使用java

Question

我创建了多个列表，如下所示

static List<String> dbName = new ArrayList<String>();
    static List<String> dbServerName = new ArrayList<String>();
    static List<String> lDbName = new ArrayList<String>();
    static List<String> lServerName = new ArrayList<String>();
    static List<String> serverName = new ArrayList<String>();
    static List<String> dbServerNameSecondary = new ArrayList<String>();

是否可以使用单个for-each循环遍历所有列表对象 如下所示

for（dbName，dbServerName ....中的项目）

我想平行迭代并将获得的值放在下面的查询中

String drop =＆＃34; Drop table if exists＆＃34; + hive_db +＆＃34;。＆＃34; +＆＃34; IB_C3 _＆＃34; + dbName +＆＃34; _＆＃34; + DBSERVERNAME;

Answer 1

是的，假设列表大小相同，您可以使用标准for循环在 parallel 中迭代它们：

static List<String> dbName = new ArrayList<String>();
static List<String> dbServerName = new ArrayList<String>();
static List<String> lDbName = new ArrayList<String>();
static List<String> lServerName = new ArrayList<String>();
static List<String> serverName = new ArrayList<String>();
static List<String> dbServerNameSecondary = new ArrayList<String>();

// code filling lists here

for (int i = 0; i < dbName.size(); i++) {
    // dbName.get(i)
    // ...
    // dbServerNameSecondary.get(i)
}

但是，如果列表大小相同，则建议使用Java的面向对象功能强烈。这意味着为值创建一个类。

public class Database {
    private String dbName;
    private String dbServerName;
    private String lDbName;
    private String lServerName;
    private String serverName;
    private String dbServerNameSecondary;
    // getters and setters here
}

static List<Database> databases = new ArrayList<>();

// code filling list here

for (Database database : databases) {
    // database.getDbName()
    // ...
    // database.getDbServerNameSecondary()
}