Swing :对象无法转换为字符串

Question

我有一个转换问题；我的变量CodeA的类型是String

col.setCodeA((Collabo)jComboBoxAlbum.getSelectedItem());

我的错误信息是Object cannot be converted to String在这种情况下如何转换我的变量CodeA？

Collabo col = new Collabo();
        col.setCodeA((Collabo)jComboBoxAlbum.getSelectedItem());
        boolean ok = daoCol.insertCollabo(col);
        if (!ok)
            JOptionPane.showMessageDialog(null,"Insertion impossible !","Avertissement",JOptionPane.ERROR_MESSAGE);
        this.dispose();

这是我的类Collabo：

public class Collabo {
    private String codeA;
    private Musicien mutApp;
    private Instrument insApp;


    public Collabo(String codeA, Musicien mutApp, Instrument insApp) {
        this.codeA = codeA;
        this.mutApp = mutApp;
        this.insApp = insApp;
    }

    public String getCodeA() {
        return codeA;
    }

    public void setCodeA(String codeA) {
        this.codeA = codeA;
    }

    public Musicien getMutApp() {
        return mutApp;
    }

    public void setMutApp(Musicien mutApp) {
        this.mutApp = mutApp;
    }

    public Instrument getInsApp() {
        return insApp;
    }

    public void setInsApp(Instrument insApp) {
        this.insApp = insApp;
    }

    public String toString() {
        return codeA;
    }    

Answer 1

假设您的jComboBoxAlbum包含Collabo类型的对象(因为您将结果强制转换为该类型)，并且您希望将新Collabo实例的字符串设置为与所选项目中的字符串相同，则只需调用所选项目的getCodeA()方法：

Collabo col = new Collabo();
Collabo selected = (Collabo)jComboBoxAlbum.getSelectedItem();
col.setCodeA(selected.getCodeA);