java 实验 输入/输出流

java 实验 输入/输出流

1. 获取文件属性
   在操作系统平台中文件是数据的存储单位，每个文件都有不同的属性。在Windows操作，系统中可以通过文件的属性对话框查看其对应的属性信息。本实例通过程序编码也实现了该功能，即获取文件大小、创建时间、路径等属性，效果图如下图所示

import java.awt.BorderLayout;
import java.awt.FlowLayout;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.File;
import java.sql.Date;

import javax.swing.JButton;
import javax.swing.JCheckBox;
import javax.swing.JFileChooser;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;

public class ModifyFileAttribute extends JFrame {

    private static final long serialVersionUID = 1L;
    private JPanel jContentPane = null;
    private JPanel jPanel = null;
    private JPanel jPanel1 = null;
    private JButton jButton = null;
    private JLabel fileLabel = null;
    private JLabel jLabel = null;
    private JLabel jLabel1 = null;
    private JLabel jLabel2 = null;
    private JLabel jLabel3 = null;
    private JTextField sizeField = null;
    private JTextField pathField = null;
    private JTextField uriField = null;
    private JTextField modifyDateField = null;
    private JCheckBox readCheckBox = null;
    private JCheckBox writeCheckBox = null;
    private JCheckBox hideCheckBox = null;

    /**
     * This is the default constructor
     */
    public ModifyFileAttribute() {
        super();
        initialize();
    }

    /**
     * This method initializes jPanel
     *
     * @return javax.swing.JPanel
     */
    private JPanel getJPanel() {
        if (jPanel == null) {
            FlowLayout flowLayout = new FlowLayout();
            flowLayout.setVgap(0);
            jPanel = new JPanel();
            jPanel.setLayout(flowLayout);
            jPanel.add(getReadCheckBox(), null);
            jPanel.add(getWriteCheckBox(), null);
            jPanel.add(getHideCheckBox(), null);
        }
        return jPanel;
    }

    /**
     * This method initializes jPanel1
     *
     * @return javax.swing.JPanel
     */
    private JPanel getJPanel1() {
        if (jPanel1 == null) {
            GridBagConstraints gridBagConstraints8 = new GridBagConstraints();
            gridBagConstraints8.fill = GridBagConstraints.HORIZONTAL;
            gridBagConstraints8.gridy = 4;
            gridBagConstraints8.weightx = 1.0;
            gridBagConstraints8.insets = new Insets(0, 5, 5, 0);
            gridBagConstraints8.gridx = 1;
            GridBagConstraints gridBagConstraints7 = new GridBagConstraints();
            gridBagConstraints7.fill = GridBagConstraints.HORIZONTAL;
            gridBagConstraints7.gridy = 3;
            gridBagConstraints7.weightx = 1.0;
            gridBagConstraints7.insets = new Insets(0, 5, 5, 0);
            gridBagConstraints7.gridx = 1;
            GridBagConstraints gridBagConstraints6 = new GridBagConstraints();
            gridBagConstraints6.fill = GridBagConstraints.HORIZONTAL;
            gridBagConstraints6.gridy = 2;
            gridBagConstraints6.weightx = 1.0;
            gridBagConstraints6.insets = new Insets(0, 5, 5, 0);
            gridBagConstraints6.gridx = 1;
            GridBagConstraints gridBagConstraints5 = new GridBagConstraints();
            gridBagConstraints5.fill = GridBagConstraints.HORIZONTAL;
            gridBagConstraints5.gridy = 1;
            gridBagConstraints5.weightx = 1.0;
            gridBagConstraints5.insets = new Insets(0, 5, 5, 0);
            gridBagConstraints5.gridx = 1;
            GridBagConstraints gridBagConstraints4 = new GridBagConstraints();
            gridBagConstraints4.gridx = 0;
            gridBagConstraints4.gridy = 3;
            jLabel3 = new JLabel();
            jLabel3.setText("URI路径");
            GridBagConstraints gridBagConstraints3 = new GridBagConstraints();
            gridBagConstraints3.gridx = 0;
            gridBagConstraints3.gridy = 1;
            jLabel2 = new JLabel();
            jLabel2.setText("文件大小");
            GridBagConstraints gridBagConstraints2 = new GridBagConstraints();
            gridBagConstraints2.gridx = 0;
            gridBagConstraints2.gridy = 4;
            jLabel1 = new JLabel();
            jLabel1.setText("最后修改日期");
            GridBagConstraints gridBagConstraints11 = new GridBagConstraints();
            gridBagConstraints11.gridx = 0;
            gridBagConstraints11.gridy = 2;
            jLabel = new JLabel();
            jLabel.setText("文件路径");
            GridBagConstraints gridBagConstraints1 = new GridBagConstraints();
            gridBagConstraints1.gridx = 1;
            gridBagConstraints1.fill = GridBagConstraints.HORIZONTAL;
            gridBagConstraints1.weightx = 1.0;
            gridBagConstraints1.insets = new Insets(0, 5, 0, 0);
            gridBagConstraints1.gridy = 0;
            fileLabel = new JLabel();
            fileLabel.setText("文件名");
            GridBagConstraints gridBagConstraints = new GridBagConstraints();
            gridBagConstraints.gridx = 0;
            gridBagConstraints.insets = new Insets(0, 5, 0, 0);
            gridBagConstraints.gridy = 0;
            jPanel1 = new JPanel();
            jPanel1.setLayout(new GridBagLayout());
            jPanel1.add(getJButton(), gridBagConstraints);
            jPanel1.add(fileLabel, gridBagConstraints1);
            jPanel1.add(jLabel, gridBagConstraints11);
            jPanel1.add(jLabel1, gridBagConstraints2);
            jPanel1.add(jLabel2, gridBagConstraints3);
            jPanel1.add(jLabel3, gridBagConstraints4);
            jPanel1.add(getSizeField(), gridBagConstraints5);
            jPanel1.add(getPathField(), gridBagConstraints6);
            jPanel1.add(getUriField(), gridBagConstraints7);
            jPanel1.add(getModifyDateField(), gridBagConstraints8);
        }
        return jPanel1;
    }

    /**
     * 选择文件按钮
     *
     * @return javax.swing.JButton
     */
    private JButton getJButton() {
        if (jButton == null) {
            jButton = new JButton();
            jButton.setText("选择文件");
            // 添加按钮事件监听器
            jButton.addActionListener(new ActionListener() {
                public void actionPerformed(ActionEvent e) {
                    // 创建文件选择器
                    JFileChooser chooser = new JFileChooser();
                    // 显示文件打开对话框
                    chooser.showOpenDialog(ModifyFileAttribute.this);
                    File file = chooser.getSelectedFile();// 获取选择文件
                    fileLabel.setText(file.getName());// 显示文件名称
                    sizeField.setText(file.length() + "");// 显示文件大小
                    pathField.setText(file.getPath());// 显示文件路径
                    pathField.select(0, 0);
                    uriField.setText(file.toURI() + "");// 显示文件的URI路径
                    uriField.select(0, 0);
                    // 显示文件最后修改时间
                    modifyDateField.setText(new Date(file.lastModified()) + "");
                    // 显示可读属性
                    readCheckBox.setSelected(file.canRead());
                    // 显示可写属性
                    writeCheckBox.setSelected(file.canWrite());
                    // 显示隐藏属性
                    hideCheckBox.setSelected(file.isHidden());
                }
            });
        }
        return jButton;
    }

    /**
     * This method initializes sizeField
     *
     * @return javax.swing.JTextField
     */
    private JTextField getSizeField() {
        if (sizeField == null) {
            sizeField = new JTextField();
        }
        return sizeField;
    }

    /**
     * This method initializes pathField
     *
     * @return javax.swing.JTextField
     */
    private JTextField getPathField() {
        if (pathField == null) {
            pathField = new JTextField();
        }
        return pathField;
    }

    /**
     * This method initializes uriField
     *
     * @return javax.swing.JTextField
     */
    private JTextField getUriField() {
        if (uriField == null) {
            uriField = new JTextField();
        }
        return uriField;
    }

    /**
     * This method initializes modifyDateField
     *
     * @return javax.swing.JTextField
     */
    private JTextField getModifyDateField() {
        if (modifyDateField == null) {
            modifyDateField = new JTextField();
        }
        return modifyDateField;
    }

    /**
     * This method initializes readCheckBox
     *
     * @return javax.swing.JCheckBox
     */
    private JCheckBox getReadCheckBox() {
        if (readCheckBox == null) {
            readCheckBox = new JCheckBox();
            readCheckBox.setText("可读");
        }
        return readCheckBox;
    }

    /**
     * This method initializes writeCheckBox
     *
     * @return javax.swing.JCheckBox
     */
    private JCheckBox getWriteCheckBox() {
        if (writeCheckBox == null) {
            writeCheckBox = new JCheckBox();
            writeCheckBox.setText("可写");
        }
        return writeCheckBox;
    }

    /**
     * This method initializes hideCheckBox
     *
     * @return javax.swing.JCheckBox
     */
    private JCheckBox getHideCheckBox() {
        if (hideCheckBox == null) {
            hideCheckBox = new JCheckBox();
            hideCheckBox.setText("隐藏");
        }
        return hideCheckBox;
    }

    /**
     * @param args
     */
    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                ModifyFileAttribute thisClass = new ModifyFileAttribute();
                thisClass.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                thisClass.setVisible(true);
            }
        });
    }

    /**
     * This method initializes this
     *
     * @return void
     */
    private void initialize() {
        this.setSize(400, 226);
        this.setResizable(false);
        this.setContentPane(getJContentPane());
        this.setTitle("读取文件属性");
    }

    /**
     * This method initializes jContentPane
     *
     * @return javax.swing.JPanel
     */
    private JPanel getJContentPane() {
        if (jContentPane == null) {
            BorderLayout borderLayout = new BorderLayout(10,20);
            borderLayout.setVgap(0);
            borderLayout.setHgap(0);
            jContentPane = new JPanel();
            jContentPane.setLayout(borderLayout);
            jContentPane.add(getJPanel(), BorderLayout.SOUTH);
            jContentPane.add(getJPanel1(), BorderLayout.CENTER);
        }
        return jContentPane;
    }

}

2. (简答题)

请执行声音文件的复制，复制的声音文件可自行决定，复制来源与目的声音文件的文件名都由屏幕输入。

import java.io.*;

 public class FileCopy {
public static void main(String[] args) {
        File sourceFile = new File("d:/1.mp3");//源文件
        File targetFile = new File("d:/3.mp3");//目标文件
        byte[] buf = new byte[1024];//缓冲区的大小
        if(!sourceFile.exists()){ //判断源文件是否存在，不存在就退出该程序
            System.out.println("源文件不存在");
            return;
            }
        if(targetFile.exists()){//判断目标文件时候存在，存在就删除掉
            targetFile.delete();
            }
        try {
            targetFile.createNewFile();//创建空的目标文件
            } catch (IOException e) {
            e.printStackTrace();
            }
        try {
            FileInputStream fis = new FileInputStream(sourceFile);//获取源文件的输入流
            FileOutputStream fos = new FileOutputStream(targetFile);//获取目标文件的输出流
            BufferedInputStream bis = new BufferedInputStream(fis);
            BufferedOutputStream bos = new BufferedOutputStream(fos);
            int size = -1;
            while((size=bis.read(buf))!=-1){//如果返回结果为-1，就退出循环
                bos.write(buf,0,size);
                bos.flush();
                }
            fis.close();//关闭输入流
            fos.close();//关闭输出流
            } catch (Exception e) {
            e.printStackTrace();
            }
        }
}

3. (简答题) 文件A的内容如下：
   Java面向对象程序设计
   文件B的内容如下：
   作者耿祥义、张跃平
   文件C的内容如下：
   清华大学出版社出版
   请将文件A、文件B、文件C合并成一个文件，然后输出

import java.io.*;
public class MergerFiles {
    public static void main(String[] args) {
        List<String> listFiles = new ArrayList<String>();
        String filePath1="D:/1.txt";
        String filePath2="D:/2.txt";
        String filePath3="D:/3.txt";

        listFiles.add(filePath1);
        listFiles.add(filePath2);
        listFiles.add(filePath3);
        String outputFile = "D:/4.txt";
        try {
            readAndWriteFileData(listFiles, outputFile);
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
    public static void readAndWriteFileData(List<String> listFiles,String outputFilePath) throws Exception{
        File outputFile = new File(outputFilePath);
        File outputFileParentFolder = new File(outputFile.getParent());
        if(!outputFileParentFolder.exists()) {
            outputFileParentFolder.mkdirs();
        }
        FileWriter fileWriterObj = new FileWriter(outputFile);
        BufferedWriter bufferedWriterObj = new BufferedWriter(fileWriterObj);
        for(int k=0;k<listFiles.size();k++) {
            String indexFilePath = listFiles.get(k);
            System.out.println(indexFilePath);

            File oldFile = new File(indexFilePath);
            FileReader fileReaderObj = new FileReader(oldFile);
            BufferedReader bufferedReaderObj = new BufferedReader(fileReaderObj);

            String lineStr="";
            while((lineStr=bufferedReaderObj.readLine())!=null) {
                if(lineStr !="") {
                    bufferedWriterObj.write(lineStr+"\n");
                }
            }
            bufferedWriterObj.flush();
            bufferedReaderObj.close();
            fileReaderObj.close();
        }
        bufferedWriterObj.flush();
        bufferedWriterObj.close();
        fileWriterObj.close();
    }

}