import java.io.BufferedReader; import java.io.File; import java.io.FileReader; import java.io.FileWriter;public class FileOperate { public static void main(String[] args) throws Exception {
BufferedReader reader = new BufferedReader( new FileReader(new File("C:\\test.txt"))); StringBuffer sb = new StringBuffer(); String line = reader.readLine(); while(line!=null) { sb.append(line+"\n"); line = reader.readLine(); }
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;public class FileOperate {
public static void main(String[] args) throws Exception {
BufferedReader reader = new BufferedReader( new FileReader(new File("C:\\test.txt")));
StringBuffer sb = new StringBuffer();
String line = reader.readLine();
while(line!=null) {
sb.append(line+"\n");
line = reader.readLine();
}
reader.close();
FileWriter wr = new FileWriter(new File("C:\\test.txt") , false);
System.out.println(sb.toString().toUpperCase());
wr.write(sb.toString().toUpperCase());
wr.flush();
wr.close();
}
}
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