class cricket{
void bat(){
System.out.println("sachin");
}
public static void main(String ar[]){
cricket cricket=new cricket();
cricket.bat();
}
}
输出:萨钦
对象名称与类名相同.如何可能..程序正在给出正确的output.wt是什么原因？
我正在阅读有关Pass by Value和Pass的参考资料,我得到了很多文章,其中一些人说Java只遵循'按值传递',其中一些说原始和对象之间存在一些差异.所以我写了下面的示例代码并且还要输出.请评论和分享答案是什么.
我检查了Int,String,StringBuffer和Employee类,现在它仅作为Employee类的引用传递.
package test;
class Emp {
public String name="";
public int age=0;
public Emp(String name, int age) {
super();
this.name = name;
this.age = age;
}
public String toString() {
return "Name: "+ this.name + "....Age: "+ this.age;
}
}
public class Class1 {
public Class1() {
super();
}
public void doChange(int i) {
i = i +10;
System.out.println("Value of Integer in Method:>"+ i);
}
public void doChange(Emp i) {
i.age=29;
i.name="rishu";
System.out.println("Value of Employee In Method …首先看下面的代码
public static void main(String args[])
{
System.out.println(new Stringtest().test("The system has saved your payment under transaction number \369825655."));
}
private String test(String aa)
{
return aa.substring(58);
}
所以逻辑上这个方法应该打印369825665.但是由于反斜杠它打印9825655.现在我想要整数.我该怎么办.我无法将\更改为\\因为文本来自网站.
我有一个动态的对象数组,我调整了大小.调整大小后,我可以调用int和double对象的set方法,但不能调用任何带有字符串对象的setter.无论何时我尝试在调整大小的数组中为新索引调用setter,我都会获得核心转储.
这是生成错误的代码的主要部分.
void resizeAccounts(int newSize, Account *accounts, int acctNum, std::string fName, :string lName, std::string acctP, double balance)
{
Account* newArr = new Account[newSize];
for (int i=0; i<newSize-1; i++)
newArr[i]=accounts[i];
delete [] accounts;
accounts = newArr;
accounts[newSize].setAccountNum(acctNum);
accounts[newSize].setFirstName(fName);
accounts[newSize].setLastName(lName);
accounts[newSize].setAccountPassword(acctP);
accounts[newSize].setBalance(balance);
for(int i=0; i<newSize; i++)
std::cout << accounts[i].getAccountNum() << std::endl;
我正在使用的二传手
void Account::setFirstName( std::string fName)
{ firstName = fName; }
void Account::setLastName( std::string lName )
{ lastName = lName; }
void Account::setAccountPassword( std::string acctPass)
{ accountPassword = acctPass; }
void Account::setAccountNum( …为什么我们不需要编译我们在类中引用的其他类,例如,有源代码编写为
public class b
{
static
{
System.out.println("source file");
}
}
然后还有另一个源文件
class a
{
public static void main(String arr[])
{
b x=new b();
}
}
当我们编译类a时,它会自动为b生成类......？为什么会这样？
为什么我的输出等于5？我期待6,因为在"addthenumber(x);"之后 line,方法被调用,我想的是方法执行计算,5变为6.所以sysout应该打印6,但它是如何5？
public class CodeMomkeyPassingvalue
{
public static void main(String[] args)
{
int x = 5;
addthenumber(x);
System.out.println(x);
}
private static void addthenumber(int number)
{
number = number+1;
}
}
输出:
5
我的快速项目中有一个旧类"Approval.swift"
我在Core Data中添加了NSManagedObject(Approval),并为该实体创建了具有相同名称(Approval.swift)的NSManagedObject子类
然后我将实体名称更改为"ApprovalObject",并将关联的类更改为ApprovalObject.swift,以将其与旧类"Approval.swift"区分开来
当我试图运行该项目时,我收到此错误
重复符号_OBJC_METACLASS _ $ _ Card in:/Users/MyUser/Library/Developer/Xcode/DerivedData/MyProject-czluntwgoefegbeilusmojsyejlc/Build/Intermediates/MyProject.build/Debug-iphoneos/MyProject.build/Objects-normal/armv7/ApprovalObject.o/Users/MyUser/Library/Developer/Xcode/DerivedData/MyProject-czluntwgoefegbeilusmojsyejlc/Build/Intermediates/MyProject.build/Debug-iphoneos/MyProject.build/Objects-normal/armv7/Card.o重复符号_OBJC_CLASS _ $ _卡片:/ Users /MyUser/Library/Developer/Xcode/DerivedData/MyProject-czluntwgoefegbeilusmojsyejlc/Build/Intermediates/MyProject.build/Debug-iphoneos/MyProject.build/Objects-normal/armv7/ApprovalObject.o/Users/MyUser/Library/Developer/Xcode /DerivedData/MyProject-czluntwgoefegbeilusmojsyejlc/Build/Intermediates/MyProject.build/Debug-iphoneos/MyProject.build/Objects-normal/armv7/Card.o
ld:架构armv7 clang的2个重复符号:错误:链接器命令失败,退出代码为1(使用-v查看调用)
有人可以帮我解决这个错误吗？非常感谢
在下面的代码中,我发现如果我们在参数中传递map,使用putAll方法可能会导致问题
public class Main {
public static void main(String...strings ) {
Etudiant e1=new Etudiant(5, "A");
Etudiant e2=new Etudiant(6, "B");
Map<Integer, Etudiant> map= new HashMap<>();
map.put(1, e1);
map.put(2, e2);
Map<Integer, Etudiant> map2= new HashMap<>();
map2.put(1,map.get(1));
map2.put(1,map.get(2));
changeMe(map2);
System.out.println(map.get(1));
Map<Integer, Etudiant> map3= new HashMap<>();
map3.putAll(map);
changeMe(map3);
System.out.println(map.get(1));
}
private static void changeMe(Map<Integer, Etudiant> etudiants) {
etudiants.get(1).name="K";
}
}
}
这是输出结果:
Etudiant [age=5, name=A]
Etudiant [age=5, name=K]
你能解释一下这个区别吗？
为什么使用putAll之后对象会发生变化？
我如何以及在哪里可以获取mqserie aka amqmdnetstd.dll的.net核心dll？有什么好处吗？如何将消息发送到队列，当tryinh访问队列时，我在此2082上遇到错误
队列= mqManager.AccessQueue（queueName，openOptions）;
MQQueueManager queueManager = null;
MQQueue queue=null;
try
{
properties = new Hashtable();
properties.Add(MQC.TRANSPORT_PROPERTY, MQC.TRANSPORT_MQSERIES_MANAGED);
properties.Add(MQC.HOST_NAME_PROPERTY, queueManagerName);
properties.Add(MQC.PORT_PROPERTY, 1414);
properties.Add(MQC.CHANNEL_PROPERTY, MQChannel);
properties.Add(MQC.USER_ID_PROPERTY, connectionName);
properties.Add(MQC.PASSWORD_PROPERTY, "");
queueManager = new MQQueueManager("MNTSCM01", properties);
quqeue=queueManager .AccessQueue(queueName, openOptions);
}
catch (MQException mqex)
{
// Console out exception
}
我有以下课程：
public class AssignmentDetails : EntityBase
{
public DateTime StartingTime { get; protected set; }
public DateTime EndingTime { get; protected set; }
public ICollection<AssignedUser> AssignedUsers { get; protected set;}
public Assignment Assigment { get; protected set; }
public int AssigmentId { get; protected set; }
public int OwnerId { get; protected set; }
public User Owner { get; protected set; }
public State State { get; protected set; }
public AssignmentDetails(DateTime startingTime,DateTime endingTime,int ownerId,State state,ICollection<AssignedUser> assignedUsers)
{
AssignedUsers = …