关于JSON字符串
向客户端返回JSON字符串有两种方法:
1.纯手工拼接:
result.append("{");
result.append("\"timu\":\""+timu+"\"");
result.append(",");
result.append("\"id\":\""+id3+"\"");
result.append("}");
2.引入jar包(jackson-all-1.7.6.jar)然后根据对象的get方法生成
package com.lhp.unit;
import java.io.IOException;
import java.util.Arrays;
import java.util.List;
import org.codehaus.jackson.JsonGenerationException;
import org.codehaus.jackson.annotate.JsonIgnore;
import org.codehaus.jackson.map.JsonMappingException;
import org.codehaus.jackson.map.ObjectMapper;
public class Customer
{
public Customer(String name, String age)
{
super();
this.name = name;
this.age = age;
}
private String name;
private String age;
public String getName()
{
return name;
}
public void setName(String name)
{
this.name = name;
}
public String getAge()
{
return age;
}
public void setAge(String age)
{
this.age = age;
}
public String getCity()
{
return "beijing";
}
@JsonIgnore
public String getBrith()
{
return "01-22";
}
public static void main(String[] args) throws JsonGenerationException, JsonMappingException, IOException
{
//1.导入jar包(jackson-all-1.7.6.jar)
//2.创建ObjectMapper对象
ObjectMapper mapper =new ObjectMapper();
//3.调用mapper的WriteValueAsString()方法把一个对象转化成json字符串
Customer customer=new Customer("李营", "20");
String jsonStr=mapper.writeValueAsString(customer);
System.out.println(jsonStr);
//4.注意:JakeSon对象使用get方法来定位JSON对象的属性
//5.通过添加注解(@JsonIgnore)来忽略某一个get定义的属性
//转集合:
List<Customer> customers = Arrays.asList(customer,new Customer("yue", "19"));
jsonStr = mapper.writeValueAsString(customers);
System.out.println(jsonStr);
}
}