There is couple ways about doing that, you could use JBoss EL expression implementation they support method calls with parameters check out Seam, or use similar approach as @digitaljoel suggested.
This is what I created for that purpose, you can call static and static methods, not a great solution but it does the job.
Hello Panel
@Util is just an alias to com.mycomp.util where
**Example 2**
#{t:call(session, 'org.apache.catalina.session.StandardSessionFacade', 'removeAttribute', t:params(t:param(item,'')))}
t:call, t:params, t:param are function defined in project-taglib.xml as so
call
util.Functions
java.lang.Object call(java.lang.Object, java.lang.String, java.lang.String, java.lang.Object[])
param
.util.Functions
java.lang.String param(java.lang.Object, java.lang.String)
params
util.Functions
java.lang.Object[] params(java.lang.String)
Here is the implementation
package mycompany.web.util;
import java.beans.XMLDecoder;
import java.beans.XMLEncoder;
import java.io.BufferedOutputStream;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.ObjectOutputStream;
import java.io.StringWriter;
import java.lang.reflect.Array;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.Date;
import java.util.HashMap;
import java.util.List;
import javax.el.MethodNotFoundException;
public class Functions {
private static HashMap alliasMap;
static{
alliasMap=new HashMap();
alliasMap.put("@DateUtil", "com.americanbanksystems.compliance.util.DateUtil");
//Match anything following the dot(.)
alliasMap.put("@Util.*", "com.americanbanksystems.compliance.util");
alliasMap.put("@Application.*", "com.americanbanksystems.compliance.application");
}
public static String param(Object obj, String cls) {
//make sure that passed in object is not null
if(obj==null){
obj="";
}
ByteArrayOutputStream baut=new ByteArrayOutputStream();
XMLEncoder encoder=new XMLEncoder( baut );
//Bug in the JDK
//http://bugs.sun.com/bugdatabase/view_bug.do;jsessionid=c993c9a3160fd7de44075a2a1fa?bug_id=6525396
if(obj instanceof java.sql.Timestamp){
Date o = new Date(((java.sql.Timestamp)obj).getTime());
obj=o;
}
//Checking if this is possible
if(String.class.isAssignableFrom(obj.getClass())){
//removed trailing +" " because it was causing indexOf return invalid value
//Unknown side effects
obj=FacesUtil.get(obj.toString());
}
encoder.writeObject( obj );
encoder.close();
return new String(baut.toByteArray());
}
private static Object decode(String str){
ByteArrayInputStream bais=new ByteArrayInputStream(str.getBytes());
XMLDecoder decoder=new XMLDecoder(bais);
return decoder.readObject();
}
public static Object[] params(String str){
// (?<=)\s*(?=)\\s*(?=-1){
String subpackage=qualifiedClassname;
String originalClass=qualifiedClassname;
//Split at the dot
boolean isPackageAllias=false;
String[] sp=subpackage.split("\\.");
if(sp.length>1){
subpackage=sp[0]+".*";
isPackageAllias=true;
}
if(alliasMap.containsKey(subpackage)){
String value = alliasMap.get(subpackage);
if(isPackageAllias){
qualifiedClassname=subpackage.replace(sp[0], value);
qualifiedClassname=qualifiedClassname.replace(".*", originalClass.replace(sp[0],""));
}else{
qualifiedClassname=value;
}
}else{
throw new IllegalArgumentException("Allias name '"+qualifiedClassname+"' not found");
}
}
Class clazz;
try {
clazz = Class.forName(qualifiedClassname);
//Find method by methodName,Argument Types
Class[] argumentTypes=new Class[methodArguments.length];
for(int i=0;i -1) {
String arg = methodArguments[i].toString();
arg = arg.substring(2, arg.length());
try {
int outchar = Integer.parseInt(arg, 16);
if (Character.isDefined(outchar)) {
methodArguments[i] = String.valueOf((char) outchar);
}
} catch (NumberFormatException nfe) {
// Suppress error and continue assuming this is a regular string
}
}
}
Method methodToInvoke = null;
try{
methodToInvoke = clazz.getMethod(methodName, argumentTypes);
}catch(NoSuchMethodException nsm){//Find by method name/ argument count
for (Method method : clazz.getMethods()) {
if (method.getName().equals(methodName) && method.getParameterTypes().length == methodArguments.length) {
if (null == owningObject) {
owningObject = clazz.newInstance();
}
methodToInvoke=method;
break;
}
}
}
if(methodToInvoke!=null){
return methodToInvoke.invoke(owningObject, methodArguments);
}else{
throw new InstantiationException("method not found :" + methodName);
}
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (IllegalArgumentException e) {
e.printStackTrace();
} catch (IllegalAccessException e) {
e.printStackTrace();
} catch (InvocationTargetException e) {
e.printStackTrace();
} catch (InstantiationException e) {
e.printStackTrace();
}
return null;
}
public static void main(String[] arg) {
// StringBuffer buff=new StringBuffer();
// buff.append("Gregs init");
// Functions.call(java.lang.Class, T, java.lang.String, java.lang.String, java.lang.Object...)
/*
* Functions.call(StringBuffer.class, buff, "java.lang.StringBuffer","append"," Init ");
* Functions.call(StringBuffer.class, buff, "java.lang.StringBuffer","append"," greg ");
* System.out.println("output="+ buff);
*/
//#{t:call(null, ".util.DateUtil", "normalizeDate", t:parametize(editRiskActionPlan.riskActionPlan.completionDate,",","java.lang.Object"))}
// c(call(null, "util.DateUtil", "normalizeDate", new Date()));
// #{t:parametize(editRiskActionPlan.riskActionPlan.completionDate,",","java.lang.Object")}
//parametize((new Date()).toString(),",","java.lang.Object");
Date a=new Date();
Date b=new Date();
String rawString=param((Date)b, Date.class.toString() );
//System.out.println(rawString);
//Replaced=#{t:call("Gregs ' car", 'java.lang.String', 'replace', t:params( parameter ))}
String paramA=param("\\u0027","");
String paramB=param("\\u0022","");
String params=paramA+paramB;
String in="I need to ' have a replaced single quote with double";
String out=(String)call(in, "java.lang.String", "replace", params(params));
System.out.println(out);
/*
Object[] obj=params(rawString);
for(Object o:obj){
System.out.println(o);
}
//c(call(null, "@DateUtil", "normalizeDate", obj));
*/
}
}
I hope this helps, btw this was copied/pasted from my project so not sure if I missed anything.
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