很久没有上博客园了 ， 最近一段时间，因为工作的关系时间上比较闲，利用闲暇时间重新翻了一下丢弃很久的C++语言 。C++从98、11、14、17目前已经也走到了20版本，发生了很多变化，也引入了很多新的语言特性和库，让开发也更加的便、高效 。
但用惯了Java后，发现其中Java的容器流式操作特别简单，封装的很是优雅 。而在C++中，针对容器的操作，与算法是完全分隔的 ， 操作起来利用迭代器进行串接，这种方式其实本身实际上复用效率特别高效，但是对于开发者来说，又显得有些低效，考虑到这个问题，我自己对C++的容器与算法，简单做了一个封装 。
话不多说，直接上代码，让大家看看效果！
示例代码
vector<int> vec = {1, 3, 4, 6, 4, 2, 11, 9};auto minmax = JavaStyleStream<vector, int>(vec).filter([](int i) { return i % 3 == 0; }).transform([](int i){return i*2.5;}).sort().for_each([](double i) { std::cout << i << " ";}).minmax();cout << minmax.first << ":" << minmax.second << endl;最终结果
【Java Style的C++容器流式处理类】7.5 15 22.5 7.5:22.5看到这里，是不是觉得容器操作起来要高效很多 ， 不用再面对一成不变的迭代器了 。
详细的Java Style容器流式封装类 ， 见下面代码（未完整封装C++所有算法，工作还在进行中）,觉得好用，麻烦点个赞，也欢迎大家提出宝贵意见
//// Created by AILI on 2022/10/6.//#ifndef CPPTEST_JAVASTYLESTREAM_H#define CPPTEST_JAVASTYLESTREAM_H#include <algorithm>#include "function_traits.h"//template <template<typename, typename> class Cont>//struct Stream {};template<template<typename T1, typename T2> class Cont, typename Tp, typename Alloc = std::allocator<Tp>>class JavaStyleStream {public:typedef typename Cont<Tp, Alloc>::value_type value_type;typedef typename Cont<Tp, Alloc>::pointerpointer;typedef typename Cont<Tp, Alloc>::const_pointer const_pointer;typedef typename Cont<Tp, Alloc>::referencereference;typedef typename Cont<Tp, Alloc>::const_reference const_reference;typedef typename Cont<Tp, Alloc>::iteratoriterator;typedef typename Cont<Tp, Alloc>::const_iterator const_iterator;typedef typename Cont<Tp, Alloc>::const_reverse_iterator const_reverse_iterator;typedef typename Cont<Tp, Alloc>::reverse_iterator reverse_iterator;typedef typename Cont<Tp, Alloc>::size_type size_type;typedef typename Cont<Tp, Alloc>::difference_typedifference_type;typedef typename Cont<Tp, Alloc>::allocator_type allocator_type;//聚合value_type max() {return *max_element();}template<typename _Compare>value_type max(_Compare compare) {return *max_element();}iterator max_element() {return std::max_element(_container.begin(), _container.end());}template<typename _Compare>iterator max_element(_Compare compare) {return std::max_element(_container.begin(), _container.end(), compare);}value_type min() {return *min_element();}template<typename _Compare>value_type min(_Compare compare) {return *min_element(compare);}iterator min_element() {return std::min(_container.begin(), _container.end());}template<typename _Compare>iterator min_element(_Compare compare) {return std::min(_container.begin(), _container.end(), compare);}pair<value_type, value_type> minmax() {pair<const_iterator, const_iterator> r = minmax_element();return pair<value_type, value_type>(*(r.first), *(r.second));}pair<const_iterator, const_iterator> minmax_element() {return std::minmax_element(_container.begin(), _container.end());}template<typename _Compare>pair<const_iterator, const_iterator> minmax_element(_Compare compare) {return std::minmax_element(_container.begin(), _container.end(), compare);}difference_type count(const value_type& value) {return std::count(_container.begin(), _container.end(), value);}template<typename _Predicate>difference_type count_if(_Predicate predicate) {return std::count_if(_container.begin(), _container.end(), predicate);}//查找template<typename _Predicate>bool all_of(_Predicate predicate) {return std::all_of(_container.begin(), _container.end(), predicate);}template<typename _Predicate>bool any_of(_Predicate predicate) {return std::any_of(_container.begin(), _container.end(), predicate);}template<typename _Predicate>bool none_of(_Predicate predicate) {return std::none_of(_container.begin(), _container.end(), predicate);}iterator adjacent_find() {return std::adjacent_find(_container.begin(), _container.end());}template<typename _BinaryPredicate>iterator adjacent_find(_BinaryPredicate predicate) {return std::adjacent_find(_container.begin(), _container.end(), predicate);}iterator find(const value_type& value) {return std::find(_container.begin(), _container.end(), value);}template<typename _Predicate>iterator find_if(_Predicate predicate) {return std::find_if(_container.begin(), _container.end(), predicate);}iterator find_first_of(iterator find_begin, iterator find_end) {return std::find_first_of(_container.begin(), _container.end(), find_begin, find_end);}template<typename _BinaryPredicate>iterator find_first_of(iterator find_begin, iterator find_end, _BinaryPredicate predicate) {return std::find_first_of(_container.begin(), _container.end(), find_begin, find_end, predicate);}iterator find_end(iterator find_begin, iterator find_end) {return std::find_end(_container.begin(), _container.end(), find_begin, find_end);}template<typename _BinaryPredicate>iterator find_end(iterator find_begin, iterator find_end, _BinaryPredicate predicate) {return std::find_end(_container.begin(), _container.end(), find_begin, find_end, predicate);}iterator binary_search(const value_type& value) {return std::binary_search(_container.begin(), _container.end(), value);}template<typename _Compare>iterator binary_search(const value_type& value, _Compare compare) {return std::binary_search(_container.begin(), _container.end(), value, compare);}iterator search(const value_type& value) {return std::search(_container.begin(), _container.end(), value);}template<typename _BinaryPredicate>iterator search(iterator find_begin, iterator find_end, _BinaryPredicate predicate) {return std::search(_container.begin(), _container.end(), find_begin, find_end, predicate);}iterator search_n(size_type n, const value_type& value) {return std::search_n(_container.begin(), _container.end(), n, value);}template<typename _BinaryPredicate>iterator search_n(size_type n, const value_type& value, _BinaryPredicate predicate) {return std::search_n(_container.begin(), _container.end(), n, value, predicate);}iterator lower_bound(const value_type& value) {return std::lower_bound(_container.begin(), _container.end(), value);}template<typename _Compare>iterator lower_bound(const value_type& value, _Compare compare) {return std::lower_bound(_container.begin(), _container.end(), value, compare);}iterator upper_bound(const value_type& value) {return std::upper_bound(_container.begin(), _container.end(), value);}template<typename _Compare>iterator upper_bound(const value_type& value, _Compare compare) {return std::upper_bound(_container.begin(), _container.end(), value, compare);}//排序bool is_sorted() {return std::is_sorted(_container.begin(), _container.end());}template<typename _Compare>bool is_sorted(_Compare compare) {return std::is_sorted(_container.begin(), _container.end(), compare);}bool is_sorted_until() {return std::is_sorted_until(_container.begin(), _container.end());}template<typename _Compare>bool is_sorted_until(_Compare compare) {return std::is_sorted_until(_container.begin(), _container.end(), compare);}JavaStyleStream& sort() {std::sort(_container.begin(), _container.end());return *this;}template<typename _Compare>JavaStyleStream& sort(_Compare compare) {std::sort(_container.begin(), _container.end(), compare);return *this;}template<typename _Integer>JavaStyleStream& partial_sort(_Integer integer) {std::partial_sort(_container.begin(), _container.begin() + integer, _container.end());return *this;}template<typename _Integer, typename _Compare>JavaStyleStream& partial_sort(_Integer integer, _Compare compare) {std::partial_sort(_container.begin(), _container.begin() + integer, _container.end(), compare);return *this;}JavaStyleStream& stable_sort() {std::stable_sort(_container.begin(), _container.end());return *this;}template<typename _Compare>JavaStyleStream& stable_sort(_Compare compare) {std::stable_sort(_container.begin(), _container.end(), compare);return *this;}template<typename _Integer>JavaStyleStream& nth_element(_Integer integer) {std::nth_element(_container.begin(), _container.begin() + integer, _container.end());return *this;}template<typename _Integer, typename _Compare>JavaStyleStream& nth_element(_Integer integer, _Compare compare) {std::nth_element(_container.begin(), _container.begin() + integer, _container.end(), compare);return *this;}JavaStyleStream& shuffle() {std::shuffle(_container.begin(), _container.end());return *this;}template<typename _Generator>JavaStyleStream& shuffle(_Generator generator) {std::shuffle(_container.begin(), _container.end(), generator);return *this;}JavaStyleStream& random_shuffle() {std::random_shuffle(_container.begin(), _container.end());return *this;}template<typename _Generator>JavaStyleStream& random_shuffle(_Generator generator) {std::random_shuffle(_container.begin(), _container.end(), generator);return *this;}//删除&替换JavaStyleStream& remove_erase(const value_type& value) {_container.erase(std::remove(_container.begin(), _container.end(), value), _container.end());return *this;}template<typename _Predicate>JavaStyleStream& remove_erase(_Predicate predicate) {_container.erase(std::remove_if(_container.begin(), _container.end(), predicate), _container.end());return *this;}JavaStyleStream& repalce(const value_type& old_value, const value_type& new_value) {std::replace(_container.begin(), _container.end(), old_value, new_value);return *this;}template<typename _Predicate>JavaStyleStream& replace_if(_Predicate predicate, const value_type& new_value) {std::remove_if(_container.begin(), _container.end(), predicate, new_value);return *this;}//反转&旋转JavaStyleStream& reverse() {std::reverse(_container.begin(), _container.end());return *this;}template<typename _Integer>JavaStyleStream& reverse(_Integer integer) {std::rotate(_container.begin(), _container.begin() + integer, _container.end());return *this;}//归一化JavaStyleStream& unique() {std::unique(_container.begin(), _container.end());return *this;}template<typename _BinaryPredicate>JavaStyleStream& unique(_BinaryPredicate predicate) {std::unique(_container.begin(), _container.end(), predicate);return *this;}//分组(是否需要返回分组迭代器？）template<typename _Predicate>JavaStyleStream& partition(_Predicate predicate) {std::partition(_container.begin(), _container.end(), predicate);return *this;}template<typename _Predicate>JavaStyleStream& stable_partition(_Predicate predicate) {std::stable_partition(_container.begin(), _container.end(), predicate);return *this;}//C++11提供template<typename _Predicate>JavaStyleStream& partition_point(_Predicate predicate) {std::partition_point(_container.begin(), _container.end(), predicate);return *this;}//过滤&复制&合并&转换template<typename _Predicate>JavaStyleStream filter(_Predicate predicate) {Cont<Tp, Alloc> newCont;for(iterator iter = _container.begin(); iter != _container.end(); ++iter) {if (predicate(*iter)) {newCont.push_back(*iter);}}JavaStyleStream<Cont, Tp> newSteram(newCont);return std::move(newSteram);}template<typename _UnaryFunction>JavaStyleStream<Cont, typename function_traits<_UnaryFunction>::return_type> transform(_UnaryFunction function) {Cont<typename function_traits<_UnaryFunction>::return_type, std::allocator<typename function_traits<_UnaryFunction>::return_type>> newCont;std::transform(_container.begin(), _container.end(), std::back_inserter(newCont), function);JavaStyleStream<Cont, typename function_traits<_UnaryFunction>::return_type, std::allocator<typename function_traits<_UnaryFunction>::return_type>> newStream(newCont);return std::move(newStream);}//复制JavaStyleStream copy() {Cont<Tp, Alloc> newCont;std::copy(_container.begin(), _container.end(), std::back_inserter(newCont));JavaStyleStream<Cont, Tp> newStream(newCont);return newStream;}template<typename _Predicate>JavaStyleStream copy_if(_Predicate predicate) {Cont<Tp, Alloc> newCont;std::copy_if(_container.begin(), _container.end(), std::back_inserter(newCont), predicate);JavaStyleStream<Cont, Tp> newStream(newCont);return newStream;}template<typename _Integer>JavaStyleStream copy_n(_Integer integer) {Cont<Tp, Alloc> newCont;std::copy_n(_container.begin(), integer, std::back_inserter(newCont));JavaStyleStream<Cont, Tp> newStream(newCont);return newStream;}JavaStyleStream copy_backward() {Cont<Tp, Alloc> newCont;std::copy_backward(_container.begin(), _container.end(), std::back_inserter(newCont));JavaStyleStream<Cont, Tp> newStream(newCont);return newStream;}//遍历template<typename _Function>JavaStyleStream& for_each(_Function function) {std::for_each(_container.begin(), _container.end(), function);return *this;}//reduce//集合public:JavaStyleStream(Cont<Tp, Alloc>& container): _container(container){};JavaStyleStream(JavaStyleStream& stream): _container(stream._container){};JavaStyleStream(JavaStyleStream&& stream): _container(stream._container){};private:Cont<Tp, Alloc> _container;};#endif //CPPTEST_JAVASTYLESTREAM_H