20个非常有用的Java程序片段

淩亂°似流年 2022-03-29 15:20 303阅读 0赞

1. 字符串有整型的相互转换

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 <td> String a = String.valueOf(2);&nbsp;&nbsp; //integer to &nbsp; numeric string&nbsp; int i = Integer.parseInt(a); //numeric string to an int </td> 
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2. 向文件末尾添加内容

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 <td> BufferedWriter out = null;&nbsp; try {&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;out = new BufferedWriter(new &nbsp; FileWriter(”filename”, true));&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;out.write(”aString”);&nbsp; } catch (IOException e) {&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;// error processing code&nbsp; } finally {&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;if (out != null) {&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;out.close();&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;}&nbsp; } </td> 
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3. 得到当前方法的名字

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 <td> String methodName = Thread.currentThread().getStackTrace()[1].getMethodName(); </td> 
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4. 转字符串到日期

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 <td> &lt;span id="12_nwp" style="width: auto; &nbsp; height: auto; float: none;"&gt;&lt;a id="12_nwl" href="<a href="http://cpro.baidu.com/cpro/ui/uijs.php?adclass=0&amp;app_id=0&amp;c=news&amp;cf=1001&amp;ch=0&amp;di=128&amp;fv=20&amp;is_app=0&amp;jk=5a3764283252b2ed&amp;k=java&amp;k0=java&amp;kdi0=0&amp;luki=3&amp;mcpm=0&amp;n=10&amp;p=baidu&amp;q=06011078_cpr&amp;rb=0&amp;rs=1&amp;seller_id=1&amp;sid=edb252322864375a&amp;ssp2=1&amp;stid=9&amp;t=tpclicked3_hc&amp;td=1922429&amp;tu=u1922429&amp;u=http%3A%2F%2Fwww.admin10000.com%2Fdocument%2F6065.html&amp;urlid=0" rel="nofollow">http://cpro.baidu.com/cpro/ui/uijs.php?adclass=0&amp;app_id=0&amp;c=news&amp;cf=1001&amp;ch=0&amp;di=128&amp;fv=20&amp;is_app=0&amp;jk=5a3764283252b2ed&amp;k=java&amp;k0=java&amp;kdi0=0&amp;luki=3&amp;mcpm=0&amp;n=10&amp;p=baidu&amp;q=06011078_cpr&amp;rb=0&amp;rs=1&amp;seller_</a> <a href="http://cpro.baidu.com/cpro/ui/uijs.php?adclass=0&amp;app_id=0&amp;c=news&amp;cf=1001&amp;ch=0&amp;di=128&amp;fv=20&amp;is_app=0&amp;jk=5a3764283252b2ed&amp;k=java&amp;k0=java&amp;kdi0=0&amp;luki=3&amp;mcpm=0&amp;n=10&amp;p=baidu&amp;q=06011078_cpr&amp;rb=0&amp;rs=1&amp;seller_id=1&amp;sid=edb252322864375a&amp;ssp2=1&amp;stid=9&amp;t=tpclicked3_hc&amp;td=1922429&amp;tu=u1922429&amp;u=http%3A%2F%2Fwww.admin10000.com%2Fdocument%2F6065.html&amp;urlid=0" rel="nofollow">id=1&amp;sid=edb252322864375a&amp;ssp2=1&amp;stid=9&amp;t=tpclicked3_hc&amp;td=1922429&amp;tu=u1922429&amp;u=http%3A%2F%2Fwww%2Eadmin10000%2Ecom%2Fdocument%2F6065%2Ehtml&amp;urlid=0</a>" &nbsp; target="_blank" mpid="12" style="text-decoration: &nbsp; none;"&gt;&lt;span &nbsp; style="color:#0000ff;font-size:14px;width:auto;height:auto;float:none;"&gt;java&lt;/span&gt;&lt;/a&gt;&lt;/span&gt;.util.Date &nbsp; = java.text.DateFormat .getDateInstance().parse(date String); </td> 
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或者是：

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 <td> SimpleDateFormat format = new SimpleDateFormat( &nbsp; "dd.MM.yyyy" );&nbsp; Date date = format.parse( myString ); </td> 
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5. 使用JDBC链接Oracle

6. 把[ Java ][Java]util.Date 转成 sql.Date

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 <td> &lt;span id="11_nwp" style="width: auto; &nbsp; height: auto; float: none;"&gt;&lt;a id="11_nwl" href="<a href="http://cpro.baidu.com/cpro/ui/uijs.php?adclass=0&amp;app_id=0&amp;c=news&amp;cf=1001&amp;ch=0&amp;di=128&amp;fv=20&amp;is_app=0&amp;jk=5a3764283252b2ed&amp;k=java&amp;k0=java&amp;kdi0=0&amp;luki=3&amp;mcpm=0&amp;n=10&amp;p=baidu&amp;q=06011078_cpr&amp;rb=0&amp;rs=1&amp;seller_id=1&amp;sid=edb252322864375a&amp;ssp2=1&amp;stid=9&amp;t=tpclicked3_hc&amp;td=1922429&amp;tu=u1922429&amp;u=http%3A%2F%2Fwww.admin10000.com%2Fdocument%2F6065.html&amp;urlid=0" rel="nofollow">http://cpro.baidu.com/cpro/ui/uijs.php?adclass=0&amp;app_id=0&amp;c=news&amp;cf=1001&amp;ch=0&amp;di=128&amp;fv=20&amp;is_app=0&amp;jk=5a3764283252b2ed&amp;k=java&amp;k0=java&amp;kdi0=0&amp;luki=3&amp;mcpm=0&amp;n=10&amp;p=baidu&amp;q=06011078_cpr&amp;rb=0&amp;rs=1&amp;seller_</a> <a href="http://cpro.baidu.com/cpro/ui/uijs.php?adclass=0&amp;app_id=0&amp;c=news&amp;cf=1001&amp;ch=0&amp;di=128&amp;fv=20&amp;is_app=0&amp;jk=5a3764283252b2ed&amp;k=java&amp;k0=java&amp;kdi0=0&amp;luki=3&amp;mcpm=0&amp;n=10&amp;p=baidu&amp;q=06011078_cpr&amp;rb=0&amp;rs=1&amp;seller_id=1&amp;sid=edb252322864375a&amp;ssp2=1&amp;stid=9&amp;t=tpclicked3_hc&amp;td=1922429&amp;tu=u1922429&amp;u=http%3A%2F%2Fwww.admin10000.com%2Fdocument%2F6065.html&amp;urlid=0" rel="nofollow">id=1&amp;sid=edb252322864375a&amp;ssp2=1&amp;stid=9&amp;t=tpclicked3_hc&amp;td=1922429&amp;tu=u1922429&amp;u=http%3A%2F%2Fwww%2Eadmin10000%2Ecom%2Fdocument%2F6065%2Ehtml&amp;urlid=0</a>" &nbsp; target="_blank" mpid="11" style="text-decoration: &nbsp; none;"&gt;&lt;span style="color:#0000ff;font-size:14px;width:auto;height:auto;float:none;"&gt;java&lt;/span&gt;&lt;/a&gt;&lt;/span&gt;.util.Date &nbsp; utilDate = new java.util.Date();&nbsp; java.sql.Date sqlDate = new &nbsp; java.sql.Date(utilDate.getTime()); </td> 
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7. 使用NIO进行快速的文件拷贝

8. 创建图片的缩略图

9. 创建 JSON 格式的数据

请先阅读这篇文章 了解一些细节，

并下面这个JAR 文件：json-rpc-1.0.jar (75 kb)

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 <td> import org.json.JSONObject;&nbsp; ...&nbsp; ...&nbsp; JSONObject json = new JSONObject();&nbsp; json.put("city", "Mumbai");&nbsp; json.put("country", "India");&nbsp; &nbsp; ...&nbsp; String output = json.toString();&nbsp; ... </td> 
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10. 使用iText JAR生成PDF

阅读这篇[文章 ][Java]了解更多细节

11. HTTP 代理设置

阅读这篇 文章 了解更多细节。

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 <td> System.getProperties().put("http.proxyHost", &nbsp; "someProxyURL");&nbsp; System.getProperties().put("http.proxyPort", &nbsp; "someProxyPort");&nbsp; System.getProperties().put("http.proxyUser", &nbsp; "someUserName");&nbsp; System.getProperties().put("http.proxyPassword", &nbsp; "somePassword"); </td> 
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12. 单实例[Singleton ][Java]示例

请先阅读这篇文章 了解更多信息

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 <td> public class SimpleSingleton {&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;private static SimpleSingleton &nbsp; singleInstance =&nbsp; new SimpleSingleton();&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;//Marking default constructor &nbsp; private&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;//to avoid direct instantiation.&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;private SimpleSingleton() &nbsp; {&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;}&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;//Get instance for class &nbsp; SimpleSingleton&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;public static SimpleSingleton &nbsp; getInstance() {&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;return &nbsp; singleInstance;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;}&nbsp; } </td> 
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另一种实现

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 <td> public enum SimpleSingleton {&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;INSTANCE;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;public void doSomething() &nbsp; {&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;}&nbsp; }&nbsp; &nbsp; //Call the method from Singleton:&nbsp; SimpleSingleton.INSTANCE.doSomething(); </td> 
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13. 抓屏程序

阅读这篇文章 获得更多信息。

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 <td> import &lt;span id="8_nwp" style="width: &nbsp; auto; height: auto; float: none;"&gt;&lt;a id="8_nwl" &nbsp; href="<a href="http://cpro.baidu.com/cpro/ui/uijs.php?adclass=0&amp;app_id=0&amp;c=news&amp;cf=1001&amp;ch=0&amp;di=128&amp;fv=20&amp;is_app=0&amp;jk=5a3764283252b2ed&amp;k=java&amp;k0=java&amp;kdi0=0&amp;luki=3&amp;mcpm=0&amp;n=10&amp;p=baidu&amp;q=06011078_cpr&amp;rb=0&amp;rs=1&amp;seller_id=1&amp;sid=edb252322864375a&amp;ssp2=1&amp;stid=9&amp;t=tpclicked3_hc&amp;td=1922429&amp;tu=u1922429&amp;u=http%3A%2F%2Fwww.admin10000.com%2Fdocument%2F6065.html&amp;urlid=0" rel="nofollow">http://cpro.baidu.com/cpro/ui/uijs.php?adclass=0&amp;app_id=0&amp;c=news&amp;cf=1001&amp;ch=0&amp;di=128&amp;fv=20&amp;is_app=0&amp;jk=5a3764283252b2ed&amp;k=java&amp;k0=java&amp;kdi0=0&amp;luki=3&amp;mcpm=0&amp;n=10&amp;p=baidu&amp;q=06011078_cpr&amp;rb=0&amp;rs=1&amp;seller_</a> <a href="http://cpro.baidu.com/cpro/ui/uijs.php?adclass=0&amp;app_id=0&amp;c=news&amp;cf=1001&amp;ch=0&amp;di=128&amp;fv=20&amp;is_app=0&amp;jk=5a3764283252b2ed&amp;k=java&amp;k0=java&amp;kdi0=0&amp;luki=3&amp;mcpm=0&amp;n=10&amp;p=baidu&amp;q=06011078_cpr&amp;rb=0&amp;rs=1&amp;seller_id=1&amp;sid=edb252322864375a&amp;ssp2=1&amp;stid=9&amp;t=tpclicked3_hc&amp;td=1922429&amp;tu=u1922429&amp;u=http%3A%2F%2Fwww.admin10000.com%2Fdocument%2F6065.html&amp;urlid=0" rel="nofollow">id=1&amp;sid=edb252322864375a&amp;ssp2=1&amp;stid=9&amp;t=tpclicked3_hc&amp;td=1922429&amp;tu=u1922429&amp;u=http%3A%2F%2Fwww%2Eadmin10000%2Ecom%2Fdocument%2F6065%2Ehtml&amp;urlid=0</a>" &nbsp; target="_blank" mpid="8" style="text-decoration: &nbsp; none;"&gt;&lt;span &nbsp; style="color:#0000ff;font-size:14px;width:auto;height:auto;float:none;"&gt;java&lt;/span&gt;&lt;/a&gt;&lt;/span&gt;.awt.Dimension;&nbsp; &nbsp; import java.awt.Rectangle;&nbsp; import java.awt.Robot;&nbsp; import java.awt.Toolkit;&nbsp; import java.awt.image.BufferedImage;&nbsp; import javax.imageio.ImageIO;&nbsp; import java.io.File;&nbsp; &nbsp; ...&nbsp; &nbsp; public void captureScreen(String fileName) throws &nbsp; Exception {&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;Dimension screenSize = &nbsp; Toolkit.getDefaultToolkit().getScreenSize();&nbsp; &nbsp;&nbsp;&nbsp;Rectangle screenRectangle = new &nbsp; Rectangle(screenSize);&nbsp; &nbsp;&nbsp;&nbsp;Robot robot = new Robot();&nbsp; &nbsp;&nbsp;&nbsp;BufferedImage image = &nbsp; robot.createScreenCapture(screenRectangle);&nbsp; &nbsp;&nbsp;&nbsp;ImageIO.write(image, "png", &nbsp; new File(fileName));&nbsp; &nbsp; }&nbsp; ... </td> 
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14. 列出文件和目录

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 <td> File dir = new File("directoryName");&nbsp; &nbsp;&nbsp;String[] children = dir.list();&nbsp; &nbsp;&nbsp;if (children == null) {&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;// Either dir does &nbsp; not exist or is not a directory&nbsp; &nbsp;&nbsp;} else {&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;for (int i=0; i &nbsp; &lt; children.length; i++) {&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;// &nbsp; Get filename of file or directory&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;String &nbsp; filename = children[i];&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}&nbsp; &nbsp;&nbsp;}&nbsp; &nbsp; &nbsp;&nbsp;// It is also possible to filter the list &nbsp; of returned files.&nbsp; &nbsp;&nbsp;// This example does not return any files &nbsp; that start with `.'.&nbsp; &nbsp;&nbsp;FilenameFilter filter = new &nbsp; FilenameFilter() {&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;public boolean &nbsp; accept(File dir, String name) {&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;return &nbsp; !name.startsWith(".");&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}&nbsp; &nbsp;&nbsp;};&nbsp; &nbsp;&nbsp;children = dir.list(filter);&nbsp; &nbsp; &nbsp;&nbsp;// The list of files can also be retrieved &nbsp; as File objects&nbsp; &nbsp;&nbsp;File[] files = dir.listFiles();&nbsp; &nbsp; &nbsp;&nbsp;// This filter only returns &nbsp; directories&nbsp; &nbsp;&nbsp;FileFilter fileFilter = new FileFilter() &nbsp; {&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;public boolean &nbsp; accept(File file) {&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;return &nbsp; file.isDirectory();&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}&nbsp; &nbsp;&nbsp;};&nbsp; &nbsp;&nbsp;files = dir.listFiles(fileFilter); </td> 
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15. 创建ZIP和JAR文件

16. 解析/读取XML 文件

XML文件

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 <td> &lt;?xml version="1.0"?&gt; &lt;students&gt; &nbsp;&nbsp;&nbsp;&nbsp;&lt;student&gt; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&lt;name&gt;John&lt;/name&gt; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&lt;grade&gt;B&lt;/grade&gt; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&lt;age&gt;12&lt;/age&gt; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&lt;/student&gt; &nbsp;&nbsp;&nbsp;&nbsp;&lt;student&gt; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&lt;name&gt;Mary&lt;/name&gt; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&lt;grade&gt;A&lt;/grade&gt; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&lt;age&gt;11&lt;/age&gt; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&lt;/student&gt; &nbsp;&nbsp;&nbsp;&nbsp;&lt;student&gt; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&lt;name&gt;Simon&lt;/name&gt; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&lt;grade&gt;A&lt;/grade&gt; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&lt;age&gt;18&lt;/age&gt; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&lt;/student&gt; &lt;/students&gt; </td> 
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[Java代码][Java]

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 <td> package net.viralpatel.&lt;span id="4_nwp" &nbsp; style="width: auto; height: auto; float: none;"&gt;&lt;a &nbsp; id="4_nwl" href="<a href="http://cpro.baidu.com/cpro/ui/uijs.php?adclass=0&amp;app_id=0&amp;c=news&amp;cf=1001&amp;ch=0&amp;di=128&amp;fv=20&amp;is_app=0&amp;jk=5a3764283252b2ed&amp;k=java&amp;k0=java&amp;kdi0=0&amp;luki=3&amp;mcpm=0&amp;n=10&amp;p=baidu&amp;q=06011078_cpr&amp;rb=0&amp;rs=1&amp;seller_id=1&amp;sid=edb252322864375a&amp;ssp2=1&amp;stid=9&amp;t=tpclicked3_hc&amp;td=1922429&amp;tu=u1922429&amp;u=http%3A%2F%2Fwww.admin10000.com%2Fdocument%2F6065.html&amp;urlid=0" rel="nofollow">http://cpro.baidu.com/cpro/ui/uijs.php?adclass=0&amp;app_id=0&amp;c=news&amp;cf=1001&amp;ch=0&amp;di=128&amp;fv=20&amp;is_app=0&amp;jk=5a3764283252b2ed&amp;k=java&amp;k0=java&amp;kdi0=0&amp;luki=3&amp;mcpm=0&amp;n=10&amp;p=baidu&amp;q=06011078_cpr&amp;rb=0&amp;rs=1&amp;seller_</a> <a href="http://cpro.baidu.com/cpro/ui/uijs.php?adclass=0&amp;app_id=0&amp;c=news&amp;cf=1001&amp;ch=0&amp;di=128&amp;fv=20&amp;is_app=0&amp;jk=5a3764283252b2ed&amp;k=java&amp;k0=java&amp;kdi0=0&amp;luki=3&amp;mcpm=0&amp;n=10&amp;p=baidu&amp;q=06011078_cpr&amp;rb=0&amp;rs=1&amp;seller_id=1&amp;sid=edb252322864375a&amp;ssp2=1&amp;stid=9&amp;t=tpclicked3_hc&amp;td=1922429&amp;tu=u1922429&amp;u=http%3A%2F%2Fwww.admin10000.com%2Fdocument%2F6065.html&amp;urlid=0" rel="nofollow">id=1&amp;sid=edb252322864375a&amp;ssp2=1&amp;stid=9&amp;t=tpclicked3_hc&amp;td=1922429&amp;tu=u1922429&amp;u=http%3A%2F%2Fwww%2Eadmin10000%2Ecom%2Fdocument%2F6065%2Ehtml&amp;urlid=0</a>" &nbsp; target="_blank" mpid="4" style="text-decoration: &nbsp; none;"&gt;&lt;span &nbsp; style="color:#0000ff;font-size:14px;width:auto;height:auto;float:none;"&gt;java&lt;/span&gt;&lt;/a&gt;&lt;/span&gt;.&lt;span &nbsp; id="5_nwp" style="width: auto; height: auto; float: &nbsp; none;"&gt;&lt;a id="5_nwl" href="<a href="http://cpro.baidu.com/cpro/ui/uijs.php?adclass=0&amp;app_id=0&amp;c=news&amp;cf=1001&amp;ch=0&amp;di=128&amp;fv=20&amp;is_app=0&amp;jk=5a3764283252b2ed&amp;k=xml&amp;k0=xml&amp;kdi0=0&amp;luki=1&amp;mcpm=0&amp;n=10&amp;p=baidu&amp;q=06011078_cpr&amp;rb=0&amp;rs=1&amp;seller_id=1&amp;sid=edb252322864375a&amp;ssp2=1&amp;stid=9&amp;t=tpclicked3_hc&amp;td=1922429&amp;tu=u1922429&amp;u=http%3A%2F%2Fwww.admin10000.com%2Fdocument%2F6065.html&amp;urlid=0" rel="nofollow">http://cpro.baidu.com/cpro/ui/uijs.php?adclass=0&amp;app_id=0&amp;c=news&amp;cf=1001&amp;ch=0&amp;di=128&amp;fv=20&amp;is_app=0&amp;jk=5a3764283252b2ed&amp;k=xml&amp;k0=xml&amp;kdi0=0&amp;luki=1&amp;mcpm=0&amp;n=10&amp;p=baidu&amp;q=06011078_cpr&amp;rb=0&amp;rs=1&amp;seller_</a> <a href="http://cpro.baidu.com/cpro/ui/uijs.php?adclass=0&amp;app_id=0&amp;c=news&amp;cf=1001&amp;ch=0&amp;di=128&amp;fv=20&amp;is_app=0&amp;jk=5a3764283252b2ed&amp;k=xml&amp;k0=xml&amp;kdi0=0&amp;luki=1&amp;mcpm=0&amp;n=10&amp;p=baidu&amp;q=06011078_cpr&amp;rb=0&amp;rs=1&amp;seller_id=1&amp;sid=edb252322864375a&amp;ssp2=1&amp;stid=9&amp;t=tpclicked3_hc&amp;td=1922429&amp;tu=u1922429&amp;u=http%3A%2F%2Fwww.admin10000.com%2Fdocument%2F6065.html&amp;urlid=0" rel="nofollow">id=1&amp;sid=edb252322864375a&amp;ssp2=1&amp;stid=9&amp;t=tpclicked3_hc&amp;td=1922429&amp;tu=u1922429&amp;u=http%3A%2F%2Fwww%2Eadmin10000%2Ecom%2Fdocument%2F6065%2Ehtml&amp;urlid=0</a>" &nbsp; target="_blank" mpid="5" style="text-decoration: &nbsp; none;"&gt;&lt;span &nbsp; style="color:#0000ff;font-size:14px;width:auto;height:auto;float:none;"&gt;xml&lt;/span&gt;&lt;/a&gt;&lt;/span&gt;parser;&nbsp; &nbsp; &nbsp; import java.io.File;&nbsp; import javax.xml.parsers.DocumentBuilder;&nbsp; import javax.xml.parsers.DocumentBuilderFactory;&nbsp; &nbsp; import org.w3c.dom.Document;&nbsp; import org.w3c.dom.Element;&nbsp; import org.w3c.dom.Node;&nbsp; import org.w3c.dom.NodeList;&nbsp; &nbsp; public class XMLParser {&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;public void &nbsp; getAllUserNames(String fileName) {&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;try &nbsp; {&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;DocumentBuilderFactory &nbsp; dbf = DocumentBuilderFactory.newInstance();&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;DocumentBuilder &nbsp; db = dbf.newDocumentBuilder();&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;File &nbsp; file = new File(fileName);&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;if &nbsp; (file.exists()) {&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Document &nbsp; doc = db.parse(file);&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Element &nbsp; docEle = doc.getDocumentElement();&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;// &nbsp; Print root element of the document&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;System.out.println("Root &nbsp; element of the document: " &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;+ &nbsp; docEle.getNodeName());&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;NodeList &nbsp; studentList = docEle.getElementsByTagName("student");&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;// &nbsp; Print total student elements in document&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;System.out&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;.println("Total &nbsp; students: " + studentList.getLength());&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;if &nbsp; (studentList != null &amp;&amp; studentList.getLength() &gt; 0) {&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;for &nbsp; (int i = 0; i &lt; studentList.getLength(); i++) {&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Node &nbsp; node = studentList.item(i);&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;if &nbsp; (node.getNodeType() == Node.ELEMENT_NODE) {&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;System.out&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;.println("=====================");&nbsp; &nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Element &nbsp; e = (Element) node;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;NodeList &nbsp; nodeList = e.getElementsByTagName("name");&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;System.out.println("Name: &nbsp; " &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;+ &nbsp; nodeList.item(0).getChildNodes().item(0)&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;.getNodeValue());&nbsp; &nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;nodeList &nbsp; = e.getElementsByTagName("grade");&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;System.out.println("Grade: &nbsp; " &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;+ &nbsp; nodeList.item(0).getChildNodes().item(0)&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;.getNodeValue());&nbsp; &nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;nodeList &nbsp; = e.getElementsByTagName("age");&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;System.out.println("Age: &nbsp; " &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;+ &nbsp; nodeList.item(0).getChildNodes().item(0)&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;.getNodeValue());&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;} &nbsp; else {&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;System.exit(1);&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;} catch &nbsp; (Exception e) {&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;System.out.println(e);&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;}&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;public static void &nbsp; main(String[] args) {&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;XMLParser &nbsp; parser = new XMLParser();&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;parser.getAllUserNames("c:\\test.&lt;span &nbsp; id="6_nwp" style="width: auto; height: auto; float: &nbsp; none;"&gt;&lt;a id="6_nwl" &nbsp; href="http://cpro.baidu.com/cpro/ui/uijs.php?adclass=0&amp;app_id=0&amp;c=news&amp;cf=1001&amp;ch=0&amp;di=128&amp;fv=20&amp;is_app=0&amp;jk=5a3764283252b2ed&amp;k=xml&amp;k0=xml&amp;kdi0=0&amp;luki=1&amp;mcpm=0&amp;n=10&amp;p=baidu&amp;q=06011078_cpr&amp;rb=0&amp;rs=1&amp;seller_id=1&amp;s id=edb252322864375a&amp;ssp2=1&amp;stid=9&amp;t=tpclicked3_hc&amp;td=1922429&amp;tu=u1922429&amp;u=http%3A%2F%2Fwww%2Eadmin10000%2Ecom%2Fdocument%2F6065%2Ehtml&amp;urlid=0" &nbsp; target="_blank" mpid="6" style="text-decoration: &nbsp; none;"&gt;&lt;span &nbsp; style="color:#0000ff;font-size: 14px;width:auto;height:auto;float:none;"&gt;xml&lt;/span&gt;&lt;/a&gt;&lt;/span&gt;");&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;}&nbsp; } </td> 
 </tr> 
 </tbody> 
</table>

17. 把 Array 转换成 Map

<table> 
 <tbody> 
 <tr> 
 <td> 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 </td> 
 <td> import &lt;span id="3_nwp" style="width: &nbsp; auto; height: auto; float: none;"&gt;&lt;a id="3_nwl" &nbsp; href="<a href="http://cpro.baidu.com/cpro/ui/uijs.php?adclass=0&amp;app_id=0&amp;c=news&amp;cf=1001&amp;ch=0&amp;di=128&amp;fv=20&amp;is_app=0&amp;jk=5a3764283252b2ed&amp;k=java&amp;k0=java&amp;kdi0=0&amp;luki=3&amp;mcpm=0&amp;n=10&amp;p=baidu&amp;q=06011078_cpr&amp;rb=0&amp;rs=1&amp;seller_id=1&amp;sid=edb252322864375a&amp;ssp2=1&amp;stid=9&amp;t=tpclicked3_hc&amp;td=1922429&amp;tu=u1922429&amp;u=http%3A%2F%2Fwww.admin10000.com%2Fdocument%2F6065.html&amp;urlid=0" rel="nofollow">http://cpro.baidu.com/cpro/ui/uijs.php?adclass=0&amp;app_id=0&amp;c=news&amp;cf=1001&amp;ch=0&amp;di=128&amp;fv=20&amp;is_app=0&amp;jk=5a3764283252b2ed&amp;k=java&amp;k0=java&amp;kdi0=0&amp;luki=3&amp;mcpm=0&amp;n=10&amp;p=baidu&amp;q=06011078_cpr&amp;rb=0&amp;rs=1&amp;seller</a> <a href="http://cpro.baidu.com/cpro/ui/uijs.php?adclass=0&amp;app_id=0&amp;c=news&amp;cf=1001&amp;ch=0&amp;di=128&amp;fv=20&amp;is_app=0&amp;jk=5a3764283252b2ed&amp;k=java&amp;k0=java&amp;kdi0=0&amp;luki=3&amp;mcpm=0&amp;n=10&amp;p=baidu&amp;q=06011078_cpr&amp;rb=0&amp;rs=1&amp;seller_id=1&amp;sid=edb252322864375a&amp;ssp2=1&amp;stid=9&amp;t=tpclicked3_hc&amp;td=1922429&amp;tu=u1922429&amp;u=http%3A%2F%2Fwww.admin10000.com%2Fdocument%2F6065.html&amp;urlid=0" rel="nofollow">_i</a><a href="http://cpro.baidu.com/cpro/ui/uijs.php?adclass=0&amp;app_id=0&amp;c=news&amp;cf=1001&amp;ch=0&amp;di=128&amp;fv=20&amp;is_app=0&amp;jk=5a3764283252b2ed&amp;k=java&amp;k0=java&amp;kdi0=0&amp;luki=3&amp;mcpm=0&amp;n=10&amp;p=baidu&amp;q=06011078_cpr&amp;rb=0&amp;rs=1&amp;seller_id=1&amp;sid=edb252322864375a&amp;ssp2=1&amp;stid=9&amp;t=tpclicked3_hc&amp;td=1922429&amp;tu=u1922429&amp;u=http%3A%2F%2Fwww.admin10000.com%2Fdocument%2F6065.html&amp;urlid=0" rel="nofollow">d=1&amp;sid=edb252322864375a&amp;ssp2=1&amp;stid=9&amp;t=tpclicked3_hc&amp;td=1922429&amp;tu=u1922429&amp;u=http%3A%2F%2Fwww%2Eadmin10000%2Ecom%2Fdocument%2F6065%2Ehtml&amp;urlid=0</a>" &nbsp; target="_blank" mpid="3" style="text-decoration: &nbsp; none;"&gt;&lt;span &nbsp; style="color:#0000ff;font-size:14px;width:auto;height:auto;float:none;"&gt;java&lt;/span&gt;&lt;/a&gt;&lt;/span&gt;.util.Map;&nbsp;&nbsp;&nbsp; import org.apache.commons.lang.ArrayUtils;&nbsp; &nbsp; public class Main &nbsp; {&nbsp; &nbsp; &nbsp;&nbsp;public static void main(String[] args) &nbsp; {&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;String[][] countries = { { &nbsp; "United States", &nbsp; "New York" }, { "United Kingdom", "London" },&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;{ &nbsp; "Netherland", "Amsterdam" &nbsp; }, { "Japan", &nbsp; "Tokyo" &nbsp; }, { "France", "Paris" } };&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;Map countryCapitals = &nbsp; ArrayUtils.toMap(countries);&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;System.out.println("Capital &nbsp; of Japan is " + countryCapitals.get("Japan"));&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;System.out.println("Capital &nbsp; of France is " + countryCapitals.get("France"));&nbsp; &nbsp;&nbsp;}&nbsp; } </td> 
 </tr> 
 </tbody> 
</table>

18. 发送邮件

19. 发送代数据的HTTP 请求

<table> 
 <tbody> 
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 <td> 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 </td> 
 <td> import &lt;span id="1_nwp" style="width: &nbsp; auto; height: auto; float: none;"&gt;&lt;a id="1_nwl" &nbsp; href="<a href="http://cpro.baidu.com/cpro/ui/uijs.php?adclass=0&amp;app_id=0&amp;c=news&amp;cf=1001&amp;ch=0&amp;di=128&amp;fv=20&amp;is_app=0&amp;jk=5a3764283252b2ed&amp;k=java&amp;k0=java&amp;kdi0=0&amp;luki=3&amp;mcpm=0&amp;n=10&amp;p=baidu&amp;q=06011078_cpr&amp;rb=0&amp;rs=1&amp;seller_id=1&amp;sid=edb252322864375a&amp;ssp2=1&amp;stid=9&amp;t=tpclicked3_hc&amp;td=1922429&amp;tu=u1922429&amp;u=http%3A%2F%2Fwww.admin10000.com%2Fdocument%2F6065.html&amp;urlid=0" rel="nofollow">http://cpro.baidu.com/cpro/ui/uijs.php?adclass=0&amp;app_id=0&amp;c=news&amp;cf=1001&amp;ch=0&amp;di=128&amp;fv=20&amp;is_app=0&amp;jk=5a3764283252b2ed&amp;k=java&amp;k0=java&amp;kdi0=0&amp;luki=3&amp;mcpm=0&amp;n=10&amp;p=baidu&amp;q=06011078_cpr&amp;rb=0&amp;rs=1&amp;seller_</a> <a href="http://cpro.baidu.com/cpro/ui/uijs.php?adclass=0&amp;app_id=0&amp;c=news&amp;cf=1001&amp;ch=0&amp;di=128&amp;fv=20&amp;is_app=0&amp;jk=5a3764283252b2ed&amp;k=java&amp;k0=java&amp;kdi0=0&amp;luki=3&amp;mcpm=0&amp;n=10&amp;p=baidu&amp;q=06011078_cpr&amp;rb=0&amp;rs=1&amp;seller_id=1&amp;sid=edb252322864375a&amp;ssp2=1&amp;stid=9&amp;t=tpclicked3_hc&amp;td=1922429&amp;tu=u1922429&amp;u=http%3A%2F%2Fwww.admin10000.com%2Fdocument%2F6065.html&amp;urlid=0" rel="nofollow">id=1&amp;sid=edb252322864375a&amp;ssp2=1&amp;stid=9&amp;t=tpclicked3_hc&amp;td=1922429&amp;tu=u1922429&amp;u=http%3A%2F%2Fwww%2Eadmin10000%2Ecom%2Fdocument%2F6065%2Ehtml&amp;urlid=0</a>" &nbsp; target="_blank" mpid="1" style="text-decoration: &nbsp; none;"&gt;&lt;span style="color:#0000ff;font-size:14px;width:auto;height:auto;float:none;"&gt;java&lt;/span&gt;&lt;/a&gt;&lt;/span&gt;.io.BufferedReader;&nbsp; &nbsp; import java.io.InputStreamReader;&nbsp; import java.net.URL;&nbsp; &nbsp; public class Main &nbsp; {&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;public static void &nbsp; main(String[] args)&nbsp; {&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;try &nbsp; {&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;URL &nbsp; my_url = new URL("http://coolshell.cn/");&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;BufferedReader &nbsp; br = new BufferedReader(new InputStreamReader(my_url.openStream()));&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;String &nbsp; strTemp = "";&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;while(null &nbsp; != (strTemp = br.readLine())){&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;System.out.println(strTemp);&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;} catch &nbsp; (Exception ex) {&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ex.printStackTrace();&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}&nbsp; &nbsp; &nbsp;&nbsp;&nbsp;&nbsp;}&nbsp; } </td> 
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 </tbody> 
</table>

20. 改变数组的大小

[Java]: http://www.bjsxt.com