import java.io.*;
public class LogOutputStream extends OutputStream {
private OutputStream os;
public LogOutputStream(OutputStream outputStream) {
this.os = outputStream;
}
@Override
public void write(int b) throws IOException {
this.os.write(b);
}
@Override
public void write(byte[] b) throws IOException {
System.out.println("开始了");
super.write(b);
System.out.println("结束了");
}
}
充当进度条：
package the_mass.dec
orator;
import java.io.IOException;
import java.io.OutputStream;
public class ProgressOutStream extends OutputStream {
private OutputStream os;
public ProgressOutStream(OutputStream outputStream) {
this.os=outputStream;
}
@Override
public void write(int b) throws IOException {
this.os.write(b);
}
@Override
public void write(byte[] b) throws IOException {
System.out.println(">>>>>>>>>>>>>");
super.write(b);
}
}
测试：
package the_mass.decorator;
import java.io.FileOutputStream;
import java.io.IOException;
public class Main {
public static void main(String[] args) throws IOException {
