字符通向字节流的桥梁---- OutputStreamWriter

OutputStream out = System.out;

OutputStreamWriter osw = new OutputStreamWriter(out);

BufferedWriter w = new BufferedWriter(osw);

osw.write(line.toUpperCase());

osw.newLine();

osw.fulsh();

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BufferedWriter bufw = new BufferedWriter(new OutputStreamWriter(System.out));