Java 方法结束(@Autowire)后松开已设置的实例/null
我试图设置解析器依赖于URI。 我正在调试它。 当条件为OK时,将设置my parserParent,但在setParser()方法的末尾,parserParent再次为null。我试图在继承类中结合asigning@Autowired注释,但总是得到相同的NullPointer错误。 如何修复它 问题出在哪里Java 方法结束(@Autowire)后松开已设置的实例/null,java,spring,autowired,Java,Spring,Autowired,我试图设置解析器依赖于URI。 我正在调试它。 当条件为OK时,将设置my parserParent,但在setParser()方法的末尾,parserParent再次为null。我试图在继承类中结合asigning@Autowired注释,但总是得到相同的NullPointer错误。 如何修复它 问题出在哪里 import org.springframework.beans.factory.annotation.Autowired; import org.springframework.web
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;
import pl.manciak.excelparser.ParseAndSave.ParseCsvAndSaveToDB;
import pl.manciak.excelparser.ParseAndSave.ParseXlsxAndSaveToDb;
import pl.manciak.excelparser.ParseAndSave.ParserParent;
import java.io.IOException;
@RestController
public class RestClientSave {
private ParserParent parserParent;
private ParseCsvAndSaveToDB parseCsvAndSaveToDB;
private ParseXlsxAndSaveToDb parseXlsxAndSaveToDb;
private String whichParser= "csv"; //HARDCODED FOR SIMPLICITY
@Autowired
public void setParser( ParseCsvAndSaveToDB parseCsvAndSaveToDB,
ParseXlsxAndSaveToDb parseXlsxAndSaveToDb) {
if (whichParser.equals("csv")) {
parserParent = parseCsvAndSaveToDB; // HERE PARSER IS SETTED
}else if(whichParser.equals("xlsx")) {
this.parserParent = parseXlsxAndSaveToDb;
}
}
@GetMapping("/save/{whichParser}")
public String save(@PathVariable String whichParser) throws IOException {
this.whichParser= whichParser;
setParser( parseCsvAndSaveToDB, parseXlsxAndSaveToDb); // HERE IS AGAIN NULL
parserParent.save();
return "data saved";
}
}
解析器的父类
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import pl.manciak.excelparser.DataService;
import pl.manciak.excelparser.Entity.LinesEntity;
import pl.manciak.excelparser.Entity.MapEntity;
import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
@Service
public class ParserParent {
protected DataService dataService;
protected LinesEntity linesEntity;
protected ArrayList<String> list;
protected HashMap<Long, LinesEntity> xlsMapped = new HashMap<>();
protected MapEntity mapEntity = new MapEntity();
@Autowired
public ParserParent(DataService dataService ) {
this.dataService = dataService;
}
public void save() throws IOException {}
}
import org.springframework.beans.factory.annotation.Autowired;
导入org.springframework.stereotype.Service;
导入pl.manciak.excelparser.DataService;
导入pl.manciak.excelparser.Entity.LinesEntity;
导入pl.manciak.excelparser.Entity.MapEntity;
导入java.io.IOException;
导入java.util.ArrayList;
导入java.util.HashMap;
@服务
公共类ParserParent{
受保护的数据服务数据服务;
受保护的线人线人;
受保护的数组列表;
受保护的HashMap xlsmap=新HashMap();
受保护的MapEntity MapEntity=新MapEntity();
@自动连线
公共ParserParent(数据服务数据服务){
this.dataService=dataService;
}
public void save()引发IOException{}
}
儿童班
package pl.manciak.excelparser.ParseAndSave;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import pl.manciak.excelparser.DataService;
import pl.manciak.excelparser.Entity.LinesEntity;
import java.io.*;
import java.util.ArrayList;
import java.util.Collections;
@Service
public class ParseCsvAndSaveToDB extends ParserParent{
@Autowired
public ParseCsvAndSaveToDB(DataService dataService) {
super(dataService);
}
public void save() throws IOException {
//Stream to Read Csv file
FileReader fileReader = new FileReader("usda_sample.csv");
BufferedReader br = new BufferedReader(fileReader);
//read first line
String line = br.readLine();
long mapKey = 0;
while (line != null) {
linesEntity = new LinesEntity(); // create a new LinesEntity for this loop execution
list = new ArrayList<>();
Collections.addAll(list, line.split(","));
line = br.readLine();
linesEntity.setSingleLine(new ArrayList<>(list));
dataService.saveOne(linesEntity);
xlsMapped.put(mapKey, linesEntity);
mapKey++;
}
mapEntity.setMapa(xlsMapped);
System.out.println(xlsMapped);
dataService.save(mapEntity);
}
package pl.manciak.excelparser.ParseAndSave;
导入org.springframework.beans.factory.annotation.Autowired;
导入org.springframework.stereotype.Service;
导入pl.manciak.excelparser.DataService;
导入pl.manciak.excelparser.Entity.LinesEntity;
导入java.io.*;
导入java.util.ArrayList;
导入java.util.Collections;
@服务
公共类ParseCsvAndSaveToDB扩展了ParserParent{
@自动连线
公共ParseCsvAndSaveToDB(数据服务数据服务){
超级(数据服务);
}
public void save()引发IOException{
//流来读取Csv文件
FileReader FileReader=新的FileReader(“usda_sample.csv”);
BufferedReader br=新的BufferedReader(文件读取器);
//读第一行
String line=br.readLine();
长映射键=0;
while(行!=null){
linesEntity=newlinesentity();//为此循环执行创建一个新的linesEntity
列表=新的ArrayList();
Collections.addAll(list,line.split(“,”);
line=br.readLine();
linesEntity.setSingleLine(新数组列表(list));
dataService.saveOne(linesEntity);
xlsmaped.put(映射键,linesEntity);
mapKey++;
}
setMapa(xlsmap);
系统输出打印LN(XLS映射);
dataService.save(mapEntity);
}
问题已解决!:D
以下是代码:
@RestController
public class RestClientSave {
ParseCsvAndSaveToDB parseCsvAndSaveToDB;
ParseXlsxAndSaveToDb parseXlsxAndSaveToDb;
@Autowired
public RestClientSave(ParseCsvAndSaveToDB parseCsvAndSaveToDB, ParseXlsxAndSaveToDb parseXlsxAndSaveToDb) {
this.parseCsvAndSaveToDB = parseCsvAndSaveToDB;
this.parseXlsxAndSaveToDb = parseXlsxAndSaveToDb;
}
public ParserParent setParser(ParseCsvAndSaveToDB parseCsvAndSaveToDB,
ParseXlsxAndSaveToDb parseXlsxAndSaveToDb,
String whichParser) {
ParserParent parserParent = null;
if (whichParser.equals("csv")) {
return parserParent = parseCsvAndSaveToDB;
}else if(whichParser.equals("xlsx")) {
return parserParent = parseXlsxAndSaveToDb;
}
return parserParent;
}
@GetMapping("/save/{whichParser}")
public String save(@PathVariable String whichParser) throws IOException {
ParserParent parent = setParser( parseCsvAndSaveToDB, parseXlsxAndSaveToDb, whichParser);
parent.save();
return "data saved";
}
}