Java 如何打印空字符串数组
我试图从.dat文件中读取数据,然后将它们写入.json。问题是有些人的文件中没有电子邮件。所以,我想要像这样的东西 电子邮件:[] 但是,我的代码不打印电子邮件[]Java 如何打印空字符串数组,java,json,string,arraylist,Java,Json,String,Arraylist,我试图从.dat文件中读取数据,然后将它们写入.json。问题是有些人的文件中没有电子邮件。所以,我想要像这样的东西 电子邮件:[] 但是,我的代码不打印电子邮件[] { "personCode": "2342", "firstName": "Jeff", "lastName": "Spalding", "address": { "street": "123 Friendly Street", "city": "Ottawa", "state": "ON"
{
"personCode": "2342",
"firstName": "Jeff",
"lastName": "Spalding",
"address": {
"street": "123 Friendly Street",
"city": "Ottawa",
"state": "ON",
"zip": "K1A 0G9",
"country": "Canada"
}
}
我的代码:
String[] email = null;
String[] emailTokens = data[3].split(",");
for (int i = 0; i < emailTokens.length; i++) {
email = emailTokens;
}
Person person = new Person(personCode, firstName, lastName, address, email);
personList.add(person);
有什么想法吗?谢谢 你的循环没有意义:
for (int i = 0; i < emailTokens.length; i++) {
email = emailTokens; // Here you assign the some emailTokens N times.
}
关于您关于JSON中丢失电子邮件的问题,请尝试传递空数组:
String[] email = data[3].split(",");
if (email == null) {
email = new String[0];
}
为什么你认为你需要空邮件字段?您不能检查相应的JavaJSON对象中的字段是否为空吗?谢谢。我通过使用ArrayList emailList=new ArrayList找到了另一种方法;如果data.length==4。
String[] email = data[3].split(",");
String[] email = data[3].split(",");
if (email == null) {
email = new String[0];
}