System.out.println()输出到文件_idea system.out.println 输出txt-优快云博客

本文介绍了一种在Java中实现将标准输出同时发送到控制台和文件的方法。通过创建一个自定义的`MultiOutputStream`类继承`OutputStream`，并接收一个`OutputStream`列表作为构造参数。该类可以将写入的数据复制到列表中的每一个输出流，从而实现同时输出到多个目的地。

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import java.io.FileNotFoundException;

import java.io.PrintStream;public class TestSystemOut {public static void main(String[] args) throws FileNotFoundException {System.setOut(new PrintStream("f:/test.txt"));System.out.println("Hello World");}}

输出到多个地方.

如: console和文件

import java.io.IOException;
import java.io.OutputStream;
import java.util.List;

import org.apache.commons.collections.CollectionUtils;

public class MultiOutputStream extends OutputStream {
	private List<OutputStream> outputStreams;

	public MultiOutputStream(List<OutputStream> outputStreams) throws IOException {
		super();

		if (CollectionUtils.isEmpty(outputStreams)) {
			throw new IOException("must set one OutputStream at least!");
		}

		this.outputStreams = outputStreams;
	}

	@Override
	public void write(int b) throws IOException {
		for (OutputStream outputStream : outputStreams) {
			outputStream.write(b);
		}
	}

}

			List<OutputStream> outputStreams = new ArrayList<OutputStream>();
			outputStreams.add(System.out);
			outputStreams.add(new FileOutputStream("../test.out"));
			MultiOutputStream multiOutputStream = new MultiOutputStream(outputStreams);
			System.setOut(new PrintStream(multiOutputStream));