for a number of objects. * The hash code for a single object is the not same as {@link #hashCode(Object)}. * The hash code for multiple objects is the same as that calculated by an * {@code ArrayList} containing the specified objects.

* *
     * ObjectUtils.hashCodeMulti()                 = 1
     * ObjectUtils.hashCodeMulti((Object[]) null)  = 1
     * ObjectUtils.hashCodeMulti(a)                = 31 + a.hashCode()
     * ObjectUtils.hashCodeMulti(a,b)              = (31 + a.hashCode()) * 31 + b.hashCode()
     * ObjectUtils.hashCodeMulti(a,b,c)            = ((31 + a.hashCode()) * 31 + b.hashCode()) * 31 + c.hashCode()
     * 
* * @param objects the objects to obtain the hash code of, may be {@code null} * @return the hash code of the objects, or zero if null * @since 3.0 */ public static int hashCodeMulti(Object... objects) { int hash = 1; if (objects != null) { for (Object object : objects) { hash = hash * 31 + ObjectUtils.hashCode(object); } } return hash; } // Identity ToString //----------------------------------------------------------------------- /** *

Gets the toString that would be produced by {@code Object} * if a class did not override toString itself. {@code null} * will return {@code null}.

* *
     * ObjectUtils.identityToString(null)         = null
     * ObjectUtils.identityToString("")           = "java.lang.String@1e23"
     * ObjectUtils.identityToString(Boolean.TRUE) = "java.lang.Boolean@7fa"
     * 
* * @param object the object to create a toString for, may be * {@code null} * @return the default toString text, or {@code null} if * {@code null} passed in */ public static String identityToString(Object object) { if (object == null) { return null; } StringBuffer buffer = new StringBuffer(); identityToString(buffer, object); return buffer.toString(); } /** *

Appends the toString that would be produced by {@code Object} * if a class did not override toString itself. {@code null} * will throw a NullPointerException for either of the two parameters.

* *
     * ObjectUtils.identityToString(buf, "")            = buf.append("java.lang.String@1e23"
     * ObjectUtils.identityToString(buf, Boolean.TRUE)  = buf.append("java.lang.Boolean@7fa"
     * ObjectUtils.identityToString(buf, Boolean.TRUE)  = buf.append("java.lang.Boolean@7fa")
     * 
* * @param buffer the buffer to append to * @param object the object to create a toString for * @since 2.4 */ public static void identityToString(StringBuffer buffer, Object object) { if (object == null) { throw new NullPointerException("Cannot get the toString of a null identity"); } buffer.append(object.getClass().getName()) .append('@') .append(Integer.toHexString(System.identityHashCode(object))); } // ToString //----------------------------------------------------------------------- /** *

Gets the {@code toString} of an {@code Object} returning * an empty string ("") if {@code null} input.

* *
     * ObjectUtils.toString(null)         = ""
     * ObjectUtils.toString("")           = ""
     * ObjectUtils.toString("bat")        = "bat"
     * ObjectUtils.toString(Boolean.TRUE) = "true"
     * 
* * @see StringUtils#defaultString(String) * @see String#valueOf(Object) * @param obj the Object to {@code toString}, may be null * @return the passed in Object's toString, or nullStr if {@code null} input * @since 2.0 */ public static String toString(Object obj) { return obj == null ? "" : obj.toString(); } /** *

Gets the {@code toString} of an {@code Object} returning * a specified text if {@code null} input.

* *
     * ObjectUtils.toString(null, null)           = null
     * ObjectUtils.toString(null, "null")         = "null"
     * ObjectUtils.toString("", "null")           = ""
     * ObjectUtils.toString("bat", "null")        = "bat"
     * ObjectUtils.toString(Boolean.TRUE, "null") = "true"
     * 
* * @see StringUtils#defaultString(String,String) * @see String#valueOf(Object) * @param obj the Object to {@code toString}, may be null * @param nullStr the String to return if {@code null} input, may be null * @return the passed in Object's toString, or nullStr if {@code null} input * @since 2.0 */ public static String toString(Object obj, String nullStr) { return obj == null ? nullStr : obj.toString(); } // Comparable //----------------------------------------------------------------------- /** *

Null safe comparison of Comparables.

* * @param type of the values processed by this method * @param values the set of comparable values, may be null * @return *
    *
  • If any objects are non-null and unequal, the lesser object. *
  • If all objects are non-null and equal, the first. *
  • If any of the comparables are null, the lesser of the non-null objects. *
  • If all the comparables are null, null is returned. *
*/ public static > T min(T... values) { T result = null; if (values != null) { for (T value : values) { if (compare(value, result, true) < 0) { result = value; } } } return result; } /** *

Null safe comparison of Comparables.

* * @param type of the values processed by this method * @param values the set of comparable values, may be null * @return *
    *
  • If any objects are non-null and unequal, the greater object. *
  • If all objects are non-null and equal, the first. *
  • If any of the comparables are null, the greater of the non-null objects. *
  • If all the comparables are null, null is returned. *
*/ public static > T max(T... values) { T result = null; if (values != null) { for (T value : values) { if (compare(value, result, false) > 0) { result = value; } } } return result; } /** *

Null safe comparison of Comparables. * {@code null} is assumed to be less than a non-{@code null} value.

* * @param type of the values processed by this method * @param c1 the first comparable, may be null * @param c2 the second comparable, may be null * @return a negative value if c1 < c2, zero if c1 = c2 * and a positive value if c1 > c2 */ public static > int compare(T c1, T c2) { return compare(c1, c2, false); } /** *

Null safe comparison of Comparables.

* * @param type of the values processed by this method * @param c1 the first comparable, may be null * @param c2 the second comparable, may be null * @param nullGreater if true {@code null} is considered greater * than a non-{@code null} value or if false {@code null} is * considered less than a Non-{@code null} value * @return a negative value if c1 < c2, zero if c1 = c2 * and a positive value if c1 > c2 * @see java.util.Comparator#compare(Object, Object) */ public static > int compare(T c1, T c2, boolean nullGreater) { if (c1 == c2) { return 0; } else if (c1 == null) { return nullGreater ? 1 : -1; } else if (c2 == null) { return nullGreater ? -1 : 1; } return c1.compareTo(c2); } /** * Find the "best guess" middle value among comparables. If there is an even * number of total values, the lower of the two middle values will be returned. * @param type of values processed by this method * @param items to compare * @return T at middle position * @throws NullPointerException if items is {@code null} * @throws IllegalArgumentException if items is empty or contains {@code null} values * @since 3.0.1 */ public static > T median(T... items) { Validate.notEmpty(items); Validate.noNullElements(items); TreeSet sort = new TreeSet(); Collections.addAll(sort, items); @SuppressWarnings("unchecked") //we know all items added were T instances T result = (T) sort.toArray()[(sort.size() - 1) / 2]; return result; } /** * Find the "best guess" middle value among comparables. If there is an even * number of total values, the lower of the two middle values will be returned. * @param type of values processed by this method * @param comparator to use for comparisons * @param items to compare * @return T at middle position * @throws NullPointerException if items or comparator is {@code null} * @throws IllegalArgumentException if items is empty or contains {@code null} values * @since 3.0.1 */ public static T median(Comparator comparator, T... items) { Validate.notEmpty(items, "null/empty items"); Validate.noNullElements(items); Validate.notNull(comparator, "null comparator"); TreeSet sort = new TreeSet(comparator); Collections.addAll(sort, items); @SuppressWarnings("unchecked") //we know all items added were T instances T result = (T) sort.toArray()[(sort.size() - 1) / 2]; return result; } // Mode //----------------------------------------------------------------------- /** * Find the most frequently occurring item. * * @param type of values processed by this method * @param items to check * @return most populous T, {@code null} if non-unique or no items supplied * @since 3.0.1 */ public static T mode(T... items) { if (ArrayUtils.isNotEmpty(items)) { HashMap occurrences = new HashMap(items.length); for (T t : items) { MutableInt count = occurrences.get(t); if (count == null) { occurrences.put(t, new MutableInt(1)); } else { count.increment(); } } T result = null; int max = 0; for (Map.Entry e : occurrences.entrySet()) { int cmp = e.getValue().intValue(); if (cmp == max) { result = null; } else if (cmp > max) { max = cmp; result = e.getKey(); } } return result; } return null; } // cloning //----------------------------------------------------------------------- /** *

Clone an object.

* * @param the type of the object * @param obj the object to clone, null returns null * @return the clone if the object implements {@link Cloneable} otherwise {@code null} * @throws CloneFailedException if the object is cloneable and the clone operation fails * @since 3.0 */ public static T clone(final T obj) { if (obj instanceof Cloneable) { final Object result; if (obj.getClass().isArray()) { final Class componentType = obj.getClass().getComponentType(); if (!componentType.isPrimitive()) { result = ((Object[]) obj).clone(); } else { int length = Array.getLength(obj); result = Array.newInstance(componentType, length); while (length-- > 0) { Array.set(result, length, Array.get(obj, length)); } } } else { try { final Method clone = obj.getClass().getMethod("clone"); result = clone.invoke(obj); } catch (final NoSuchMethodException e) { throw new CloneFailedException("Cloneable type " + obj.getClass().getName() + " has no clone method", e); } catch (final IllegalAccessException e) { throw new CloneFailedException("Cannot clone Cloneable type " + obj.getClass().getName(), e); } catch (final InvocationTargetException e) { throw new CloneFailedException("Exception cloning Cloneable type " + obj.getClass().getName(), e.getCause()); } } @SuppressWarnings("unchecked") final T checked = (T) result; return checked; } return null; } /** *

Clone an object if possible.

* *

This method is similar to {@link #clone(Object)}, but will return the provided * instance as the return value instead of {@code null} if the instance * is not cloneable. This is more convenient if the caller uses different * implementations (e.g. of a service) and some of the implementations do not allow concurrent * processing or have state. In such cases the implementation can simply provide a proper * clone implementation and the caller's code does not have to change.

* * @param the type of the object * @param obj the object to clone, null returns null * @return the clone if the object implements {@link Cloneable} otherwise the object itself * @throws CloneFailedException if the object is cloneable and the clone operation fails * @since 3.0 */ public static T cloneIfPossible(final T obj) { final T clone = clone(obj); return clone == null ? obj : clone; } // Null //----------------------------------------------------------------------- /** *

Class used as a null placeholder where {@code null} * has another meaning.

* *

For example, in a {@code HashMap} the * {@link java.util.HashMap#get(java.lang.Object)} method returns * {@code null} if the {@code Map} contains {@code null} or if there is * no matching key. The {@code Null} placeholder can be used to distinguish * between these two cases.

* *

Another example is {@code Hashtable}, where {@code null} * cannot be stored.

*/ public static class Null implements Serializable { /** * Required for serialization support. Declare serialization compatibility with Commons Lang 1.0 * * @see java.io.Serializable */ private static final long serialVersionUID = 7092611880189329093L; /** * Restricted constructor - singleton. */ Null() { super(); } /** *

Ensure singleton.

* * @return the singleton value */ private Object readResolve() { return ObjectUtils.NULL; } } }




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