JAVA语言复习题及答案

this.setLocationRelativeTo(null);// 设置窗口位置 this.setVisible(true);// 设置窗口可见性 this.add(text);

menuBar = new JMenuBar();

file = new JMenu(\文件\文件菜单

// 文件菜单项

fileItem1 = new JMenuItem(\新建\ fileItem2 = new JMenuItem(\打开\ fileItem3 = new JMenuItem(\关闭\ fileItem4 = new JMenuItem(\退出\

// 添加文件子菜单项 file.add(fileItem1); file.add(fileItem2); file.add(fileItem3);

file.addSeparator();// 添加分割线 file.add(fileItem4);

// 往菜单栏添加菜单项 menuBar.add(file);

this.setJMenuBar(menuBar); }

public static void main(String[] args) {

new Exam1(); } }

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bar

import java.io.BufferedReader; import java.io.File; import java.io.FileReader; import java.util.HashMap; import java.util.Iterator; import java.util.Map; import java.util.Map.Entry;

public class Exam1 {

public static void main(String[] args) Exception {

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findStringInFile(\, \); }

public static void findStringInFile(String fileName,String subStr) throws Exception { Map map = new HashMap(); FileReader fr = new FileReader(new File(fileName));

BufferedReader br = new BufferedReader(fr); String line = null; Integer count = 0;

while((line = br.readLine()) != null) { if(line.contains(subStr)) { map.put(count, line); }

count ++; }

Iterator iter = map.entrySet().iterator(); while(iter.hasNext()) {

Entry entry = (Entry) iter.next(); Object key = entry.getKey();

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Object val = entry.getValue(); System.out.println(key+\+val); }

br.close(); } }

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