Google Guava 常用集合方法
/**
* Author: momo
* Date: 2018/6/7
* Description:
*/
public class ListTest {
public static void main(String[] args) {
/**List的常见用法*/
//构造list
List<Integer> list1 = Lists.newArrayList(1,2,3,4,5,6,7,8,9);
System.out.println(list1);
//反转list
List<Integer> reverseList1 = Lists.reverse(list1);
System.out.println(reverseList1);
//切割集合
List<List<Integer>> partition = Lists.partition(list1, 4);
partition.stream().forEach(list->System.out.println(list));
//拷贝为不可变集合
List list2 = new ArrayList();
list2.add(11);
list2.add(41);
list2.add(51);
list2.add(12);
ImmutableList immutableList = ImmutableList.copyOf(list2);
//创建不可变集合
ImmutableList<Integer> imList = ImmutableList.of(1, 2, 4, 12);
//获取不可变字符集合
ImmutableList<Character> asff = Lists.charactersOf("asff");
asff.stream().forEach(character -> System.out.println(character));
/**Map的常见用法*/
Map<String,Object> leftMap = ImmutableMap.of("name", "汪", "age", 18, "address", "陕西", "city", "西安","love","张");
Map<String,Object> rightMap = ImmutableMap.of("name", "张", "age", 16, "address", "陕西", "city", "西安","home","美国");
MapDifference<String, Object> deffMap = Maps.difference(leftMap, rightMap);
//相同的
Map<String, Object> map = deffMap.entriesInCommon();
System.out.println("相同的:"+map);
//同key不同value
Map<String, MapDifference.ValueDifference<Object>> stringValueDifferenceMap = deffMap.entriesDiffering();
System.out.println("同key不同value:"+stringValueDifferenceMap);
//仅仅左边有的
Map<String, Object> onlyLeft = deffMap.entriesOnlyOnLeft();
System.out.println("仅仅左边有的:"+onlyLeft);
//仅仅右边有的
Map<String, Object> onlyRight = deffMap.entriesOnlyOnRight();
System.out.println("仅仅右边有的:"+onlyRight);
/**BiMap*/
BiMap<Object, Object> biMap = HashBiMap.create();
biMap.put("张三",54);
biMap.put("李四",23);
biMap.put("程思",33);
biMap.put("吴楠",16);
//key相同value不同,后面的会覆盖前面的
biMap.put("吴楠",46);
//启动程序会报错 java.lang.IllegalArgumentException: value already present: 23
//biMap.put("张刚",23);
//强行添加,会覆盖
//biMap.forcePut("张刚",23);
System.out.println(biMap);
//反转 key和value反转
BiMap<Object, Object> inverseMap = biMap.inverse();
System.out.println(inverseMap);
}
}
结果:
[1, 2, 3, 4, 5, 6, 7, 8, 9]
[9, 8, 7, 6, 5, 4, 3, 2, 1]
[1, 2, 3, 4]
[5, 6, 7, 8]
[9]
a
s
f
f
相同的:{address=陕西, city=西安}
同key不同value:{name=(汪, 张), age=(18, 16)}
仅仅左边有的:{love=张}
仅仅右边有的:{home=美国}
{张三=54, 李四=23, 程思=33, 吴楠=46}
{54=张三, 23=李四, 33=程思, 46=吴楠}
初始化
Map<String, String> statusMap = ImmutableMap.<String, String>builder()
.put("1", "待签署")
.put("2", "签署中")
.put("3", "已签署")
.put("4", "已拒签")
.put("5", "已过期")
.put("6", "已撤销")
.put("7", "待填写")
.put("8", "填写中")
.build();