天天看點

java 儲存和讀取本地json檔案

儲存資料到本地檔案

  1. private void saveDataToFile(String fileName,String data) {
  2. BufferedWriter writer = null;
  3. File file = new File("d:\\"+ fileName + ".json");
  4. //如果檔案不存在,則建立一個
  5. if(!file.exists()){
  6. try {
  7. file.createNewFile();
  8. } catch (IOException e) {
  9. e.printStackTrace();
  10. }
  11. }
  12. //寫入
  13. try {
  14. writer = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(file,false), "UTF-8"));
  15. writer.write(data);
  16. } catch (IOException e) {
  17. e.printStackTrace();
  18. }finally {
  19. try {
  20. if(writer != null){
  21. writer.close();
  22. }
  23. } catch (IOException e) {
  24. e.printStackTrace();
  25. }
  26. }
  27. System.out.println("檔案寫入成功!");
  28. }

取資料

  1. private String getDatafromFile(String fileName) {
  2. String Path="d:\\" + fileName+ ".json";
  3. BufferedReader reader = null;
  4. String laststr = "";
  5. try {
  6. FileInputStream fileInputStream = new FileInputStream(Path);
  7. InputStreamReader inputStreamReader = new InputStreamReader(fileInputStream, "UTF-8");
  8. reader = new BufferedReader(inputStreamReader);
  9. String tempString = null;
  10. while ((tempString = reader.readLine()) != null) {
  11. laststr += tempString;
  12. }
  13. reader.close();
  14. } catch (IOException e) {
  15. e.printStackTrace();
  16. } finally {
  17. if (reader != null) {
  18. try {
  19. reader.close();
  20. } catch (IOException e) {
  21. e.printStackTrace();
  22. }
  23. }
  24. }
  25. return laststr;
  26. }