value-of

String.valueOf(someVar) vs (“” + someVar) [duplicate]

眉间皱痕 提交于 2021-01-27 21:39:01
问题 This question already has answers here : String valueOf vs concatenation with empty string (10 answers) Closed 3 years ago . I want to know the difference in two approaches. There are some old codes on which I'm working now, where they are setting primitive values to a String value by concatenating with an empty String "" . obj.setSomeString("" + primitiveVariable); But in this link Size of empty Java String it says that If you're creating a separate empty string for each instance, then

How can i insert timestamp with timezone in postgresql with prepared statement?

只愿长相守 提交于 2019-12-22 03:25:32
问题 I am trying to insert to a timestamp with timezone field of my DB a string which includes date, time and timezone using prepared statement. The problem is that Timestamp.valueof function does not take into consideration the time zone that the string inludes so it causes an error. The accepted format is yyyy-[m]m-[d]d hh:mm:ss[.f...] which does not mention timezone. That is the exact code that causes the error: pst.setTimestamp(2,Timestamp.valueOf("2012-08-24 14:00:00 +02:00")) Is there any

xsl:value-of used as xsl:element name

我是研究僧i 提交于 2019-12-12 07:14:03
问题 I have an incoming XML file with a list structure: <list> <listItem> <name>elementOne</name> <value>elementOneValue</name> </listItem> <listItem> <name>elementTwo</name> <value>elementTwoValue</name> </listItem> </list> Which I am trying to convert to this structure: <elementOne>elementOneValue</elementOne> <elementTwo>elementTwoValue</elementTwo> This is easy logic to implement with XSL, but I'm running into complications. <xsl:for-each select="/list/listItem"> <xsl:element name="<xsl:value

Thread safety of enum valueOf()

孤街浪徒 提交于 2019-12-08 06:46:25
问题 This is a variation of the perpertual "lengthy-if or switch" dilemma... Consider a multithreaded application using a static method that contains a long (over a dozen conditions) if statement, which checks the type of an object and returns a value accordingly, i.e. something like public static String checkType(Class<?> type) { if (type == A.class) { return aString; } else if (type == B.class) { return bString; } ... else if (type == z.class) { return zString; } } Obviously a switch statement

Significance of valueOf() in javascript

混江龙づ霸主 提交于 2019-12-02 07:19:37
I have noticed the snippet_1 in the implementation of one of the Node API's. Snippet_2 has been written by me. I don't feel much difference between them. Is there really any significance of using valueOf() function. And also, we can notice a property called as valueOf which would return [Function: valueOf] Snippet_1 Buffer.from = function from(value, encodingOrOffset, length) { const valueOf = value.valueOf && value.valueOf(); if (valueOf !== null && valueOf !== undefined && valueOf !== value) return Buffer.from(valueOf, encodingOrOffset, length); } Snippet_2 Buffer.from = function from(value,

Significance of valueOf() in javascript

两盒软妹~` 提交于 2019-12-02 06:43:36
问题 I have noticed the snippet_1 in the implementation of one of the Node API's. Snippet_2 has been written by me. I don't feel much difference between them. Is there really any significance of using valueOf() function. And also, we can notice a property called as valueOf which would return [Function: valueOf] Snippet_1 Buffer.from = function from(value, encodingOrOffset, length) { const valueOf = value.valueOf && value.valueOf(); if (valueOf !== null && valueOf !== undefined && valueOf !== value

Where does the Enum.valueOf(String) method come from?

馋奶兔 提交于 2019-11-28 21:11:50
In Java SE 7 (and most probably in previous versions) the Enum class is declared like this: public abstract class Enum<E extends Enum<E>> extends Object implements Comparable<E>, Serializable The Enum class has a static method with this signature: T static<T extends Enum<T>> valueOf(Class<T> enumType, String name) But there is no static method : valueOf(String) defined in the Enum class nor upwards in the hierarchy Enum belongs to. The question is where does valueOf(String) come from ? Is it a feature of the language, i.e. a feature built in the compiler ? This method is implicitly defined by

Differences between new Integer(123), Integer.valueOf(123) and just 123

让人想犯罪 __ 提交于 2019-11-27 19:02:40
Recenlty I saw code (Java) like this: myMethod(new Integer(123)); I am currently refactoring some code, and there is a tip in Sonar tool, that it's more memory friendly to use sth like this: myMethod(Integer.valueOf(123)); However in this case, I think that there is no difference if I would use: myMethod(123); I could understand that, if I would pass a variable to the method, but hard coded int? Or if there would be Long/Double etc and I want Long representation of number. But integer? new Integer(123) will create a new Object instance for each call. According to the javadoc , Integer.valueOf

Where does the Enum.valueOf(String) method come from?

倾然丶 夕夏残阳落幕 提交于 2019-11-27 13:46:52
问题 In Java SE 7 (and most probably in previous versions) the Enum class is declared like this: public abstract class Enum<E extends Enum<E>> extends Object implements Comparable<E>, Serializable The Enum class has a static method with this signature: T static<T extends Enum<T>> valueOf(Class<T> enumType, String name) But there is no static method : valueOf(String) defined in the Enum class nor upwards in the hierarchy Enum belongs to. The question is where does valueOf(String) come from ? Is it

Override valueof() and toString() in Java enum

烈酒焚心 提交于 2019-11-27 07:09:10
The values in my enum are words that need to have spaces in them, but enums can't have spaces in their values so it's all bunched up. I want to override toString() to add these spaces where I tell it to. I also want the enum to provide the correct enum when I use valueOf() on the same string that I added the spaces to. For example: public enum RandomEnum { StartHere, StopHere } Call toString() on RandomEnum whose value is StartHere returns string "Start Here" . Call valueof() on that same string ( "Start Here" ) returns enum value StartHere . How can I do this? You can try out this code. Since