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JPA or JDBC, how are they different?
I am learning Java EE and I downloaded the eclipse with glassfish for the same. I saw some examples and also read the Oracle docs to know all about Java EE 5. Connecting to a database was very simple. I opened a dynamic web project, created a session EJB , I used EntityManager and with the get meth...
How to get the first non-null value in Java?
Is there a Java equivalent of SQL's COALESCE function? That is, is there any way to return the first non-null value of several variables?
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What is float in Java?
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In Java, when you type a decimal number as 3.6, its interpreted as a double. double is a 64-bit precision IEEE 754 floating point, while floatis a 32-bit precision IEEE 754 floating point. As a float is less precise than a doub...
DaffyMenu 扩展：弹出菜单扩展，为组件添加弹出式菜单功能 · App Inventor 2 中文网
...按钮 "用户管理"
调用 DaffyMenu1.添加菜单项 管理按钮 "系统设置"
调用 DaffyMenu1.添加菜单项 管理按钮 "数据备份"
否则如果 用户权限 = "用户" 则
// 普通用户菜单
调用 DaffyMenu1.清除菜单项 用户按钮
调用 DaffyMenu1.添...
How do I run IDEA IntelliJ on Mac OS X with JDK 7?
...) make sure you have LANG=en_US.UTF-8 in your environment, see the related Java issues:
http://java.net/jira/browse/MACOSX_PORT-165
http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=7187821
Refer to this thread for debugging launcher issues.
Please also be aware that GUI applications on Mac ha...
What does the arrow operator, '->', do in Java?
... code I came across the arrow operator, what exactly does it do? I thought Java did not have an arrow operator.
5 Answers
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What is difference between cacerts and keystore?
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cacerts is where Java stores public certificates of root CAs. Java uses cacerts to authenticate the servers.
Keystore is where Java stores the private keys of the clients so that it can share it to the server when the server requests client ...
Compiling a java program into an executable [duplicate]
...ese ways:
(source: viralpatel.net)
1- JSmooth .exe wrapper:
JSmooth is a Java Executable Wrapper. It creates native Windows launchers (standard .exe) for your java applications. It makes java deployment much smoother and user-friendly, as it is able to find any installed Java VM by itself. When no...
How to use java.String.format in Scala?
...a .format method of a string. But if I place %1, %2, etc. in the string, java.util.UnknownFormatConversionException is thrown pointing to a confusing Java source code piece:
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Android Studio needs JDK 7 for Android-L mac
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Setting the directory to:
/Library/Java/JavaVirtualMachines/jdk1.7.0_60.jdk/Contents/Home
in JDK settings solved my issue. I had the same problem getting started up. Hope this helps!
s...