guava ordering

Guava introduces some new collection types that are not available in JDK, but are very useful. All these new collection types can be smoothly integrated with the collection in JDK. The Guava set accurately implements the JDK-defined interfaces. The new set defined in Guava includes:MultisetSortedMultisetMultimapListMultimapSetMultimapBiMapClassToInstanceMapTable

business are increased, and the code you write becomes less readable. Then we can consider using the bimap in guava. 　　Bimap 　　Bimap is very simple to use, for the above use of the scenario, we can use a very simple code to achieve: @Test public void Bimaptest () {bimap 　　Mandatory uniqueness of BIMAP data 　　When using Bimap, value uniqueness is required. If value is repeated, an error is thrown: java.lang.IllegalArgumentException, for example: @Test

Table 　When we need data structures with Multiple indexes, we can only use this ugly Map Output: {A=A2, B=B2, C=1=B1, 2=B2, 3=1={A=A1, B=B1, C=C1}, 2={A=A2, B=B2, C=C2}, 3={A=A3, B=B3, C=={1=A1, 2=A2, 3=A3}, B={1=B1, 2=B2, 3=B3}, C={1=C1, 2=C2, 3= Table View:RowMap () returns a Map Row (r) returns a non-null Map The column-related methods include columnMap (), columnKeySet (), and column (c ). (Column-based operations are less efficient than Row-based operations)The returned result of cellSet

1. Introduction The Guava project contains a number of core libraries that are heavily reliant on Google's Java projects, including collections, caching, primitives support, concurrency libraries, common Annotations, string processing, I/O, and so on. These high quality APIs can make your Java code more elegant and concise, making your work easier and more enjoyable. 2. Official Information Official home: Http://code.google.com/p/

In daily development, we sometimes need to construct a Map Note: It is too difficult to implement 　　Multimap The Multimap of Guava provides a data structure that conveniently maps a key to multiple values. This allows us to easily and elegantly implement the complex data structure above, so that we can focus on implementing business logic rather than on the data structure, next, let's take a look at the knowledge points of Multimap. The above code

control over the set sort;Examples are as follows:Lists.newarraylist (30, 20, 60, 80, 10);Ordering.natural (). sortedcopy (numbers); 10,20,30,60,80Ordering.natural (). Reverse (). Sortedcopy (numbers); 80,60,30,20,10Ordering.natural (). min (numbers); 10Ordering.natural (). Max (numbers); 80Lists.newarraylist (+, 10);Ordering.natural (). Nullslast (). sortedcopy (numbers); Ten, 20,30,60,80,nullOrdering.natural (). Nullsfirst (). sortedcopy (numbers); null,10,20,30,60,80public static void Testor

follows:Lists.newarraylist (30, 20, 60, 80, 10);Ordering.natural (). sortedcopy (numbers); 10,20,30,60,80Ordering.natural (). Reverse (). Sortedcopy (numbers); 80,60,30,20,10Ordering.natural (). min (numbers); 10Ordering.natural (). Max (numbers); 80Lists.newarraylist (+, 10);Ordering.natural (). Nullslast (). sortedcopy (numbers); Ten, 20,30,60,80,nullOrdering.natural (). Nullsfirst (). sortedcopy (numbers); null,10,20,30,60,80public static void Testordering (){ListNew Person (3, 1, "abc", "46

Guava However, you can search for javadoc over the Internet. This Basic utilities (Basic tool set): Used Using and avoiding null (avoid null): null Preconditions (: Common object methods (Common object method): simplifies the implementation of object methods, such as hashCode () and toString. (Note: In Native java, an object acts as a Map) Ordering: (SORT): Guava