/*
* Copyright 2001-2004 The Apache Software Foundation.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.commons.modeler.modules;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.commons.modeler.AttributeInfo;
import org.apache.commons.modeler.ManagedBean;
import org.apache.commons.modeler.OperationInfo;
import org.apache.commons.modeler.ParameterInfo;
import org.apache.commons.modeler.Registry;
import org.apache.commons.modeler.ConstructorInfo;
import javax.management.ObjectName;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.lang.reflect.Constructor;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.List;
public class MbeansDescriptorsIntrospectionSource extends ModelerSource
{
private static Log log = LogFactory.getLog(MbeansDescriptorsIntrospectionSource.class);
Registry registry;
String location;
String type;
Object source;
List mbeans=new ArrayList();
public void setRegistry(Registry reg) {
this.registry=reg;
}
public void setLocation( String loc ) {
this.location=loc;
}
/** Used if a single component is loaded
*
* @param type
*/
public void setType( String type ) {
this.type=type;
}
public void setSource( Object source ) {
this.source=source;
}
public List loadDescriptors( Registry registry, String location,
String type, Object source)
throws Exception
{
setRegistry(registry);
setLocation(location);
setType(type);
setSource(source);
execute();
return mbeans;
}
public void execute() throws Exception {
if( registry==null ) registry=Registry.getRegistry();
try {
ManagedBean managed=createManagedBean(registry, null, (Class)source, type);
if( managed==null ) return;
managed.setName( type );
mbeans.add(managed);
} catch( Exception ex ) {
log.error( "Error reading descriptors ", ex);
}
}
// ------------ Implementation for non-declared introspection classes
static Hashtable specialMethods=new Hashtable();
static {
specialMethods.put( "preDeregister", "");
specialMethods.put( "postDeregister", "");
}
private static String strArray[]=new String[0];
private static ObjectName objNameArray[]=new ObjectName[0];
// createMBean == registerClass + registerMBean
private static Class[] supportedTypes = new Class[] {
Boolean.class,
Boolean.TYPE,
Byte.class,
Byte.TYPE,
Character.class,
Character.TYPE,
Short.class,
Short.TYPE,
Integer.class,
Integer.TYPE,
Long.class,
Long.TYPE,
Float.class,
Float.TYPE,
Double.class,
Double.TYPE,
String.class,
strArray.getClass(),
BigDecimal.class,
BigInteger.class,
ObjectName.class,
objNameArray.getClass(),
java.io.File.class,
};
/**
* Check if this class is one of the supported types.
* If the class is supported, returns true. Otherwise,
* returns false.
* @param ret The class to check
* @return boolean True if class is supported
*/
private boolean supportedType(Class ret) {
for (int i = 0; i < supportedTypes.length; i++) {
if (ret == supportedTypes[i]) {
return true;
}
}
if (isBeanCompatible(ret)) {
return true;
}
return false;
}
/**
* Check if this class conforms to JavaBeans specifications.
* If the class is conformant, returns true.
*
* @param javaType The class to check
* @return boolean True if the class is compatible.
*/
protected boolean isBeanCompatible(Class javaType) {
// Must be a non-primitive and non array
if (javaType.isArray() || javaType.isPrimitive()) {
return false;
}
// Anything in the java or javax package that
// does not have a defined mapping is excluded.
if (javaType.getName().startsWith("java.") ||
javaType.getName().startsWith("javax.")) {
return false;
}
try {
javaType.getConstructor(new Class[]{});
} catch (java.lang.NoSuchMethodException e) {
return false;
}
// Make sure superclass is compatible
Class superClass = javaType.getSuperclass();
if (superClass != null &&
superClass != java.lang.Object.class &&
superClass != java.lang.Exception.class &&
superClass != java.lang.Throwable.class) {
if (!isBeanCompatible(superClass)) {
return false;
}
}
return true;
}
/**
* Process the methods and extract 'attributes', methods, etc
*
* @param realClass The class to process
* @param methods The methods to process
* @param attMap The attribute map (complete)
* @param getAttMap The readable attributess map
* @param setAttMap The settable attributes map
* @param invokeAttMap The invokable attributes map
*/
private void initMethods(Class realClass,
Method methods[],
Hashtable attMap, Hashtable getAttMap,
Hashtable setAttMap, Hashtable invokeAttMap)
{
for (int j = 0; j < methods.length; ++j) {
String name=methods[j].getName();
if( Modifier.isStatic(methods[j].getModifiers()))
continue;
if( ! Modifier.isPublic( methods[j].getModifiers() ) ) {
if( log.isDebugEnabled())
log.debug("Not public " + methods[j] );
continue;
}
if( methods[j].getDeclaringClass() == Object.class )
continue;
Class params[]=methods[j].getParameterTypes();
if( name.startsWith( "get" ) && params.length==0) {
Class ret=methods[j].getReturnType();
if( ! supportedType( ret ) ) {
if( log.isDebugEnabled() )
log.debug("Unsupported type " + methods[j]);
continue;
}
name=unCapitalize( name.substring(3));
getAttMap.put( name, methods[j] );
// just a marker, we don't use the value
attMap.put( name, methods[j] );
} else if( name.startsWith( "is" ) && params.length==0) {
Class ret=methods[j].getReturnType();
if( Boolean.TYPE != ret ) {
if( log.isDebugEnabled() )
log.debug("Unsupported type " + methods[j] + " " + ret );
continue;
}
name=unCapitalize( name.substring(2));
getAttMap.put( name, methods[j] );
// just a marker, we don't use the value
attMap.put( name, methods[j] );
} else if( name.startsWith( "set" ) && params.length==1) {
if( ! supportedType( params[0] ) ) {
if( log.isDebugEnabled() )
log.debug("Unsupported type " + methods[j] + " " + params[0]);
continue;
}
name=unCapitalize( name.substring(3));
setAttMap.put( name, methods[j] );
attMap.put( name, methods[j] );
} else {
if( params.length == 0 ) {
if( specialMethods.get( methods[j].getName() ) != null )
continue;
invokeAttMap.put( name, methods[j]);
} else {
boolean supported=true;
for( int i=0; i<params.length; i++ ) {
if( ! supportedType( params[i])) {
supported=false;
break;
}
}
if( supported )
invokeAttMap.put( name, methods[j]);
}
}
}
}
/**
* XXX Find if the 'className' is the name of the MBean or
* the real class ( I suppose first )
* XXX Read (optional) descriptions from a .properties, generated
* from source
* XXX Deal with constructors
*
* @param registry The Bean registry (not used)
* @param domain The bean domain (not used)
* @param realClass The class to analyze
* @param type The bean type
* @return ManagedBean The create MBean
*/
public ManagedBean createManagedBean(Registry registry, String domain,
Class realClass, String type)
{
ManagedBean mbean= new ManagedBean();
Method methods[]=null;
Hashtable attMap=new Hashtable();
// key: attribute val: getter method
Hashtable getAttMap=new Hashtable();
// key: attribute val: setter method
Hashtable setAttMap=new Hashtable();
// key: operation val: invoke method
Hashtable invokeAttMap=new Hashtable();
methods = realClass.getMethods();
initMethods(realClass, methods, attMap, getAttMap, setAttMap, invokeAttMap );
try {
Enumeration en=attMap.keys();
while( en.hasMoreElements() ) {
String name=(String)en.nextElement();
AttributeInfo ai=new AttributeInfo();
ai.setName( name );
Method gm=(Method)getAttMap.get(name);
if( gm!=null ) {
//ai.setGetMethodObj( gm );
ai.setGetMethod( gm.getName());
Class t=gm.getReturnType();
if( t!=null )
ai.setType( t.getName() );
}
Method sm=(Method)setAttMap.get(name);
if( sm!=null ) {
//ai.setSetMethodObj(sm);
Class t=sm.getParameterTypes()[0];
if( t!=null )
ai.setType( t.getName());
ai.setSetMethod( sm.getName());
}
ai.setDescription("Introspected attribute " + name);
if( log.isDebugEnabled()) log.debug("Introspected attribute " +
name + " " + gm + " " + sm);
if( gm==null )
ai.setReadable(false);
if( sm==null )
ai.setWriteable(false);
if( sm!=null || gm!=null )
mbean.addAttribute(ai);
}
en=invokeAttMap.keys();
while( en.hasMoreElements() ) {
String name=(String)en.nextElement();
Method m=(Method)invokeAttMap.get(name);
if( m!=null && name != null ) {
OperationInfo op=new OperationInfo();
op.setName(name);
op.setReturnType(m.getReturnType().getName());
op.setDescription("Introspected operation " + name);
Class parms[]=m.getParameterTypes();
for(int i=0; i<parms.length; i++ ) {
ParameterInfo pi=new ParameterInfo();
pi.setType(parms[i].getName());
pi.setName( "param" + i);
pi.setDescription("Introspected parameter param" + i);
op.addParameter(pi);
}
mbean.addOperation(op);
} else {
log.error("Null arg " + name + " " + m );
}
}
Constructor[] constructors = realClass.getConstructors();
for(int i=0;i<constructors.length;i++) {
ConstructorInfo info = new ConstructorInfo();
String className = realClass.getName();
int nIndex = -1;
if((nIndex = className.lastIndexOf('.'))!=-1) {
className = className.substring(nIndex+1);
}
info.setName(className);
info.setDescription(constructors[i].getName());
Class classes[] = constructors[i].getParameterTypes();
for(int j=0;j<classes.length;j++) {
ParameterInfo pi = new ParameterInfo();
pi.setType(classes[j].getName());
pi.setName("param" + j);
pi.setDescription("Introspected parameter param" + j);
info.addParameter(pi);
}
mbean.addConstructor(info);
}
if( log.isDebugEnabled())
log.debug("Setting name: " + type );
mbean.setName( type );
return mbean;
} catch( Exception ex ) {
ex.printStackTrace();
return null;
}
}
// -------------------- Utils --------------------
/**
* Converts the first character of the given
* String into lower-case.
*
* @param name The string to convert
* @return String
*/
private static String unCapitalize(String name) {
if (name == null || name.length() == 0) {
return name;
}
char chars[] = name.toCharArray();
chars[0] = Character.toLowerCase(chars[0]);
return new String(chars);
}
}
// End of class: MbeanDescriptorsIntrospectionSource