springboot 重定向（RedirectAttributes）

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springboot 重定向（RedirectAttributes）

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相关类及接口

RedirectAttributes

public interface RedirectAttributes extends Model {

    RedirectAttributes addAttribute(String var1, @Nullable Object var2);
    RedirectAttributes addAttribute(Object var1);

    RedirectAttributes addAllAttributes(Collection<?> var1);
    RedirectAttributes mergeAttributes(Map<String, ?> var1);

    RedirectAttributes addFlashAttribute(String var1, @Nullable Object var2);
    RedirectAttributes addFlashAttribute(Object var1);

    Map<String, ?> getFlashAttributes();
}

RedirectAttributesModelMap

public class RedirectAttributesModelMap extends ModelMap implements RedirectAttributes {

    @Nullable
    private final DataBinder dataBinder;
    private final ModelMap flashAttributes;

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构造方法

    public RedirectAttributesModelMap() {
    public RedirectAttributesModelMap(@Nullable DataBinder dataBinder) {

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普通方法

    public RedirectAttributesModelMap addAttribute(String attributeName, @Nullable Object attributeValue) {
    public RedirectAttributesModelMap addAttribute(Object attributeValue) {

    public RedirectAttributesModelMap addAllAttributes(@Nullable Collection<?> attributeValues) {
    public RedirectAttributesModelMap addAllAttributes(@Nullable Map<String, ?> attributes) {
    public RedirectAttributesModelMap mergeAttributes(@Nullable Map<String, ?> attributes) {

    public RedirectAttributes addFlashAttribute(String attributeName, @Nullable Object attributeValue) {
    public RedirectAttributes addFlashAttribute(Object attributeValue) {
                              //使用该方法将对象添加到session中，重定向后删除数据

    public Map<String, ?> getFlashAttributes() {
    public Map<String, Object> asMap() {

    @Nullable
    private String formatValue(@Nullable Object value) {

    public Object put(String key, @Nullable Object value) {
    public void putAll(@Nullable Map<? extends String, ? extends Object> map) {

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示例

@RestController
public class Hello3Controller {

    @RequestMapping("/hello3")
    public ModelAndView hello3(RedirectAttributes redirectAttributes){
        ModelAndView mv=new ModelAndView();
        mv.setViewName("redirect:/redirect3");

        Person person=new Person();
        person.setName("瓜田李下");
        person.setAge(20);
        redirectAttributes.addFlashAttribute("person",person);

        redirectAttributes.addAttribute("name","瓜田李下");
        redirectAttributes.addFlashAttribute("name2","海贼王");

        return mv;
    }

    @RequestMapping("/redirect3")
    public String redirect3(String name,@ModelAttribute("name2") String name2,Person person,@ModelAttribute("person") Person person2){
        System.out.println(name+"  "+name2);
        System.out.println(person);
        System.out.println(person2);

        return "redirect3";
    }
}

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控制台输出

瓜田李下  海贼王
Person(name=瓜田李下, age=20)
Person(name=瓜田李下, age=20)

说明：使用redirectAttributes可以有效的传递pojo对象