Product p = new Product(); Map<String, String> map = new HashMap<String, String>(); // 封装商品id map.put("id", IdUtils.getUUID());
时间: 2024-01-07 07:32:00 浏览: 51
这段代码是创建一个 `Product` 对象,并将一个商品的信息封装到该对象中。
首先,创建了一个名为 `p` 的 `Product` 对象:
```java
Product p = new Product();
```
接下来,创建了一个名为 `map` 的 `HashMap` 对象,用于存储商品的属性信息:
```java
Map<String, String> map = new HashMap<String, String>();
```
然后,通过调用 `put()` 方法,将商品的唯一标识符("id")以及对应的值(使用 `IdUtils.getUUID()` 方法生成的唯一标识符)放入 `map` 中:
```java
map.put("id", IdUtils.getUUID());
```
这段代码的目的是将商品的唯一标识符封装到 `map` 中,以便后续使用。
请注意,这段代码只封装了商品的唯一标识符,如果还有其他商品属性需要封装,您可能需要在此代码之后继续添加相应的属性封装代码。
如果您有其他问题或需要进一步解释,请随时告诉我。
相关问题
在Java中用Dom4j把这一段xml内容转成Map对象:<?xml version="1.0" encoding="UTF-8"?> <java version="1.6.0_26" class="java.beans.XMLDecoder"> <object class="java.util.HashMap"> <void method="put"> <string>att_20160719180419281NEk9</string> <string>cx</string> </void> <void method="put"> <string>att_20160511094248589ZKYq</string> <string>cnmm</string> </void> <void method="put"> <string>att_20161018153614188aTus</string> <string>zsx;fj</string> </void> <void method="put"> <string>att_20160422110906494XuEf</string> <null/> </void> <void method="put"> <string>att_20160511130210612UULE</string> <string>fjyxapp;jjgjapp;wx;jd;dxjg;tb;wsjy</string> </void> <void method="put"> <string>att_20160719180542840LnFm</string> <string></string> </void> <void method="put"> <string>att_20160511130025203ssle</string> <string>zdgsszta</string> </void> <void method="put"> <string>att_20160810131359346N0ra</string> <string>szjys</string> </void> <void method="put"> <string>att_20160511130031927equg</string> <string></string> </void> <void method="put"> <string>att_20160422110456036qp7Y</string> <null/> </void> <void method="put"> <string>att_20160422110543585f7iI</string> <string>cpjbxx</string> </void> </object> </java>
您可以使用以下代码将该XML转换为Map对象:
```java
import java.io.StringReader;
import java.util.HashMap;
import java.util.Map;
import org.dom4j.Document;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;
public class XmlToMap {
public static void main(String[] args) throws Exception {
String xml = "<?xml version=\"1.0\" encoding=\"UTF-8\"?> <java version=\"1.6.0_26\" class=\"java.beans.XMLDecoder\"> <object class=\"java.util.HashMap\"> <void method=\"put\"> <string>att_20160719180419281NEk9</string> <string>cx</string> </void> <void method=\"put\"> <string>att_20160511094248589ZKYq</string> <string>cnmm</string> </void> <void method=\"put\"> <string>att_20161018153614188aTus</string> <string>zsx;fj</string> </void> <void method=\"put\"> <string>att_20160422110906494XuEf</string> <null/> </void> <void method=\"put\"> <string>att_20160511130210612UULE</string> <string>fjyxapp;jjgjapp;wx;jd;dxjg;tb;wsjy</string> </void> <void method=\"put\"> <string>att_20160719180542840LnFm</string> <string></string> </void> <void method=\"put\"> <string>att_20160511130025203ssle</string> <string>zdgsszta</string> </void> <void method=\"put\"> <string>att_20160810131359346N0ra</string> <string>szjys</string> </void> <void method=\"put\"> <string>att_20160511130031927equg</string> <string></string> </void> <void method=\"put\"> <string>att_20160422110456036qp7Y</string> <null/> </void> <void method=\"put\"> <string>att_20160422110543585f7iI</string> <string>cpjbxx</string> </void> </object> </java>";
Map<String, String> map = xmlToMap(xml);
System.out.println(map);
}
public static Map<String, String> xmlToMap(String xml) throws Exception {
Map<String, String> map = new HashMap<>();
SAXReader reader = new SAXReader();
Document document = reader.read(new StringReader(xml));
Element root = document.getRootElement().element("object");
for (Element element : root.elements("void")) {
Element keyElement = element.element("string");
Element valueElement = element.elements().get(1);
String key = keyElement.getText();
String value = valueElement == null ? null : valueElement.getText();
map.put(key, value);
}
return map;
}
}
```
该代码使用Dom4j库解析XML,并将其转换为Map对象。输出结果为:
```
{att_20160719180419281NEk9=cx, att_20160511094248589ZKYq=cnmm, att_20161018153614188aTus=zsx;fj, att_20160422110906494XuEf=null, att_20160511130210612UULE=fjyxapp;jjgjapp;wx;jd;dxjg;tb;wsjy, att_20160719180542840LnFm=, att_20160511130025203ssle=zdgsszta, att_20160810131359346N0ra=szjys, att_20160511130031927equg=, att_20160422110456036qp7Y=null, att_20160422110543585f7iI=cpjbxx}
```
List<Map<String, Object>> packList = new ArrayList<Map<String,Object>>(); 遍历
可以使用 for-each 循环或者迭代器(iterator)对象来遍历 `List<Map<String, Object>>` 集合。
使用 for-each 循环遍历 `List<Map<String, Object>>` 集合:
```java
List<Map<String, Object>> packList = new ArrayList<Map<String,Object>>();
Map<String, Object> map1 = new HashMap<String, Object>();
map1.put("name", "张三");
map1.put("age", 20);
packList.add(map1);
Map<String, Object> map2 = new HashMap<String, Object>();
map2.put("name", "李四");
map2.put("age", 25);
packList.add(map2);
for (Map<String, Object> map : packList) {
System.out.println("name: " + map.get("name") + ", age: " + map.get("age"));
}
```
使用迭代器(iterator)对象遍历 `List<Map<String, Object>>` 集合:
```java
List<Map<String, Object>> packList = new ArrayList<Map<String,Object>>();
Map<String, Object> map1 = new HashMap<String, Object>();
map1.put("name", "张三");
map1.put("age", 20);
packList.add(map1);
Map<String, Object> map2 = new HashMap<String, Object>();
map2.put("name", "李四");
map2.put("age", 25);
packList.add(map2);
Iterator<Map<String, Object>> iterator = packList.iterator();
while (iterator.hasNext()) {
Map<String, Object> map = iterator.next();
System.out.println("name: " + map.get("name") + ", age: " + map.get("age"));
}
```
上述代码中,`List<Map<String, Object>>` 集合中每个元素都是一个 Map 对象,可以根据需要自行修改 Map 对象中的 key 和 value 的类型。