FileInputStream is = null; FileOutputStream os = null; try{ is = new FileInputStream("hoge.txt"); InputStreamReader ir = new InputStreamReader(is,"Shift_JIS"); os = new FileOutputStream("hige.txt"); OutputStreamWriter ow = new OutputStreamWriter(os,"UTF-8"); int tmp; while((tmp = ir.read()) != -1){ ow.write(tmp); } }catch(Exception e){ e.printStackTrace(); }finally { is.close(); os.close(); } try(
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