org.argeo.slc.agent/src/main/java/org/argeo/slc/ant/spring/SpringArg.java

   1 package org.argeo.slc.ant.spring;
   2
   3 import java.util.List;
   4 import java.util.Vector;
   5
   6 import org.apache.tools.ant.BuildException;
   7 import org.apache.tools.ant.types.DataType;
   8 import org.argeo.slc.ant.AntConstants;
   9 import org.argeo.slc.core.SlcException;
  10 import org.springframework.beans.BeanWrapper;
  11 import org.springframework.beans.BeanWrapperImpl;
  12 import org.springframework.beans.factory.InitializingBean;
  13 import org.springframework.context.ApplicationContext;
  14
  15 /** Abstract Ant type wrapping a Spring bean. */
  16 public class SpringArg<T> extends DataType {
  17         private List<OverrideArg> overrides = new Vector<OverrideArg>();
  18
  19         private String bean;
  20         private String antref;
  21
  22         // cache bean instance to avoid reading it twice if it is a prototype
  23         private T beanInstance = null;
  24
  25         /** The <u>name</u> of the underlying bean, as set through the attribute. */
  26         public String getBean() {
  27                 return bean;
  28         }
  29
  30         /** Setter for the bean name. */
  31         public void setBean(String bean) {
  32                 checkValueAlreadySet();
  33                 this.bean = bean;
  34         }
  35
  36         public String getAntref() {
  37                 return antref;
  38         }
  39
  40         /** Sets a reference to an ant data type. */
  41         public void setAntref(String antref) {
  42                 checkValueAlreadySet();
  43                 this.antref = antref;
  44         }
  45
  46         /**
  47          * Retrieve the instance of the bean, and sets the overridden properties.
  48          * <b>The value is cached.</b>
  49          */
  50         public T getBeanInstance() {
  51                 if (beanInstance == null) {
  52                         if (bean != null) {
  53                                 beanInstance = (T) getContext().getBean(bean);
  54                                 if (beanInstance == null)
  55                                         throw new SlcException("No object found for Spring bean "
  56                                                         + bean);
  57                         } else if (antref != null) {
  58                                 beanInstance = (T) getProject().getReference(antref);
  59                                 if (beanInstance == null)
  60                                         throw new SlcException("No object found for Ant reference "
  61                                                         + antref);
  62                         } else {
  63                                 throw new SlcException(
  64                                                 "Don't know how to retrieve bean instance");
  65                         }
  66
  67                         setOverridenProperties(beanInstance);
  68
  69                         // FIXME: why are we doing this? Could not find any object using it
  70                         if (beanInstance instanceof InitializingBean) {
  71                                 try {
  72                                         ((InitializingBean) beanInstance).afterPropertiesSet();
  73                                 } catch (Exception e) {
  74                                         throw new SlcException("Could not initialize bean", e);
  75                                 }
  76                         }
  77                 }
  78                 return beanInstance;
  79         }
  80
  81         protected void setOverridenProperties(Object obj) {
  82                 BeanWrapper wrapper = new BeanWrapperImpl(obj);
  83                 for (OverrideArg override : overrides) {
  84                         if (override.getName() == null) {
  85                                 throw new SlcException(
  86                                                 "The name of the property to override has to be set.");
  87                         }
  88
  89                         // LogFactory.getLog(getClass()).debug(
  90                         // "Prop " + override.getName());
  91                         wrapper.setPropertyValue(override.getName(), override.getObject());
  92                 }
  93
  94         }
  95
  96         /** Creates an override subtag. */
  97         public OverrideArg createOverride() {
  98                 OverrideArg propertyArg = new OverrideArg();
  99                 overrides.add(propertyArg);
 100                 return propertyArg;
 101         }
 102
 103         /** The related Spring application context. */
 104         protected ApplicationContext getContext() {
 105                 return (ApplicationContext) getProject().getReference(
 106                                 AntConstants.REF_ROOT_CONTEXT);
 107         }
 108
 109         protected void checkValueAlreadySet() {
 110                 if (antref != null || bean != null) {
 111                         throw new BuildException("Value already set.");
 112                 }
 113         }
 114
 115 }