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在Spring中为每个HTTP请求清除/初始化列表(集合)

collections list spring java

1

Vicky Thakor · 技术社区 · 8 年前

我在Java上工作了4年多,但对Spring来说还是新手。我面临初始化空白的问题 List 对于每一个人 PUT

public abstract class BaseX implements InterfaceX
public class DefaultX extends BaseX
public class DefaultXAndY extends DefaultX

问题:

在课堂上使用 BaseX 要求代码如下。

InterfaceX。Java语言

public interface InterfaceX {
    public void process(Long id);
    public void publish();
}

BaseX。Java语言

import java.util.ArrayList;
import java.util.List;

import org.springframework.stereotype.Component;

@Component
public abstract class BaseX implements InterfaceX{
    private List<Long> listLong = new ArrayList<Long>();

    public void addToList(Long id){
        System.out.println("Here in BaseX");
        listLong.add(id);
    }

    @Override
    public void publish() {
        System.out.println("Print list values");
        listLong.stream().forEach(System.out::println);
    }
}

默认X。Java语言

import javax.annotation.Resource;

import org.springframework.stereotype.Component;

@Component
@Resource(name = "defaultX")
public class DefaultX extends BaseX{

    @Override
    public void process(Long id) {
        //business logic
        System.out.println("Here in DefaultX");
        addToList(id);
    }
}

import javax.annotation.Resource;
import org.springframework.stereotype.Component;

@Component
@Resource(name = "defaultXAndY")
public class DefaultXAndY extends DefaultX{
    @Override
    public void process(Long id) {
        //Business logic different than X
        System.out.println("Here in DefaultXAndY");
        id = id + 10;
        super.process(id);
    }
}

测试服务。Java语言

public interface TestService {
    public void testServiceMethod(Long id);
}

TestServiceImpl

import javax.annotation.Resource;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import com.orderhive.inventory.service.TestService;
import com.orderhive.inventory.stock.InterfaceX;

@Service
public class TestServiceImpl implements TestService{

    @Autowired
    @Resource(name = "defaultXAndY")
    private InterfaceX interfaceX; 

    @Override
    public void testServiceMethod(Long id) {
        interfaceX.process(id);
        interfaceX.publish();
        System.out.println("API call finished for id: " + id);
        System.out.println("--------------------------------");
    }
}

TestRestController

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;

import com.orderhive.inventory.service.TestService;

@RestController
@RequestMapping("/test")
public class TestRestController {

    @Autowired
    private TestService testService; 

    @RequestMapping(method = RequestMethod.PUT, value = "/number/{id}")
    void stockUpdate(@PathVariable Long id){
        testService.testServiceMethod(id);
    }
}

输出

**PUT: localhost:8080/test/number/1**

Here in DefaultXAndY
Here in DefaultX
Here in BaseX
Print list values
11
API call finished for id: 1
--------------------------------
**PUT: localhost:8080/test/number/2**

Here in DefaultXAndY
Here in DefaultX
Here in BaseX
Print list values
11
12
API call finished for id: 2
--------------------------------

列表

===========================================================

以下改变对我来说很有效,但这是最佳做法吗?

远离的 @Component 从…起 BaseX公司
@Scope("request") 添加到 DefaultX 和 DefaultXAndY
@Scope(value = "request", proxyMode = ScopedProxyMode.TARGET_CLASS) 添加到 TestServiceImpl 由@anatoly shamov建议

解决方案:

远离的 @组件 从…起 BaseX公司
添加到 默认X DefaultXAndY

1 回复 | 直到 8 年前

1

Anatoly Shamov Fildor 8 年前

BaseX 是一个豆子 singleton scope (默认情况下)。这意味着只有一个 BaseX公司 你应该抽象 listLong 用单独的bean表示 request scope . 将为每个HTTP请求创建该bean的新实例。

@Component
@Scope(value = "request", proxyMode= ScopedProxyMode.TARGET_CLASS)
public class ListX {
    private List<Long> listLong = new ArrayList<Long>();

    public List<Long> getListLong() {
        return listLong;
    }

    public void setListLong(List<Long> listLong) {
        this.listLong = listLong;
    }
}

在as中使用 listLong公司

@Component
public abstract class BaseX implements InterfaceX{

    @Autowired
    ListX listHolder;

    public void addToList(Long id){
        System.out.println("Here in BaseX");
        listHolder.getListLong().add(id);
    }

    @Override
    public void publish() {
        System.out.println("Print list values");
        listHolder.getListLong().stream().forEach(System.out::println);
    }
}