大约有 40,000 项符合查询结果（耗时：0.0525秒） [XML]
What does PermGen actually stand for?
...
"In JDK 7, interned strings are no longer allocated in the permanent generation of the Java heap": oracle.com/technetwork/java/javase/jdk7-relnotes-418459.html
– almalkawi
Dec 20 '13 at 18:41
...
Rails migration: t.references with alternative name?
...
You can do this all in the initial migration/column definition (at least currently in Rails 5):
t.references :transferable_as, index: true, foreign_key: {to_table: :courses}
t.references :same_as, index: true, foreign_key: {to_table: :cours...
How do I convert from int to Long in Java?
...o Long. If you cast to long (a primitive value) then it should be automatically boxed to a Long (the reference type that wraps it).
You could alternatively use new to create an instance of Long, initializing it with the int value.
...
Getting exact error type in from DbValidationException
...ity.Validation.DbEntityValidationResult} which gives me no information at all about what field it was unable to initialize.
Is there a way to get more info about this error?
...
Why is document.body null in my javascript?
...body hasn't been defined at this point yet. In general, you want to create all elements before you execute javascript that uses these elements. In this case you have some javascript in the head section that uses body. Not cool.
You want to wrap this code in a window.onload handler or place it after...
How do I get extra data from intent on Android?
...
from where to can i all this method ??
– Adham
Nov 20 '10 at 17:06
49
...
Comprehensive beginner's virtualenv tutorial? [closed]
...'ve been hearing the buzz about virtualenv lately, and I'm interested. But all I've heard is a smattering of praise, and don't have a clear understanding of what it is or how to use it.
...
Difference between namespace in C# and package in Java
...n java you have to import a class, not a package. It IS possible to import all classes in a package with an import package.* but that too imports the classes, not the package.
– Imus
May 23 '18 at 7:54
...
How to show line number when executing bash script
...ly executing.
If you need to know the line number where the function was called, try $BASH_LINENO. Note that this variable is an array.
For example:
#!/bin/bash
function log() {
echo "LINENO: ${LINENO}"
echo "BASH_LINENO: ${BASH_LINENO[*]}"
}
function foo() {
log "$@"
}
foo ...
String.replaceAll single backslashes with double backslashes
...he String \something\ into the String \\something\\ using replaceAll , but I keep getting all kinds of errors. I thought this was the solution:
...