How can I inject a property value into a Spring Bean which was configured using annotations

Question

I have a bunch of Spring beans which are picked up from the classpath via annotations  e g    Repository  personDao   public class PersonDaoImpl extends AbstractDaoImpl implements PersonDao          Implementation omitted     In the Spring XML file  there s a PropertyPlaceholderConfigurer defined    lt bean id  propertyConfigurer     class  org springframework beans factory config PropertyPlaceholderConfigurer  gt       lt property name  location  value   WEB-INF app properties    gt   lt  bean gt     I want to inject one of the properties from app properites into the bean shown above  I can t simply do something like    lt bean class  com example PersonDaoImpl  gt       lt property name  maxResults  value    results max    gt   lt  bean gt    Because PersonDaoImpl does not feature in the Spring XML file  it is picked up from the classpath via annotations   I ve got as far as the following    Repository  personDao   public class PersonDaoImpl extends AbstractDaoImpl implements PersonDao         Resource name    propertyConfigurer       protected void setProperties PropertyPlaceholderConfigurer ppc           Now how do I access results max             But it s not clear to me how I access the property I m interested in from ppc

User · Answer

Easiest way in Spring 5 is to use  ConfigurationProperties here is example https   mkyong com spring-boot spring-boot-configurationproperties-example

User · Answer

Personally I love this new way in Spring 3 0 from the docs   private  Value    propertyName    String propertyField    No getters or setters    With the properties being loaded via the config    lt bean class  org springframework beans factory config PropertyPlaceholderConfigurer        p location  classpath propertyFile properties  name  propertiesBean   gt    To further my glee I can even control click on the EL expression in IntelliJ and it brings me to the property definition   There s also the totally non xml version    PropertySource  classpath propertyFile properties   public class AppConfig         Bean     public static PropertySourcesPlaceholderConfigurer propertySourcesPlaceholderConfigurer             return new PropertySourcesPlaceholderConfigurer

User · Answer

Before we get Spring 3 - which allows you to inject property constants directly into your beans using annotations - I wrote a sub-class of the PropertyPlaceholderConfigurer bean that does the same thing  So  you can mark up your property setters and Spring will autowire your properties into your beans like so    Property key  property key   defaultValue  default   public void setProperty String property        this property   property      The Annotation is as follows    Retention RetentionPolicy RUNTIME    Target  ElementType METHOD  ElementType FIELD   public  interface Property       String key        String defaultValue   default         The PropertyAnnotationAndPlaceholderConfigurer is as follows   public class PropertyAnnotationAndPlaceholderConfigurer extends PropertyPlaceholderConfigurer        private static Logger log   Logger getLogger PropertyAnnotationAndPlaceholderConfigurer class         Override     protected void processProperties ConfigurableListableBeanFactory beanFactory  Properties properties  throws BeansException           super processProperties beanFactory  properties            for  String name   beanFactory getBeanDefinitionNames                  MutablePropertyValues mpv   beanFactory getBeanDefinition name  getPropertyValues                Class clazz   beanFactory getType name                if log isDebugEnabled    log debug  Configuring properties for bean   name     clazz                    if clazz    null                    for  PropertyDescriptor property   BeanUtils getPropertyDescriptors clazz                         Method setter   property getWriteMethod                        Method getter   property getReadMethod                        Property annotation   null                      if setter    null  amp  amp  setter isAnnotationPresent Property class                             annotation   setter getAnnotation Property class                         else if setter    null  amp  amp  getter    null  amp  amp  getter isAnnotationPresent Property class                             annotation   getter getAnnotation Property class                                             if annotation    null                            String value   resolvePlaceholder annotation key    properties  SYSTEM PROPERTIES MODE FALLBACK                           if StringUtils isEmpty value                                 value   annotation defaultValue                                                      if StringUtils isEmpty value                                 throw new BeanConfigurationException  No such property    annotation key      found in properties                                                       if log isDebugEnabled    log debug  setting property    clazz getName       property getName      value    annotation key       value                               mpv addPropertyValue property getName    value                                                            for Field field   clazz getDeclaredFields                          if log isDebugEnabled    log debug  examining field    clazz getName       field getName                             if field isAnnotationPresent Property class                             Property annotation   field getAnnotation Property class                           PropertyDescriptor property   BeanUtils getPropertyDescriptor clazz  field getName                              if property getWriteMethod      null                                throw new BeanConfigurationException  setter for property    clazz getName       field getName      not available                                                        Object value   resolvePlaceholder annotation key    properties  SYSTEM PROPERTIES MODE FALLBACK                           if value    null                                value   annotation defaultValue                                                      if value    null                                throw new BeanConfigurationException  No such property    annotation key      found in properties                                                       if log isDebugEnabled    log debug  setting property    clazz getName       field getName      value    annotation key       value                               mpv addPropertyValue property getName    value                                                                              Feel free to modify to taste

User · Answer

Use Spring s  PropertyPlaceholderConfigurer  class   A simple example showing property file read dynamically as bean s property   lt bean id  placeholderConfig          class  org springframework beans factory config PropertyPlaceholderConfigurer  gt       lt property name  locations  gt           lt list gt               lt value gt  WEB-INF classes config properties dev database properties lt  value gt           lt  list gt       lt  property gt    lt  bean gt    lt bean id  devDataSource  class  com mchange v2 c3p0 ComboPooledDataSource  destroy-method  close  gt       lt property name  driverClass  value    dev app jdbc driver    gt       lt property name  jdbcUrl  value    dev app jdbc url    gt       lt property name  user  value    dev app jdbc username    gt       lt property name  password  value    dev app jdbc password    gt       lt property name  acquireIncrement  value  3   gt       lt property name  minPoolSize  value  5   gt       lt property name  maxPoolSize  value  10   gt       lt property name  maxStatementsPerConnection  value  11000   gt       lt property name  numHelperThreads  value  8   gt       lt property name  idleConnectionTestPeriod  value  300   gt       lt property name  preferredTestQuery  value  SELECT 0   gt   lt  bean gt     Property File  dev app jdbc driver com mysql jdbc Driver  dev app jdbc url jdbc mysql   localhost 3306 addvertisement  dev app jdbc username root  dev app jdbc password root

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A possible solutions is to declare a second bean which reads from the same properties file    lt bean id  propertyConfigurer  class  org springframework beans factory config PropertyPlaceholderConfigurer  gt       lt property name  location  value   WEB-INF app properties    gt   lt  bean gt     lt util properties id  appProperties  location  classpath  WEB-INF app properties   gt    The bean named  appProperties  is of type java util Properties and can be dependency injected using the  Resource attruibute shown above

User · Answer

Autowiring Property Values into Spring Beans   Most people know that you can use  Autowired to tell Spring to inject one object into another when it loads your application context  A lesser known nugget of information is that you can also use the  Value annotation to inject values from a property file into a bean   s attributes  see this post for more info     new stuff in Spring 3 0    autowiring bean values   autowiring property values in spring

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lt context property-placeholder       gt  is the XML equivalent to the PropertyPlaceholderConfigurer    Example  applicationContext xml   lt context property-placeholder location  classpath test properties   gt      Component class   private  Value    propertyName    String propertyField

User · Answer

You can do this in Spring 3 using EL support  Example    Value    systemProperties databaseName    public void setDatabaseName String dbName            Value    strategyBean databaseKeyGenerator    public void setKeyGenerator KeyGenerator kg            systemProperties is an implicit object and strategyBean is a bean name   One more example  which works when you want to grab a property from a Properties object  It also shows that you can apply  Value to fields    Value    myProperties  github oauth clientId      private String githubOauthClientId    Here is a blog post I wrote about this for a little more info

User · Answer

There is a new annotation  Value in Spring 3 0 0M3   Value support not only        expressions but        placeholders as well

User · Answer

I need to have two properties files  one for production and an override for development  that will not be deployed     To have both  a Properties Bean that can be autowired and a PropertyConfigurer  you can write    lt bean id  appProperties  class  org springframework beans factory config PropertiesFactoryBean  gt       lt property name  singleton  value  true    gt        lt property name  ignoreResourceNotFound  value  true    gt       lt property name  locations  gt           lt list gt               lt value gt classpath live properties lt  value gt               lt value gt classpath development properties lt  value gt           lt  list gt       lt  property gt   lt  bean gt    and reference the Properties Bean in the PropertyConfigurer   lt bean id  propertyConfigurer  class  org springframework beans factory config PropertyPlaceholderConfigurer  gt       lt property name  properties  ref  appProperties    gt   lt  bean gt

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Another alternative is to add the appProperties bean shown below    lt bean id  propertyConfigurer       class  org springframework beans factory config PropertyPlaceholderConfigurer  gt           lt property name  location  value   WEB-INF app properties    gt   lt  bean gt      lt bean id  appProperties             class  org springframework beans factory config PropertiesFactoryBean  gt           lt property name  singleton  value  true   gt            lt property name  properties  gt                   lt props gt                           lt prop key  results max  gt   results max  lt  prop gt                   lt  props gt           lt  property gt   lt  bean gt    When retrieved  this bean can be cast to a java util Properties which will contain a property named results max whose value is read from app properties  Again  this bean can be dependency injected  as an instance of java util Properties  into any class via the  Resource annotation   Personally  I prefer this solution  to the other I proposed   as you can limit exactly which properties are exposed by appProperties  and don t need to read app properties twice

User · Answer

Autowiring Property Values into Spring Beans   Most people know that you can use  Autowired to tell Spring to inject one object into another when it loads your application context  A lesser known nugget of information is that you can also use the  Value annotation to inject values from a property file into a bean   s attributes  see this post for more info     new stuff in Spring 3 0    autowiring bean values   autowiring property values in spring

User · Answer

I think it s most convenient way to inject properties into bean is setter method   Example   package org some beans   public class MyBean       Long id      String name       public void setId Long id            this id   id             public Long getId             return id             public void setName String name            this name   name             public String getName             return name            Bean xml definition    lt bean id  Bean1  class  org some beans MyBean  gt       lt property name  id  value  1   gt       lt property name  name  value  MyBean   gt   lt  bean gt    For every named property method setProperty value  will be invoked   This way is especially helpful if you need more than one bean based on one implementation   For example  if we define one more bean in xml    lt bean id  Bean2  class  org some beans MyBean  gt       lt property name  id  value  2   gt       lt property name  name  value  EnotherBean   gt   lt  bean gt    Then code like this   MyBean b1   appContext getBean  Bean1    System out println  Bean id       b1 getId       name       b1 getName     MyBean b2   appContext getBean  Bean2    System out println  Bean id       b2 getId       name       b2 getName       Will print  Bean id   1 name   MyBean Bean id   2 name   AnotherBean   So  in your case it should look like this    Repository  personDao   public class PersonDaoImpl extends AbstractDaoImpl implements PersonDao        Long maxResults       public void setMaxResults Long maxResults            this maxResults   maxResults                Now use maxResults value in your code  it will be injected on Bean creation     public void someMethod Long results            if  results  lt  maxResults

User · Answer

There is a new annotation  Value in Spring 3 0 0M3   Value support not only        expressions but        placeholders as well

User · Answer

If you need more Flexibility for the configurations  try the Settings4jPlaceholderConfigurer  http   settings4j sourceforge net currentrelease configSpringPlaceholder html  In our application we use    Preferences to configure the PreProd- and Prod-System Preferences and JNDI Environment variables  JNDI overwrites the preferences  for  mvn jetty run  System Properties for UnitTests   BeforeClass annotation    The default order which key-value-Source is checked first  is described in  http   settings4j sourceforge net currentrelease configDefault html  It can be customized with a settings4j xml  accurate to log4j xml  in your classpath   Let me know your opinion  settings4j-user lists sourceforge net  with friendly regards   Harald

User · Answer

As mentioned  Value does the job and it is quite flexible as you can have spring EL in it   Here are some examples  which could be helpful     Build and array from comma separated parameters    Like currency codes list 10 11 12 13  Value       currency codes list   split          private List lt String gt  currencyTypes    Another to get a set from a list    If you have a list of some objects like  List lt BranchVO gt      and the BranchVO has areaCode cityCode       You can easily make a set or areaCodes as below  Value    BranchList   areaCode      private Set lt String gt  areas    You can also set values for primitive types    Value    amount limit    private int amountLimit    You can call static methods    Value    T foo bar  isSecurityEnabled      private boolean securityEnabled    You can have logic   Value    T foo bar  isSecurityEnabled        security logo path        default logo path      private String logoPath

User · Answer

Easiest way in Spring 5 is to use  ConfigurationProperties here is example https   mkyong com spring-boot spring-boot-configurationproperties-example

User · Answer

Spring way  private  Value    propertyName     String propertyField   is a new way to inject the value using Spring s  PropertyPlaceholderConfigurer  class   Another way is to call  java util Properties props   System getProperties   getProperty  propertyName      Note  For  Value  you can not use static propertyField  it should be non-static only  otherwise it returns null  To fix it a non static setter is created for the static field and  Value is applied above that setter

User · Answer

Another alternative is to add the appProperties bean shown below    lt bean id  propertyConfigurer       class  org springframework beans factory config PropertyPlaceholderConfigurer  gt           lt property name  location  value   WEB-INF app properties    gt   lt  bean gt      lt bean id  appProperties             class  org springframework beans factory config PropertiesFactoryBean  gt           lt property name  singleton  value  true   gt            lt property name  properties  gt                   lt props gt                           lt prop key  results max  gt   results max  lt  prop gt                   lt  props gt           lt  property gt   lt  bean gt    When retrieved  this bean can be cast to a java util Properties which will contain a property named results max whose value is read from app properties  Again  this bean can be dependency injected  as an instance of java util Properties  into any class via the  Resource annotation   Personally  I prefer this solution  to the other I proposed   as you can limit exactly which properties are exposed by appProperties  and don t need to read app properties twice

User · Answer

Another alternative is to add the appProperties bean shown below    lt bean id  propertyConfigurer       class  org springframework beans factory config PropertyPlaceholderConfigurer  gt           lt property name  location  value   WEB-INF app properties    gt   lt  bean gt      lt bean id  appProperties             class  org springframework beans factory config PropertiesFactoryBean  gt           lt property name  singleton  value  true   gt            lt property name  properties  gt                   lt props gt                           lt prop key  results max  gt   results max  lt  prop gt                   lt  props gt           lt  property gt   lt  bean gt    When retrieved  this bean can be cast to a java util Properties which will contain a property named results max whose value is read from app properties  Again  this bean can be dependency injected  as an instance of java util Properties  into any class via the  Resource annotation   Personally  I prefer this solution  to the other I proposed   as you can limit exactly which properties are exposed by appProperties  and don t need to read app properties twice

User · Answer

A possible solutions is to declare a second bean which reads from the same properties file    lt bean id  propertyConfigurer  class  org springframework beans factory config PropertyPlaceholderConfigurer  gt       lt property name  location  value   WEB-INF app properties    gt   lt  bean gt     lt util properties id  appProperties  location  classpath  WEB-INF app properties   gt    The bean named  appProperties  is of type java util Properties and can be dependency injected using the  Resource attruibute shown above

User · Answer

If you are stuck using Spring 2 5 you could define a bean for each of your properties and inject them using qualifiers   Like this      lt bean id  someFile  class  java io File  gt       lt constructor-arg value    someFile    gt     lt  bean gt    and    Service public class Thing       public Thing  Qualifier  someFile   File someFile          Its not super readable but it gets the job done

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For me  it was  Lucky s answer  and specifically  the line  AutowiredFakaSource fakeDataSource   ctx getBean AutowiredFakaSource class     from the Captain Debug page  that fixed my problem  I have an ApplicationContext-based app running from the command-line  and judging by a number of the comments on SO  Spring wires up these differently to MVC-based apps

User · Answer

If you need more Flexibility for the configurations  try the Settings4jPlaceholderConfigurer  http   settings4j sourceforge net currentrelease configSpringPlaceholder html  In our application we use    Preferences to configure the PreProd- and Prod-System Preferences and JNDI Environment variables  JNDI overwrites the preferences  for  mvn jetty run  System Properties for UnitTests   BeforeClass annotation    The default order which key-value-Source is checked first  is described in  http   settings4j sourceforge net currentrelease configDefault html  It can be customized with a settings4j xml  accurate to log4j xml  in your classpath   Let me know your opinion  settings4j-user lists sourceforge net  with friendly regards   Harald

User · Answer

If you are stuck using Spring 2 5 you could define a bean for each of your properties and inject them using qualifiers   Like this      lt bean id  someFile  class  java io File  gt       lt constructor-arg value    someFile    gt     lt  bean gt    and    Service public class Thing       public Thing  Qualifier  someFile   File someFile          Its not super readable but it gets the job done

User · Answer

You also can annotate you class    PropertySource  classpath  com myProject config properties database properties     And have a variable like this    Autowired private Environment env    Now you can access to all your properties in this way   env getProperty  database connection driver

User · Answer

Spring way  private  Value    propertyName     String propertyField   is a new way to inject the value using Spring s  PropertyPlaceholderConfigurer  class   Another way is to call  java util Properties props   System getProperties   getProperty  propertyName      Note  For  Value  you can not use static propertyField  it should be non-static only  otherwise it returns null  To fix it a non static setter is created for the static field and  Value is applied above that setter

User · Answer

For me  it was  Lucky s answer  and specifically  the line  AutowiredFakaSource fakeDataSource   ctx getBean AutowiredFakaSource class     from the Captain Debug page  that fixed my problem  I have an ApplicationContext-based app running from the command-line  and judging by a number of the comments on SO  Spring wires up these differently to MVC-based apps

User · Answer

I need to have two properties files  one for production and an override for development  that will not be deployed     To have both  a Properties Bean that can be autowired and a PropertyConfigurer  you can write    lt bean id  appProperties  class  org springframework beans factory config PropertiesFactoryBean  gt       lt property name  singleton  value  true    gt        lt property name  ignoreResourceNotFound  value  true    gt       lt property name  locations  gt           lt list gt               lt value gt classpath live properties lt  value gt               lt value gt classpath development properties lt  value gt           lt  list gt       lt  property gt   lt  bean gt    and reference the Properties Bean in the PropertyConfigurer   lt bean id  propertyConfigurer  class  org springframework beans factory config PropertyPlaceholderConfigurer  gt       lt property name  properties  ref  appProperties    gt   lt  bean gt

User · Answer

lt context property-placeholder       gt  is the XML equivalent to the PropertyPlaceholderConfigurer    Example  applicationContext xml   lt context property-placeholder location  classpath test properties   gt      Component class   private  Value    propertyName    String propertyField

User · Answer

You can do this in Spring 3 using EL support  Example    Value    systemProperties databaseName    public void setDatabaseName String dbName            Value    strategyBean databaseKeyGenerator    public void setKeyGenerator KeyGenerator kg            systemProperties is an implicit object and strategyBean is a bean name   One more example  which works when you want to grab a property from a Properties object  It also shows that you can apply  Value to fields    Value    myProperties  github oauth clientId      private String githubOauthClientId    Here is a blog post I wrote about this for a little more info

User · Answer

I need to have two properties files  one for production and an override for development  that will not be deployed     To have both  a Properties Bean that can be autowired and a PropertyConfigurer  you can write    lt bean id  appProperties  class  org springframework beans factory config PropertiesFactoryBean  gt       lt property name  singleton  value  true    gt        lt property name  ignoreResourceNotFound  value  true    gt       lt property name  locations  gt           lt list gt               lt value gt classpath live properties lt  value gt               lt value gt classpath development properties lt  value gt           lt  list gt       lt  property gt   lt  bean gt    and reference the Properties Bean in the PropertyConfigurer   lt bean id  propertyConfigurer  class  org springframework beans factory config PropertyPlaceholderConfigurer  gt       lt property name  properties  ref  appProperties    gt   lt  bean gt

User · Answer

You can do this in Spring 3 using EL support  Example    Value    systemProperties databaseName    public void setDatabaseName String dbName            Value    strategyBean databaseKeyGenerator    public void setKeyGenerator KeyGenerator kg            systemProperties is an implicit object and strategyBean is a bean name   One more example  which works when you want to grab a property from a Properties object  It also shows that you can apply  Value to fields    Value    myProperties  github oauth clientId      private String githubOauthClientId    Here is a blog post I wrote about this for a little more info

User · Answer

You also can annotate you class    PropertySource  classpath  com myProject config properties database properties     And have a variable like this    Autowired private Environment env    Now you can access to all your properties in this way   env getProperty  database connection driver

User · Answer

Another alternative is to add the appProperties bean shown below    lt bean id  propertyConfigurer       class  org springframework beans factory config PropertyPlaceholderConfigurer  gt           lt property name  location  value   WEB-INF app properties    gt   lt  bean gt      lt bean id  appProperties             class  org springframework beans factory config PropertiesFactoryBean  gt           lt property name  singleton  value  true   gt            lt property name  properties  gt                   lt props gt                           lt prop key  results max  gt   results max  lt  prop gt                   lt  props gt           lt  property gt   lt  bean gt    When retrieved  this bean can be cast to a java util Properties which will contain a property named results max whose value is read from app properties  Again  this bean can be dependency injected  as an instance of java util Properties  into any class via the  Resource annotation   Personally  I prefer this solution  to the other I proposed   as you can limit exactly which properties are exposed by appProperties  and don t need to read app properties twice

User · Answer

Use Spring s  PropertyPlaceholderConfigurer  class   A simple example showing property file read dynamically as bean s property   lt bean id  placeholderConfig          class  org springframework beans factory config PropertyPlaceholderConfigurer  gt       lt property name  locations  gt           lt list gt               lt value gt  WEB-INF classes config properties dev database properties lt  value gt           lt  list gt       lt  property gt    lt  bean gt    lt bean id  devDataSource  class  com mchange v2 c3p0 ComboPooledDataSource  destroy-method  close  gt       lt property name  driverClass  value    dev app jdbc driver    gt       lt property name  jdbcUrl  value    dev app jdbc url    gt       lt property name  user  value    dev app jdbc username    gt       lt property name  password  value    dev app jdbc password    gt       lt property name  acquireIncrement  value  3   gt       lt property name  minPoolSize  value  5   gt       lt property name  maxPoolSize  value  10   gt       lt property name  maxStatementsPerConnection  value  11000   gt       lt property name  numHelperThreads  value  8   gt       lt property name  idleConnectionTestPeriod  value  300   gt       lt property name  preferredTestQuery  value  SELECT 0   gt   lt  bean gt     Property File  dev app jdbc driver com mysql jdbc Driver  dev app jdbc url jdbc mysql   localhost 3306 addvertisement  dev app jdbc username root  dev app jdbc password root

User · Answer

You can do this in Spring 3 using EL support  Example    Value    systemProperties databaseName    public void setDatabaseName String dbName            Value    strategyBean databaseKeyGenerator    public void setKeyGenerator KeyGenerator kg            systemProperties is an implicit object and strategyBean is a bean name   One more example  which works when you want to grab a property from a Properties object  It also shows that you can apply  Value to fields    Value    myProperties  github oauth clientId      private String githubOauthClientId    Here is a blog post I wrote about this for a little more info

User · Answer

Personally I love this new way in Spring 3 0 from the docs   private  Value    propertyName    String propertyField    No getters or setters    With the properties being loaded via the config    lt bean class  org springframework beans factory config PropertyPlaceholderConfigurer        p location  classpath propertyFile properties  name  propertiesBean   gt    To further my glee I can even control click on the EL expression in IntelliJ and it brings me to the property definition   There s also the totally non xml version    PropertySource  classpath propertyFile properties   public class AppConfig         Bean     public static PropertySourcesPlaceholderConfigurer propertySourcesPlaceholderConfigurer             return new PropertySourcesPlaceholderConfigurer

User · Answer

A possible solutions is to declare a second bean which reads from the same properties file    lt bean id  propertyConfigurer  class  org springframework beans factory config PropertyPlaceholderConfigurer  gt       lt property name  location  value   WEB-INF app properties    gt   lt  bean gt     lt util properties id  appProperties  location  classpath  WEB-INF app properties   gt    The bean named  appProperties  is of type java util Properties and can be dependency injected using the  Resource attruibute shown above

User · Answer

As mentioned  Value does the job and it is quite flexible as you can have spring EL in it   Here are some examples  which could be helpful     Build and array from comma separated parameters    Like currency codes list 10 11 12 13  Value       currency codes list   split          private List lt String gt  currencyTypes    Another to get a set from a list    If you have a list of some objects like  List lt BranchVO gt      and the BranchVO has areaCode cityCode       You can easily make a set or areaCodes as below  Value    BranchList   areaCode      private Set lt String gt  areas    You can also set values for primitive types    Value    amount limit    private int amountLimit    You can call static methods    Value    T foo bar  isSecurityEnabled      private boolean securityEnabled    You can have logic   Value    T foo bar  isSecurityEnabled        security logo path        default logo path      private String logoPath

User · Answer

I think it s most convenient way to inject properties into bean is setter method   Example   package org some beans   public class MyBean       Long id      String name       public void setId Long id            this id   id             public Long getId             return id             public void setName String name            this name   name             public String getName             return name            Bean xml definition    lt bean id  Bean1  class  org some beans MyBean  gt       lt property name  id  value  1   gt       lt property name  name  value  MyBean   gt   lt  bean gt    For every named property method setProperty value  will be invoked   This way is especially helpful if you need more than one bean based on one implementation   For example  if we define one more bean in xml    lt bean id  Bean2  class  org some beans MyBean  gt       lt property name  id  value  2   gt       lt property name  name  value  EnotherBean   gt   lt  bean gt    Then code like this   MyBean b1   appContext getBean  Bean1    System out println  Bean id       b1 getId       name       b1 getName     MyBean b2   appContext getBean  Bean2    System out println  Bean id       b2 getId       name       b2 getName       Will print  Bean id   1 name   MyBean Bean id   2 name   AnotherBean   So  in your case it should look like this    Repository  personDao   public class PersonDaoImpl extends AbstractDaoImpl implements PersonDao        Long maxResults       public void setMaxResults Long maxResults            this maxResults   maxResults                Now use maxResults value in your code  it will be injected on Bean creation     public void someMethod Long results            if  results  lt  maxResults

User · Answer

Before we get Spring 3 - which allows you to inject property constants directly into your beans using annotations - I wrote a sub-class of the PropertyPlaceholderConfigurer bean that does the same thing  So  you can mark up your property setters and Spring will autowire your properties into your beans like so    Property key  property key   defaultValue  default   public void setProperty String property        this property   property      The Annotation is as follows    Retention RetentionPolicy RUNTIME    Target  ElementType METHOD  ElementType FIELD   public  interface Property       String key        String defaultValue   default         The PropertyAnnotationAndPlaceholderConfigurer is as follows   public class PropertyAnnotationAndPlaceholderConfigurer extends PropertyPlaceholderConfigurer        private static Logger log   Logger getLogger PropertyAnnotationAndPlaceholderConfigurer class         Override     protected void processProperties ConfigurableListableBeanFactory beanFactory  Properties properties  throws BeansException           super processProperties beanFactory  properties            for  String name   beanFactory getBeanDefinitionNames                  MutablePropertyValues mpv   beanFactory getBeanDefinition name  getPropertyValues                Class clazz   beanFactory getType name                if log isDebugEnabled    log debug  Configuring properties for bean   name     clazz                    if clazz    null                    for  PropertyDescriptor property   BeanUtils getPropertyDescriptors clazz                         Method setter   property getWriteMethod                        Method getter   property getReadMethod                        Property annotation   null                      if setter    null  amp  amp  setter isAnnotationPresent Property class                             annotation   setter getAnnotation Property class                         else if setter    null  amp  amp  getter    null  amp  amp  getter isAnnotationPresent Property class                             annotation   getter getAnnotation Property class                                             if annotation    null                            String value   resolvePlaceholder annotation key    properties  SYSTEM PROPERTIES MODE FALLBACK                           if StringUtils isEmpty value                                 value   annotation defaultValue                                                      if StringUtils isEmpty value                                 throw new BeanConfigurationException  No such property    annotation key      found in properties                                                       if log isDebugEnabled    log debug  setting property    clazz getName       property getName      value    annotation key       value                               mpv addPropertyValue property getName    value                                                            for Field field   clazz getDeclaredFields                          if log isDebugEnabled    log debug  examining field    clazz getName       field getName                             if field isAnnotationPresent Property class                             Property annotation   field getAnnotation Property class                           PropertyDescriptor property   BeanUtils getPropertyDescriptor clazz  field getName                              if property getWriteMethod      null                                throw new BeanConfigurationException  setter for property    clazz getName       field getName      not available                                                        Object value   resolvePlaceholder annotation key    properties  SYSTEM PROPERTIES MODE FALLBACK                           if value    null                                value   annotation defaultValue                                                      if value    null                                throw new BeanConfigurationException  No such property    annotation key      found in properties                                                       if log isDebugEnabled    log debug  setting property    clazz getName       field getName      value    annotation key       value                               mpv addPropertyValue property getName    value                                                                              Feel free to modify to taste

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A possible solutions is to declare a second bean which reads from the same properties file    lt bean id  propertyConfigurer  class  org springframework beans factory config PropertyPlaceholderConfigurer  gt       lt property name  location  value   WEB-INF app properties    gt   lt  bean gt     lt util properties id  appProperties  location  classpath  WEB-INF app properties   gt    The bean named  appProperties  is of type java util Properties and can be dependency injected using the  Resource attruibute shown above

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I need to have two properties files  one for production and an override for development  that will not be deployed     To have both  a Properties Bean that can be autowired and a PropertyConfigurer  you can write    lt bean id  appProperties  class  org springframework beans factory config PropertiesFactoryBean  gt       lt property name  singleton  value  true    gt        lt property name  ignoreResourceNotFound  value  true    gt       lt property name  locations  gt           lt list gt               lt value gt classpath live properties lt  value gt               lt value gt classpath development properties lt  value gt           lt  list gt       lt  property gt   lt  bean gt    and reference the Properties Bean in the PropertyConfigurer   lt bean id  propertyConfigurer  class  org springframework beans factory config PropertyPlaceholderConfigurer  gt       lt property name  properties  ref  appProperties    gt   lt  bean gt

[java] How can I inject a property value into a Spring Bean which was configured using annotations?

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