考题
在J2EE中,假如在当前目录下不存在employee.txt文件。在当前目录下的一个类文件的main函数只包含如下代码:try{//1PrintWriterout=newPrintWriter(newFileOutputStream(employee.txt”));//2Stringname=jb-aptech”;//3doublesalary=75000;//4out.print(name);//5out.print(‘‘);//6out.println(salary);//7}//8catch(Exceptione)//9System.out.println(文件没有发现!);//10在DOS控制台上编译并且运行该类文件。下面的描述正确的是()。A.使用java命令运行该类文件,将在控制台上打印:文件没有发现!B.运行结束后打开employee.txt,会发现该文件什么也没有C.运行结束后打开employee.txt,会发现文件中有这样的文本:“jb-aptech75000”D.在第7行后加上代码:out.close(),编译并运行该类文件后,打开employee.txt,才会发现文件中有这样的文本:“jb-aptech75000.0”E.把第2行代码改为:PrintWriterout=newPrintWriter(newFileOutputStream(“employee.txt”),true);编译并运行该类文件后,打开employee.txt,才会发现文件中有这样的文本:“jb-aptech75000.0”
考题
在J2EE中,加入在当前目录下不存在employee.txt文件。在当前目录下的一个类文件的main函数只包含如下代码:try{//1PrintWriterout=newPrintWriter(newFileOutputStream(employee.txt”));//2Stringname=”jb-aptech”;//3doublesalary=75000;//4out.print(name);//5out.print(??);//6out,print(salary);//7}//8catch(Exceptione){//9System.out.println(文件没有被发现!”);//10}//11在DOS控制台上编译并运行该类文件。下面描述正确的是()。
考题
本题的功能是将文件java2.java复制为文件java2.java.bak。 importjava.io.*; public class java2{ public static void main(String sarg[]){ try{File file=new File("java2.java.bak"); ; FilelnputStream rfile=new FilelnputStream("ja- va2.java"); FileOutputStream wfile=new FileOutputStream ("java2.java.bak"); int c; while( ) wfile.write((char)c); rfile.close; wfile.close; }catch(Exception e){System.out.println("读取文 件的时候发生错误!");} System.out.println("复制操作完成!"); } }
考题
请完成程序,首先由一个类simple实现Serializable接口,并有三个成员变量,分别为int型、double型和String型,可以用toString的方法显示这三个成员变量。在main方法中创建这个simple的持久对象,根据用户在命令行输入的三个参数来设定其中成员变量的值。然后,将这个对象写入名为TheSerial.data的文件中,并显示成员变量。最后从文件TheSerial.data中读出三个成员变量并显示出来。注意:请勿修改main()主方法和其他已有语句内容,仅在横线处填入适当语句。import java.io.*;class TheSerial implements Serializable{private int intvalue;private double doublevalue;private String string;The Serial (){intvalue=123;doublevalue=12.34;string="Serialize Test";}public void setDouble(double d){doublevalue=d;}public void setInt(int i){intvalue=i;}public void setString(String s){string=s;}public String to String(){return("int="+intvalue+" double="+doublevalue+" string="+string);}}public class simple{public static void main(String[] args){The Serial e1=new TheSerial();TheSerial e2;try{e1.setInt(Integer.parseInt(args[0]));e1.setDouble(Double.parseDouble(args[1]));e1.setString(args[2]);}catch(Exception e){e1.setString(e.getMessage());}System.out.println(e1);try{FileOutputStream S=new FileOutputStream("TheSerial.data");ObjectOutputStream OS=new ObjectOutputStream(oS);______;}catch(IOException ioException){System.out.println (ioException.getMessage ());}try{FileInputStream iS=new FileInputStream("TheSerial.data");ObjectInputStream IS=new ObjectInputStream(iS);______;System.out.println(e2);}catch(IOException ioException){System.out.println(ioException.getMessage());}catch(ClassNotFoundException cnfException){System.out.println(cnfException.getMessage());}}}
考题
阅读以下说明和Java代码,将应填入(n)处的字句写在对应栏内。[说明]本程序的功能是给公司的员工Tom,Jack,Green增加薪水。三人的职位分别是programmer, Manager,CEO。程序由6个类组成:WorkerTest是主类,programmer,Manager,CEO三个类,薪水增加的规则是 programmer的涨幅是5%;Manager的是10%;CEO也是Manager,但是它除了有Manager的涨幅,还有1000元的bonus。接口SalaryRaise提供了一个增加薪水的方法raise()。[java程序]public class WorkerTest {public WorkerTest( ) {}public static void main( String[] args) {Programmer programmer = new Programmer( "Tom" ,3000);Manager manager = new Manager( "Jack" ,4000);CEO ceo = new CEO( "Green" ,4000);Worker [] worker = new Worker[3];programmer, raise( );manager, raise( );ceo. raise( );worker[0] = programmer;worker [1] = manager;worker[2] = ceo;for ( int i = 0 ;i < worker, length; i + + ) {System. out. prinfln (" Name:" + worker [i]. getName ( ) +" \ tSalary:" + worker [i]. getSalary ());public interface SalaryRaise { void raise( ); }public class Worker {public String name;public double (1);public Worker( ) {}public String getName( ) {return name;}public void setName( String name) {this. name = name;}public double getSalary( ) {return salary;}public void setSalary(double salary) { this. salary = salary; }}public class Programmer extends Worker implements (2) {public Programmer( ) {}public void raise( ) {double pets=0.05;double sala = this. getSalary( ) * (1 + pers);this. setSalary (sala);public Programmer( Siring name, double salary) tthis. name = name;this. salary = salary;public class Manager extends (3) implements SalaryRaise {public Manager( ) { }public Manager(String name, double salary) {this. name = name;this. salary = salary;}public void raise( ) {double pets = 0.1;double sala = this. getSalary() * (1 + pers);this. setSalary(sala);}}public class CEO extends Manager implements SalaryRaise {public CEO() {}public CEO( String name,double salary) {this. name = name;this. salary = salary;}public void raise( ) {double bonus = 1000;(4);double sala = this. getSalary( );(5);this. setSalary(sala);}}
考题
请完成以下程序,首先由一个类Example2_3实现Serializable接口,并有三个成员变量,分别为int型、double型和String型,可以用toString的方法显示这三个成员变量。在main方法中创建这个Example2_3的持久对象,根据用户在命令行输入的三个参数来设定其中成员变量的值。然后,将这个对象写入名为TheSerial.data的文件,并显示成员变量。最后从文件TheSerial.data中读出三个成员变量并显示出来。注意:请勿改动main()主方法和其他已有语句内容,仅在横线处填入适当语句。import java.io.*;class TheSerial implements Serializable{private int intValue;private double doubleValue;private String string;TheSerial(){intValue = 123;doubleValue = 12.34;string = "Serialize Test";}public void setDouble(double d){doubleValue = d;}public void setInt(int i){intValue = i;}public void setString(String s){string = s;}public String toString(){return("int="+intValue+"double="+doubleValue+" string="+string);}}public class Example2_3{public static void main(String argv[]){TheSerial e1 = new TheSerial();TheSerial e2;try{e1.setInt(Integer.parseInt(argv[0]));e1.setDouble(Double.parseDouble(argv[1]));e1.setString[argv[2]);}catch(Exception e){e1.setString(e.getMessage{));}System.out.println(e1);try{FileOutputStream S = new FileOutputStream("TheSerial.data");ObjectOutputStream IS = new ObjectOutputStream(oS);______;}catch(IOException ioException){System.out.println(ioException.getMessage());}try{FileInputStream iS = new FileInputStream("TheSerial. data");ObjectInputStream IS = new ObjectInputStream(iS);______System.out.println(e2);}catch(IOException ioException){System.out.println(ioException.getMessage());}catch(ClassNotFoundException cnfException){System.out.println(cnfException.getMessage());}}}
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下列程序执行后的结果是______。 package ch1; import java.io.*; public class ex22 { static, String filename = "ch1\kfile22.txt"; public static void main(String[] args) { try { FileWriter fr = new FileWriter(filename); PrintWriter pr = new PrintWriter(fr); String name = "xiaoming"; String phone = "123456"; String age = "12"; pr.println(name + ',' + phone + ',' + age); pr.close(); fr.close(); } catch(IOException ioe) { ioe.printStackTrace() } } }A.在包ch1 中新建一个文件file22.txt, 并且在其中写入一行字符串“xiaomingl2345612”B.在包ch1中新建一个文件file22.txt,并且在其中写入一行字符串“xiaoming, 123456,12”C.在包chi中新建一个文件file22.txt,并且在其中写入一行字符串“xiaoming'’D.抛出IOException
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下列程序的运行结果是______。 package ch1; import java.io. *; public class ex28 { public static void main (String args [] ) throws IOException { try { File f1 = new File("ch1\\dir28"); f1.mkdir(); File f2 = new File(f1, "file59.txt"); FileOutputStream fos = new FileOutputStream(f2); for(int i = 0; i < 2; i++) { String s= i + "times"; byte[] b = s.getBytes(); fos.write(b,0,b.length); } } catch(IOException ioe) { ioe.printStackTrace(); } } }A.在目录ch1下建立一个目录dir28,并且建立文件file28.txt,在文件中写入"Otimes 1 times"B.在目录ch1下建立一个目录dir28,并且建立文件file28.txt,在文件中写入“l times”C.在目录chi下建立一个目录dir28,并且建立文件file28.txt,在文件中写入“Otimes”D.抛出IOExceptin异常
考题
在J2EE中,加入在当前目录下不存在employee.txt文件。在当前目录下的一个类文件的 main函数只包含如下代码: try{ //1 PrintWriter out=new PrintWriter(new FileOutputStream(“employee.txt”));//2 String name=”jb-aptech”; //3 double salary=75000; //4 out.print(name); //5 out.print(„ „); //6 out,print(salary); //7 } //8 catch(Exception e) { //9 System.out.println(“文件没有被发现!”); //10 } //11 在DOS控制台上编译并运行该类文件。下面描述正确的是()。 A、使用java命令运行该类文件,将在控制台上打印:”文件没有发现!”;B、运行结束后打开employee.txt,会发现该文件什么都没有C、运行结束后打开employee.txt,会发现该文件中有这样的文本:”jb-aptech 75000”D、在第7行后加上代码:out.close (),编译并运行后,打开打开employee.txt,才会发现该文件中有这样的文本:”jb-aptech 75000.0”
考题
在J2EE中,假如在当前目录下不存在employee.txt文件。在当前目录下的一个类文件的main函数只包含如下代码: try { PrintWriter out = new PrintWriter(new FileOutputStream(“employee.txt”)); String name = “jb-aptech”; double salary = 75000; out.print(name); out.print(„ „); out.println(salary); } catch(Exception e) System.out.println("文件没有发现!"); 在DOS控制台上编译并且运行该类文件。下面的描述正确的是()。 A、使用java命令运行该类文件,将在控制台上打印:"文件没有发现!"B、运行结束后打开employee.txt,会发现该文件什么也没有C、运行结束后打开employee.txt,会发现文件中有这样的文本:“jb-aptech 75000”D、在第7行后加上代码:out.close(),编译并运行该类文件后,打开employee.txt,才会发现文件中有这样的文本:“jb-aptech 75000.0”E、把第2行代码改为: PrintWriter out = new PrintWriter(new FileOutputStream(“employee.txt”),true); 编译并运行该类文件后,打开employee.txt,才会发现文件中有这样的文本:“jb-aptech 75000.0”
考题
在J2EE中,利用下列构造函数准备对文件abc.txt操作,但文件abc.txt在当前目录不存在,不会产生运行时错误的是()。 A、BufferedReader breader=new BufferedReader(new FileReader("abc.txt"));B、PrintWriter out = new PrintWriter(new FileWriter(“abc.txt”),true);C、FileInputStream fin = new FileInputStream(“abc.txt”);D、OutputStreamWriter out = new OutputStreamWriter(new FileOutputStream(“abc.txt”));
考题
在J2EE中,Servlet1的代码如下: import javax.servlet.*; import javax.servlet.http.*; import java.io.*; public class Servlet1 extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType("text/html"); PrintWriter out = response.getWriter(); String aa=request.getQueryString(); String bb=request.getMethod(); out.println(aa); out.println(bb); } } 把Servlet1.class文件放在Web服务器适合的目录下,在浏览B器地址栏内输入:http://localhost:8080/servlet/Servlet1?name=jb-aptechphone=12345678,看到的结果是()。 A、name=jb-aptechphone=12345678 GETB、name=jb-aptech,phone=12345678 GETC、jb-aptech,12345678 POSTD、name,phone GETE、2,POST
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//point X public class foo ( public static void main (String[]args) throws Exception { printWriter out = new PrintWriter (new java.io.outputStreamWriter (System.out), true; out.printIn(“Hello”); } ) Which statement at PointX on line 1 allows this code to compile and run?() A、 Import java.io.PrintWriter;B、 Include java.io.PrintWriter;C、 Import java.io.OutputStreamWriter;D、 Include java.io.OutputStreamWriter;E、 No statement is needed.
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在J2EE中,如果去编译并运行下面的代码,在这里假定在当前目录下没有Hello.txt文件: import java.io.*; public class Mine { public static void main(String argv[]){ Mine m=new Mine(); System.out.println(m.amethod()); } public int amethod() { try { FileInputStream dis=new FileInputStream("Hello.txt"); } catch (FileNotFoundException fne) { System.out.println("No such file found"); return -1; } catch(IOException ioe) { } finally { System.out.println("Doing finally"); } return 0; } } 结果会输出()。 A、No such file foundB、No such file found -1C、No such file found doing finally -1D、0
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//point X public class foo { public static void main (String[]args) throws Exception { java.io.printWriter out = new java.io.PrintWriter { new java.io.outputStreamWriter (System.out), true; out.printIn(“Hello”); } } } Which statement at PointX on line 1 allows this code to compile and run?() A、 Import java.io.*;B、 Include java.io.*;C、 Import java.io.PrintWriter;D、 Include java.io.PrintWriter;E、 No statement is needed.
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//point X public class foo { public static void main (Stringargs) throws Exception { java.io.printWriter out = new java.io.PrintWriter { new java.io.outputStreamWriter (System.out), true; out.printIn(“Hello”); } } } Which statement at PointX on line 1 allows this code to compile and run?() A、 Import java.io.*;B、 Include java.io.*;C、 Import java.io.PrintWriter;D、 Include java.io.PrintWriter;E、 No statement is needed.
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class Waiting implements Runnable { boolean flag = false; public synchronized void run() { if (flag) { flag = false; System.out.print("1 "); try { this.wait(); } catch (Exception e) { } System.out.print("2 "); } else { flag = true; System.out.print("3 "); try { Thread.sleep(2000); } catch (Exception e) { } System.out.print("4 "); notify(); } } public static void main(String [] args) { Waiting w = new Waiting(); new Thread(w).start(); new Thread(w).start (); } } 以下哪两项是正确的?() A、代码输出 1 3 4B、代码输出 3 4 1C、代码输出 1 2 3 4D、代码不会完成
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//point X public class foo ( public static void main (Stringargs) throws Exception { printWriter out = new PrintWriter (new ) java.io.outputStreamWriter (System.out), true; out.printIn(“Hello”); } ) Which statement at PointX on line 1 allows this code to compile and run?()A、 Import java.io.PrintWriter;B、 Include java.io.PrintWriter;C、 Import java.io.OutputStreamWriter;D、 Include java.io.OutputStreamWriter;E、 No statement is needed.
考题
多选题在J2EE中,利用下列构造函数准备对文件abc.txt操作,但文件abc.txt在当前目录不存在,不会产生运行时错误的是()。ABufferedReader breader=new BufferedReader(new FileReader(abc.txt));BPrintWriter out = new PrintWriter(new FileWriter(“abc.txt”),true);CFileInputStream fin = new FileInputStream(“abc.txt”);DOutputStreamWriter out = new OutputStreamWriter(new FileOutputStream(“abc.txt”));
考题
多选题在J2EE中,加入在当前目录下不存在employee.txt文件。在当前目录下的一个类文件的 main函数只包含如下代码: try{ //1 PrintWriter out=new PrintWriter(new FileOutputStream(“employee.txt”));//2 String name=”jb-aptech”; //3 double salary=75000; //4 out.print(name); //5 out.print(„ „); //6 out,print(salary); //7 } //8 catch(Exception e) { //9 System.out.println(“文件没有被发现!”); //10 } //11 在DOS控制台上编译并运行该类文件。下面描述正确的是()。A使用java命令运行该类文件,将在控制台上打印:”文件没有发现!”;B运行结束后打开employee.txt,会发现该文件什么都没有C运行结束后打开employee.txt,会发现该文件中有这样的文本:”jb-aptech 75000”D在第7行后加上代码:out.close (),编译并运行后,打开打开employee.txt,才会发现该文件中有这样的文本:”jb-aptech 75000.0”
考题
多选题在J2EE中,假如在当前目录下不存在employee.txt文件。在当前目录下的一个类文件的main函数只包含如下代码: try { PrintWriter out = new PrintWriter(new FileOutputStream(“employee.txt”)); String name = “jb-aptech”; double salary = 75000; out.print(name); out.print(„ „); out.println(salary); } catch(Exception e) System.out.println("文件没有发现!"); 在DOS控制台上编译并且运行该类文件。下面的描述正确的是()。A使用java命令运行该类文件,将在控制台上打印:文件没有发现!B运行结束后打开employee.txt,会发现该文件什么也没有C运行结束后打开employee.txt,会发现文件中有这样的文本:“jb-aptech 75000”D在第7行后加上代码:out.close(),编译并运行该类文件后,打开employee.txt,才会发现文件中有这样的文本:“jb-aptech 75000.0”E把第2行代码改为: PrintWriter out = new PrintWriter(new FileOutputStream(“employee.txt”),true); 编译并运行该类文件后,打开employee.txt,才会发现文件中有这样的文本:“jb-aptech 75000.0”
考题
单选题在J2EE中,Servlet1的代码如下: import javax.servlet.*; import javax.servlet.http.*; import java.io.*; public class Servlet1 extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType("text/html"); PrintWriter out = response.getWriter(); String aa=request.getQueryString(); String bb=request.getMethod(); out.println(aa); out.println(bb); } } 把Servlet1.class文件放在Web服务器适合的目录下,在浏览B器地址栏内输入:http://localhost:8080/servlet/Servlet1?name=jb-aptechphone=12345678,看到的结果是()。A
name=jb-aptechphone=12345678 GETB
name=jb-aptech,phone=12345678 GETC
jb-aptech,12345678 POSTD
name,phone GETE
2,POST
考题
多选题在J2EE中,假如在当前目录下不存在employee.txt文件。在当前目录下的一个类文 件的main函数只包含如下代码: try{ //1 PrintWriter out =new PrintWriter(new FileOutputStream(“employee.txt”)); //2 String name = “jb-aptech”; //3 double salary = 75000; //4 out.print(name); //5 out.print(“ ”); //6 out.println(salary); //7 } //8 catch(Exception e) { //9 System.out.println(“文件没有发现!”); //10 } //11 在DOS控制台上编译并且运行该类文件。下面的描述正确的是()。A使用java命令运行该类文件,将在控制台上打印:”文件没有发现!”B运行结束后打开employee.txt,会发现该类文件什么也没有C运行结束打开employee.txt,会发现文件中有这样的文本:“jb-aptech 75000”D在第7行后加上:out.close(),编译并运行该文件后,打开employee.txt,会发现文件中有这样的文本:“jb-aptech 75000.0”E把第2行代码改为:PrintWriter out = PrintWriter(new File
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单选题//point X public class foo { public static void main (Stringargs) throws Exception { java.io.printWriter out = new java.io.PrintWriter { new java.io.outputStreamWriter (System.out), true; out.printIn(“Hello”); } } } Which statement at PointX on line 1 allows this code to compile and run?()A
Import java.io.*;B
Include java.io.*;C
Import java.io.PrintWriter;D
Include java.io.PrintWriter;E
No statement is needed.
考题
单选题//point X public class foo { public static void main (String[]args) throws Exception { java.io.printWriter out = new java.io.PrintWriter { new java.io.outputStreamWriter (System.out), true; out.printIn(“Hello”); } } } Which statement at PointX on line 1 allows this code to compile and run?()A
Import java.io.*;B
Include java.io.*;C
Import java.io.PrintWriter;D
Include java.io.PrintWriter;E
No statement is needed.
考题
多选题在J2EE中,假如在当前目录下不存在employee.txt文件。在当前目录下的一个类文件的main函数只包含如下代码: try{//1 PrintWriterout=newPrintWriter(newFileOutputStream(“employee.txt”));//2 Stringname=“jb-aptech”;//3 doublesalary=75000;//4 out.print(name);//5 out.print(‘‘);//6 out.println(salary);//7 }//8 catch(Exceptione)//9 System.out.println("文件没有发现!");//10 在DOS控制台上编译并且运行该类文件。下面的描述正确的是()。A使用java命令运行该类文件,将在控制台上打印:文件没有发现!B运行结束后打开employee.txt,会发现该文件什么也没有C运行结束后打开employee.txt,会发现文件中有这样的文本:“jb-aptech75000”D在第7行后加上代码:out.close(),编译并运行该类文件后,打开employee.txt,才会发现文件中有这样的文本:“jb-aptech75000.0”E把第2行代码改为:PrintWriterout=newPrintWriter(newFileOutputStream(“employee.txt”),true);编译并运行该类文件后,打开employee.txt,才会发现文件中有这样的文本:“jb-aptech75000.0”
考题
单选题在J2EE中,如果去编译并运行下面的代码,在这里假定在当前目录下没有Hello.txt文件: import java.io.*; public class Mine { public static void main(String argv[]){ Mine m=new Mine(); System.out.println(m.amethod()); } public int amethod() { try { FileInputStream dis=new FileInputStream("Hello.txt"); } catch (FileNotFoundException fne) { System.out.println("No such file found"); return -1; } catch(IOException ioe) { } finally { System.out.println("Doing finally"); } return 0; } } 结果会输出()。A
No such file foundB
No such file found -1C
No such file found doing finally -1D
0