Question

我有一个json对象类型arraylist，并且jsonobject包含字符串和布尔值。现在我的要求是按顺序设置具有真实值的arraylist。将所有包含真实值的jsonobject放在顶部，所以我该如何更改arraylist的顺序按特定值。假设我有清单 {matched：true}，{matched：false}，{matched：true}，{matched：false}，{matched：false}，{matched：true}。但我想要清单 {matched：true}，{matched：true}，{matched：true}，{matched：false}，{matched：false}，{matched：false}。使用langugae Java。

Answer 1

在科特林：

val list = arrayListOf(false, true, false, true, false)
    list.sortBy { it == false }

输出：

[true, true, false, false, false]

这是一个示例，如果我们要根据对象进行排序：

// Your model class
class SomeObject(var value: String, var state: Boolean)
...

val list = arrayListOf<SomeObject>(
        SomeObject("some value", false),
        SomeObject("some value2", true),
        SomeObject("some value3", false),
        SomeObject("some value4", false),
        SomeObject("some value5", true))

    list.sortBy { it.state == false }

在Java中：

// Model -> 

public class SomeObject {

private String name;
private Boolean state;

public SomeObject(String name, Boolean state) {
    this.name = name;
    this.state = state;
}

public String getName() {
    return name;
}

public void setName(String name) {
    this.name = name;
}

public Boolean getState() {
    return state;
}

public void setState(Boolean state) {
    this.state = state;
}
}

...
    ArrayList<SomeObject> list = new ArrayList<>();
    list.add(new SomeObject("some value", false));
    list.add(new SomeObject("some value2", true));
    list.add(new SomeObject("some value3", false));
    list.add(new SomeObject("some value4", false));
    list.add(new SomeObject("some value5", true));

    list.sort((o1, o2) -> Boolean.compare(!o1.getState(), !o2.getState()));
    list.forEach((it) -> System.out.println(it.getState()));

输出：

[true, true, false, false, false]

通过特定值更改Arraylist顺序

1 个答案: