用JAVA实现文本形式的树状结构显示

importjava.util.ArrayList;
importjava.util.List;

publicclassFolder...{
publicFolder(Stringtitle)...{
this.title=title;
}

privateStringtitle;

privateListchildren=newArrayList();

publicvoidaddChild(Folderf)...{
children.add(f);
}

publicListgetChildren()...{
returnchildren;
}

publicvoidsetChildren(Listchildren)...{
this.children=children;
}

publicStringgetTitle()...{
returntitle;
}

publicvoidsetTitle(Stringtitle)...{
this.title=title;
}

publicStringtoString(StringlftStr,Stringappend)...{
StringBuilderb=newStringBuilder();
b.append(append+title);
b.append(" ");
if(children.size()>0)...{
for(inti=0;i<children.size()-1;i++)...{
b.append(lftStr+((Folder)children.get(i)).toString(lftStr+"│","├"));
}
b.append(lftStr+((Folder)children.get(children.size()-1)).toString(lftStr+"","└"));
}
returnb.toString();
}

publicstaticvoidmain(String[]args)...{
Folderroot=newFolder("菜单列表");
Folderf1=newFolder("开始菜单");
root.addChild(f1);
Folderf1_1=newFolder("程序");
f1.addChild(f1_1);
Folderf1_1_1=newFolder("附件");
f1_1.addChild(f1_1_1);
Folderf1_1_1_1=newFolder("娱乐");
f1_1_1.addChild(f1_1_1_1);
Folderf1_1_1_2=newFolder("娱乐2");
f1_1_1.addChild(f1_1_1_2);
Folderf1_2=newFolder("辅助工具");
f1.addChild(f1_2);
Folderf2=newFolder("MyDocuments");
root.addChild(f2);
Folderf3=newFolder("MyDocuments2");
root.addChild(f3);
System.out.println(root.toString("",""));
}
}