使用StringReader和StringWriter操作字串

編程舉例：寫一函數把StringReader中輸入資料流中的字串全部轉換成大寫，然後將結果寫到一個StringWriter中，然後使用這一函數將以字串全部轉成大寫。

 

package cn.itcast.stringstream;<br />import java.io.IOException;<br />import java.io.StringReader;<br />import java.io.StringWriter;<br />public class StringStreamTest {<br />public static void main(String[] args) {<br />String str = "abcdefghijklmn";<br />transform(str);<br />}<br />public static void transform(String str) {<br />StringReader sr = new StringReader(str);<br />StringWriter sw = new StringWriter();<br />char[] chars = new char[1024];<br />try {<br />int len = 0;<br />while ((len = sr.read(chars)) != -1) {<br />String strRead = new String(chars, 0, len).toUpperCase();<br />System.out.println(strRead);<br />sw.write(strRead);<br />sw.flush();<br />}<br />sr.close();<br />sw.close();<br />} catch (IOException e) {<br />e.printStackTrace();<br />} finally {<br />sr.close();<br />try {<br />sw.close();<br />} catch (IOException e) {<br />e.printStackTrace();<br />}<br />}<br />}<br />}<br />