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For a boolean field, what is the naming convention for its getter/setter?

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Eg. boolean isCurrent = false; What do you name its getter and setter? Suppose you have boolean active; Accessors method would be public boolean isActive(){return this.active;} public void setActive(boolean active){this.active = active;} See Also Java Programming/Java Beans Code Conventions for the Java Programming Language Narayan http://geosoft.no/development/javastyle.html#Specific is prefix should be used for boolean variables and methods. isSet , isVisible , isFinished , isFound , isOpen This is the naming convention for boolean methods and variables used by Sun for the Java core packages

Java Spring bean with private constructor

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问题 Is possible in Spring that class for bean doesn't have public constructor but only private ? Will this private constructor invoked when bean is created? Thanks. 回答1: Yes, Spring can invoke private constructors. If it finds a constructor with the right arguments, regardless of visibility, it will use reflection to set its constructor to be accessible. 回答2: You can always use a factory method to create beans rather than relying on a default constructor, from The IoC container: Instantiation

What is a “Java Bean”? [duplicate]

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问题 This question already has answers here : What is a JavaBean exactly? (16 answers) Closed 3 years ago . The name really throws me off. I'm hoping someone can explain it in a way I won't forget :) 回答1: Any serializable java class (implementing java.io.Serializable) that follows specific conventions: a no-argument constructor, and properties accessible via get/set/is accessors. The idea is to make it predictable, so that properties etc can be discovered automatically through reflection - of

reading a dynamic property list into a spring managed bean

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问题 I've been searching but cannot find these steps. I hope I'm missing something obvious. I have a properties file with the following contents: machines=A,B I have another file like that but having a different number of members in the machines element like this: machines=B,C,D My question is how do I load this variable-length machines variable into a bean in my spring config in a generic way? something like this: <property name="machines" value="${machines}"/> where machines is an array or list

JasperReports: How to call a java bean method in report template?

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问题 I am passing a java bean collection into a jasper report. I have several fields for this java bean defined an they are display just fine in my report. Im wondering if there is a way to call a method of a java bean that is being passed into this report??? E.g. an expression for a text field, something like.... {current java bean}.methodToCall() 回答1: Using the keyword _THIS in a field name or description will make it map to the bean class itself. Using the fieldDescription tag is better as it

Java Interface Usage Guidelines — Are getters and setters in an interface bad?

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问题 What do people think of the best guidelines to use in an interface? What should and shouldn't go into an interface? I've heard people say that, as a general rule, an interface must only define behavior and not state. Does this mean that an interface shouldn't contain getters and setters? My opinion: Maybe not so for setters, but sometimes I think that getters are valid to be placed in an interface. This is merely to enforce the implementation classes to implement those getters and so to

Where is the JavaBean property naming convention defined?

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The Spring Framework API doc says: The convention used is to return the uncapitalized short name of the Class, according to JavaBeans property naming rules: So, com.myapp.Product becomes product; com.myapp.MyProduct becomes myProduct; com.myapp.UKProduct becomes UKProduct. I looked at Suns website to find a definition, but didn't find one. I wonder about a rule for names with more than one upper case character at the beginning. Is the rule that the first character is upper case if the second character is upper case too? The background is, that I want to generate variable names automatically

How to convert a Java object (bean) to key-value pairs (and vice versa)?

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Say I have a very simple java object that only has some getXXX and setXXX properties. This object is used only to handle values, basically a record or a type-safe (and performant) map. I often need to covert this object to key value pairs (either strings or type safe) or convert from key value pairs to this object. Other than reflection or manually writing code to do this conversion, what is the best way to achieve this? An example might be sending this object over jms, without using the ObjectMessage type (or converting an incoming message to the right kind of object). There is always apache

how to generically compare entire java beans?

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问题 I've been trying to grok the org.apache.commons.beanutils library for a method/idiom to evaluate for equality all properties between 2 instances i.e. a generic equals() method for beans. Is there a simple way to do this usnig this library? Or am I going about this the wrong way? Thanks. 回答1: Try EqualsBuilder.reflectionEquals() of commons-lang. EqualsBuilder has a set of methods to include all fields, all non-transient fields and all but certain fields. If all else fails, the code could serve

How to perform validation in JSF, how to create a custom validator in JSF

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I would like to perform validation in some of my input components such as <h:inputText> using some Java bean method. Should I use <f:validator> or <f:validateBean> for this? Where can I read more about it? You just need to implement the Validator interface. @FacesValidator("myValidator") public class MyValidator implements Validator { @Override public void validate(FacesContext context, UIComponent component, Object value) throws ValidatorException { // ... if (valueIsInvalid) { throw new ValidatorException(new FacesMessage("Value is invalid!")); } } } The @FacesValidator will register it to