java - 将对象克隆到列表中，并为每个项目更改多个值

Question

我正在尝试让我的代码将名为 primitive 的 OutputData 对象克隆到列表中，为我正在创建的每个克隆更改 int 值。这是我想出的代码:

public void fixAndSave(){
    for(int i = 1; i <= NUM_EXEC; i++){
        InputData custom = new InputData(primitive);
        for (Section s : custom.getSections()){
            if (s.getId() != 0 )
                s.setBloques(i*s.getId());
        }
        collection.add(custom);
        System.out.println("GUARDANDO DATA: " + custom.getSections().toString());

    }
    collection.forEach((InputData d) -> {
        System.out.println("DATA GUARDADO: " + d.getSections().toString());
    });
}

我的问题是，当我检查结果时，仅保存最后一个值并为每个克隆对象重复，因此我猜测我正在以某种方式复制对该对象的整个引用。我应该如何正确地做到这一点，以便每个对象都包含正确的信息？

这是该方法的输出:

//This values are correct and are the ones I want
GUARDANDO DATA: [Section [id=0, length=7.5, bloques=0], Section [id=1, length=7.5, bloques=1], Section [id=2, length=7.5, bloques=2], Section [id=3, length=7.5, bloques=3]]

GUARDANDO DATA: [Section [id=0, length=7.5, bloques=0], Section [id=1, length=7.5, bloques=2], Section [id=2, length=7.5, bloques=4], Section [id=3, length=7.5, bloques=6]]

GUARDANDO DATA: [Section [id=0, length=7.5, bloques=0], Section [id=1, length=7.5, bloques=3], Section [id=2, length=7.5, bloques=6], Section [id=3, length=7.5, bloques=9]]

GUARDANDO DATA: [Section [id=0, length=7.5, bloques=0], Section [id=1, length=7.5, bloques=4], Section [id=2, length=7.5, bloques=8], Section [id=3, length=7.5, bloques=12]]

// This values are incorrect and saved in the list
DATA GUARDADO: [Section [id=0, length=7.5, bloques=0], Section [id=1, length=7.5, bloques=4], Section [id=2, length=7.5, bloques=8], Section [id=3, length=7.5, bloques=12]]

DATA GUARDADO: [Section [id=0, length=7.5, bloques=0], Section [id=1, length=7.5, bloques=4], Section [id=2, length=7.5, bloques=8], Section [id=3, length=7.5, bloques=12]]

DATA GUARDADO: [Section [id=0, length=7.5, bloques=0], Section [id=1, length=7.5, bloques=4], Section [id=2, length=7.5, bloques=8], Section [id=3, length=7.5, bloques=12]]

DATA GUARDADO: [Section [id=0, length=7.5, bloques=0], Section [id=1, length=7.5, bloques=4], Section [id=2, length=7.5, bloques=8], Section [id=3, length=7.5, bloques=12]]

Answer 1

您需要执行深度复制，并在调用时考虑 getSections() 返回的字段:

InputData custom = new InputData(primitive);

它可能看起来像:

public InputData(OutputData outputData){
     // ...
     List<Section> copiedSections = new ArrayList<>();
     for (Section section : outputData.getSections()){
           Section copiedSection = new Section(section); // copy constructor
           copiedSections.add(copiedSection);
     }
     this.sections = copiedSections;    
}