Collection form type in Activiti

package org.activiti.engine.impl.form;

import java.util.ArrayList;

import java.util.Collection;

import java.util.HashMap;

import java.util.Map;

import org.activiti.engine.impl.form.AbstractFormType;

public class CollectionFormType<T> extends AbstractFormType {

    private Map<String, T> values = new HashMap<String, T>();

    @Override

    public String getName() {

        return "collection";

    }

    @Override

    public Collection<T> convertFormValueToModelValue(String propertyValue) { // key1|key3

        String[] ids = propertyValue.split("\\|");

        Collection<T> ret = new ArrayList<T>();

        for (String id : ids) {

            T element = values.get(id);

            if (element != null) {

                ret.add(element);

            }

        }

        return ret;

    }

    @Override

    @SuppressWarnings("unchecked")

    public String convertModelValueToFormValue(Object modelValue) {

        Collection<T> modelValues = (Collection<T>) modelValue;

        values.clear();

        for (T value : modelValues)

            values.put(value.toString(), value);

        return modelValue.toString();

    }

    @Override

    public Object getInformation(String key) {

        if ("values".equals(key)) {

            return values;

        } else {

            return null;// TODO

        }

    }

}

package org.activiti.explorer.ui.form;

import java.lang.reflect.InvocationTargetException;

import java.lang.reflect.Method;

import java.util.ArrayList;

import java.util.Collection;

import java.util.List;

import java.util.Map;

import org.activiti.engine.form.FormProperty;

import org.activiti.explorer.Messages;

import org.activiti.explorer.ui.form.AbstractFormPropertyRenderer;

import org.activiti.engine.impl.form.CollectionFormType;

import com.vaadin.event.ItemClickEvent;

import com.vaadin.ui.AbstractSelect.MultiSelectMode;

import com.vaadin.ui.Field;

import com.vaadin.ui.Table;

public class CollectionFormPropertyRenderer<T> extends

        AbstractFormPropertyRenderer {

    private Table table;

    private Map<String, T> values;

    public CollectionFormPropertyRenderer() {

        super(CollectionFormType.class);

    }

    @Override

    @SuppressWarnings("unchecked")

    public Field getPropertyField(FormProperty formProperty) {

        table = new Table();

        table.setCaption(getPropertyLabel(formProperty));

        table.setRequired(formProperty.isRequired());

        table.setRequiredError(getMessage(Messages.FORM_FIELD_REQUIRED,

                getPropertyLabel(formProperty)));

        table.setEnabled(formProperty.isReadable());

        table.setSelectable(formProperty.isWritable());

        table.setMultiSelect(true);

        table.setMultiSelectMode(MultiSelectMode.SIMPLE);

        table.addListener(new ItemClickEvent.ItemClickListener() {

            private static final long serialVersionUID = -6477528416002075564L;

            @Override

            public void itemClick(ItemClickEvent event) {

                //table.setCaption("CLICCCKATO!!!");

            }

        });

        values = (Map<String, T>) formProperty.getType().getInformation(

                "values");

        Class<T> genericClass = (Class<T>) values.values().iterator().next()

                .getClass();

        Method[] methods = genericClass.getMethods();

        java.lang.reflect.Field[] fields = genericClass.getDeclaredFields();

        for (java.lang.reflect.Field field : fields)

            if (hasMethod(methods, field))

                table.addContainerProperty(field.getName(), String.class, null);

        if (values != null) {

            for (Map.Entry<String, T> enumEntry : values.entrySet()) {

                String id = enumEntry.getKey();

                T value = enumEntry.getValue();

                table.addItem(getValues(fields, methods, value), id);

                if (enumEntry.getValue() != null) {

                    // table.setItemCaption(enumEntry.getKey(),

                    // enumEntry.getValue());

                }

            }

        }

        return table;

    }

    @Override

    public String getFieldValue(FormProperty formProperty, Field field) {

        assert field == table;

        @SuppressWarnings("unchecked")

        Collection<String> ids = (Collection<String>) field.getValue();

        String ret = "";

        for (String id : ids) {

            ret += id + "|";

        }

        return ret;

    }

    private boolean hasMethod(Method[] methods, java.lang.reflect.Field field) {

        for (Method method : methods) {

            String methodName = method.getName();

            if (methodName.startsWith("get")

                    && methodName.substring(3)

                            .equalsIgnoreCase(field.getName()))

                return true;

        }

        return false;

    }

    private Object[] getValues(java.lang.reflect.Field[] fields,

            Method[] methods, T type) {

        List<Object> result = new ArrayList<Object>();

        try {

            for (java.lang.reflect.Field field : fields)

                for (Method method : methods) {

                    String methodName = method.getName();

                    if (methodName.startsWith("get")

                            && methodName.substring(3).equalsIgnoreCase(

                                    field.getName()))

                        result.add(method.invoke(type));

                }

        } catch (UnsupportedOperationException e) {

            e.printStackTrace();

        } catch (IllegalArgumentException e) {

            e.printStackTrace();

        } catch (IllegalAccessException e) {

            e.printStackTrace();

        } catch (InvocationTargetException e) {

            e.printStackTrace();

        }

        return result.toArray();

    }

}