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org.directwebremoting.convert.BasicObjectConverter Maven / Gradle / Ivy

package org.directwebremoting.convert;

import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.StringTokenizer;
import java.util.TreeMap;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.directwebremoting.ConversionException;
import org.directwebremoting.extend.ConstructorProperty;
import org.directwebremoting.extend.ConvertUtil;
import org.directwebremoting.extend.ConverterManager;
import org.directwebremoting.extend.InboundContext;
import org.directwebremoting.extend.InboundVariable;
import org.directwebremoting.extend.NamedConverter;
import org.directwebremoting.extend.ObjectOutboundVariable;
import org.directwebremoting.extend.OutboundContext;
import org.directwebremoting.extend.OutboundVariable;
import org.directwebremoting.extend.Property;
import org.directwebremoting.extend.ProtocolConstants;
import org.directwebremoting.util.LocalUtil;
import org.directwebremoting.util.Pair;

/**
 * BasicObjectConverter is a parent to {@link BeanConverter} and
 * {@link ObjectConverter} an provides support for include and exclude lists,
 * and instanceTypes.
 * @author Joe Walker [joe at getahead dot ltd dot uk]
 */
public abstract class BasicObjectConverter implements NamedConverter
{
    /* (non-Javadoc)
     * @see org.directwebremoting.Converter#convertInbound(java.lang.Class, org.directwebremoting.InboundVariable, org.directwebremoting.InboundContext)
     */
    public Object convertInbound(Class paramType, InboundVariable data) throws ConversionException
    {
        if (data.isNull())
        {
            return null;
        }

        String value = data.getValue();
        if (value == null)
        {
            throw new NullPointerException(data.toString());
        }

        // If the text is null then the whole bean is null
        if (value.trim().equals(ProtocolConstants.INBOUND_NULL))
        {
            return null;
        }

        if (!value.startsWith(ProtocolConstants.INBOUND_MAP_START) || !value.endsWith(ProtocolConstants.INBOUND_MAP_END))
        {
            log.warn("Expected object while converting data for " + paramType.getName() + " in " + data.getContext().getCurrentProperty() + ". Passed: " + value);
            throw new ConversionException(paramType, "Data conversion error. See logs for more details.");
        }

        value = value.substring(1, value.length() - 1);

        try
        {
            // Loop through the properties passed in
            Map tokens = extractInboundTokens(paramType, value);

            if (paramsString == null)
            {
                return createUsingSetterInjection(paramType, data, tokens);
            }
            else
            {
                return createUsingConstructorInjection(paramType, data, tokens);
            }
        }
        catch (InvocationTargetException ex)
        {
            throw new ConversionException(paramType, ex.getTargetException());
        }
        catch (ConversionException ex)
        {
            throw ex;
        }
        catch (Exception ex)
        {
            throw new ConversionException(paramType, ex);
        }
    }

    /**
     * We're using constructor injection, create and populate a bean using
     * a constructor
     */
    private Object createUsingConstructorInjection(Class paramType, InboundVariable data, Map tokens) throws NoSuchMethodException, InstantiationException, IllegalAccessException, InvocationTargetException
    {
        Class type;
        if (instanceType != null)
        {
            type = instanceType;
        }
        else
        {
            type = paramType;
        }

        // Find a constructor to match
        List> parameterTypes = new ArrayList>();
        for (Pair, String> parameter : parameters)
        {
            parameterTypes.add(parameter.left);
        }
        Class[] paramTypeArray = parameterTypes.toArray(new Class[parameterTypes.size()]);

        Constructor constructor;
        try
        {
            constructor = type.getConstructor(paramTypeArray);
        }
        catch (NoSuchMethodException ex)
        {
            log.error("Can't find a constructor for " + type.getName() + " with params " + parameterTypes);
            throw ex;
        }

        List arguments = new ArrayList();

        int paramNum = 0;
        for (Pair, String> parameter : parameters)
        {
            String argument = tokens.get(parameter.right);
            ConstructorProperty property = new ConstructorProperty(constructor, parameter.right, paramNum);
            Object output = convert(argument, parameter.left, data.getContext(), property);
            arguments.add(output);
            paramNum++;
        }

        // log.debug("Using constructor injection for: " + constructor);

        Object[] argArray = arguments.toArray(new Object[arguments.size()]);

        try
        {
            return constructor.newInstance(argArray);
        }
        catch (InstantiationException ex)
        {
            log.error("Error building using constructor " + constructor.getName() + " with arguments " + argArray);
            throw ex;
        }
        catch (IllegalAccessException ex)
        {
            log.error("Error building using constructor " + constructor.getName() + " with arguments " + argArray);
            throw ex;
        }
        catch (InvocationTargetException ex)
        {
            log.error("Error building using constructor " + constructor.getName() + " with arguments " + argArray);
            throw ex;
        }
    }

    /**
     * We're using setter injection, create and populate a bean using property
     * setters
     */
    private Object createUsingSetterInjection(Class paramType, InboundVariable data, Map tokens) throws InstantiationException, IllegalAccessException, NoSuchMethodException, InvocationTargetException {
        Object bean;
        if (instanceType != null)
        {
            bean = instanceType.getDeclaredConstructor().newInstance();
        }
        else
        {
            bean = createParameterInstance(paramType);
        }

        // We should put the new object into the working map in case it
        // is referenced later nested down in the conversion process.
        if (instanceType != null)
        {
            data.getContext().addConverted(data, instanceType, bean);
        }
        else
        {
            data.getContext().addConverted(data, paramType, bean);
        }

        Map properties = getPropertyMapFromObject(bean, false, true);

        for (Entry entry : tokens.entrySet())
        {
            String key = entry.getKey();

            // TODO: We don't URL decode method names we probably should. This is $dwr
            // TODO: We should probably have stripped these out already
            if (key.startsWith("%24dwr"))
            {
                continue;
            }

            Property property = properties.get(key);
            if (property == null)
            {
                log.warn("Missing setter: " + paramType.getName() + ".set" + Character.toTitleCase(key.charAt(0)) + key.substring(1) + "() to match javascript property: " + key + ". Check include/exclude rules and overloaded methods.");
                continue;
            }

            Object output = convert(entry.getValue(), property.getPropertyType(), data.getContext(), property);
            property.setValue(bean, output);
        }
        return bean;
    }

    /**
     * Extension point for subclasses to instantiate parameter classes.
     *
     * @param paramType The type of parameter that needs to be instantiated
     * @return An instance of paramType
     * @throws InstantiationException ...
     * @throws IllegalAccessException ...
     * @throws InvocationTargetException ...
     * @throws NoSuchMethodException ...
     */
    protected Object createParameterInstance(Class paramType) throws InstantiationException, IllegalAccessException, NoSuchMethodException, InvocationTargetException {
        return paramType.getDeclaredConstructor().newInstance();
    }

    /**
     * We have inbound data and a type that we need to convert it into, this
     * method performs the conversion.
     * @param val ...
     * @param  propType ...
     * @param inboundContext ...
     * @param property ...
     * @return ...
     */
    protected Object convert(String val, Class propType, InboundContext inboundContext, Property property)
    {
        String[] split = ConvertUtil.splitInbound(val);
        String splitValue = split[ConvertUtil.INBOUND_INDEX_VALUE];
        String splitType = split[ConvertUtil.INBOUND_INDEX_TYPE];

        InboundVariable nested = new InboundVariable(inboundContext, null, splitType, splitValue);
        nested.dereference();
        Property incc = createTypeHintContext(inboundContext, property);

        return converterManager.convertInbound(propType, nested, incc);
    }

    /**
     * {@link #convertInbound} needs to create a {@link Property} for the
     * {@link Property} it is converting so that the type guessing system can do
     * its work.
     * 

The method of generating a {@link Property} is different for * the {@link BeanConverter} and the {@link ObjectConverter}. * @param inctx The parent context * @param property The property being converted * @return The new TypeHintContext */ protected abstract Property createTypeHintContext(InboundContext inctx, Property property); /* (non-Javadoc) * @see org.directwebremoting.Converter#convertOutbound(java.lang.Object, org.directwebremoting.OutboundContext) */ public OutboundVariable convertOutbound(Object data, OutboundContext outctx) throws ConversionException { // Where we collect out converted children Map ovs = new TreeMap(); // We need to do this before collecting the children to save recursion ObjectOutboundVariable ov = new ObjectOutboundVariable(outctx, data.getClass(), getJavascript()); outctx.put(data, ov); try { Map properties = getPropertyMapFromObject(data, true, false); for (Entry entry : properties.entrySet()) { String name = entry.getKey(); Property property = entry.getValue(); Object value = property.getValue(data); OutboundVariable nested = getConverterManager().convertOutbound(value, outctx); ovs.put(name, nested); } } catch (ConversionException ex) { throw ex; } catch (Exception ex) { throw new ConversionException(data.getClass(), ex); } ov.setChildren(ovs); return ov; } /** * Set a list of properties excluded from conversion * @param excludes The space or comma separated list of properties to exclude */ public void setExclude(String excludes) { if (inclusions != null) { throw new IllegalArgumentException("Can't have both inclusions and exclusions for a Converter"); } exclusions = new ArrayList(); String toSplit = excludes.replace(",", " "); StringTokenizer st = new StringTokenizer(toSplit); while (st.hasMoreTokens()) { String rule = st.nextToken(); if (rule.startsWith("get")) { log.warn("Exclusions are based on property names and not method names. '" + rule + "' starts with 'get' so it looks like a method name and not a property name."); } exclusions.add(rule); } } /** * Set a list of properties included from conversion * @param includes The space or comma separated list of properties to exclude */ public void setInclude(String includes) { if (exclusions != null) { throw new IllegalArgumentException("Can't have both inclusions and exclusions for a Converter"); } inclusions = new ArrayList(); String toSplit = includes.replace(",", " "); StringTokenizer st = new StringTokenizer(toSplit); while (st.hasMoreTokens()) { String rule = st.nextToken(); if (rule.startsWith("get")) { log.warn("Inclusions are based on property names and not method names. '" + rule + "' starts with 'get' so it looks like a method name and not a property name."); } inclusions.add(rule); } } /** * @param name The class name to use as an implementation of the converted bean * @throws ClassNotFoundException If the given class can not be found */ public void setImplementation(String name) throws ClassNotFoundException { setInstanceType(LocalUtil.classForName(name)); } /** * Check with the access rules to see if we are allowed to convert a property * @param property The property to test * @return true if the property may be marshalled */ protected boolean isAllowedByIncludeExcludeRules(String property) { if (exclusions != null) { // Check each exclusions and return false if we get a match for (String exclusion : exclusions) { if (property.equals(exclusion)) { return false; } } // So we passed all the exclusions. The setters enforce mutual // exclusion between exclusions and inclusions so we don't need to // 'return true' here, we can carry on. This has the advantage that // we can relax the mutual exclusion at some stage. } if (inclusions != null) { // Check each inclusion and return true if we get a match for (String inclusion : inclusions) { if (property.equals(inclusion)) { return true; } } // Since we are white-listing with inclusions and there was not // match, this property is not allowed. return false; } // default to allow if there are no inclusions or exclusions return true; } /** * Loop over all the inputs and extract a Map of key:value pairs * @param paramType The type we are converting to * @param value The input string * @return A Map of the tokens in the string * @throws ConversionException If the marshalling fails */ protected static Map extractInboundTokens(Class paramType, String value) throws ConversionException { Map tokens = new HashMap(); StringTokenizer st = new StringTokenizer(value, ProtocolConstants.INBOUND_MAP_SEPARATOR); int size = st.countTokens(); for (int i = 0; i < size; i++) { String token = st.nextToken(); if (token.trim().length() == 0) { continue; } int colonpos = token.indexOf(ProtocolConstants.INBOUND_MAP_ENTRY); if (colonpos == -1) { throw new ConversionException(paramType, "Missing " + ProtocolConstants.INBOUND_MAP_ENTRY + " in object description: " + token); } String key = token.substring(0, colonpos).trim(); String val = token.substring(colonpos + 1).trim(); tokens.put(key, val); } return tokens; } /* (non-Javadoc) * @see org.directwebremoting.extend.Converter#setConverterManager(org.directwebremoting.extend.ConverterManager) */ public void setConverterManager(ConverterManager converterManager) { this.converterManager = converterManager; } /** * Accessor for the current ConverterManager * @return the current ConverterManager */ public ConverterManager getConverterManager() { return converterManager; } /** * To forward marshalling requests */ protected ConverterManager converterManager = null; /* (non-Javadoc) * @see org.directwebremoting.convert.NamedConverter#getJavascript() */ public String getJavascript() { return javascript; } /* (non-Javadoc) * @see org.directwebremoting.convert.NamedConverter#setJavascript(java.lang.String) */ public void setJavascript(String javascript) { this.javascript = javascript; } /** * The javascript class name for the converted objects */ protected String javascript = null; /* (non-Javadoc) * @see org.directwebremoting.extend.NamedConverter#getJavascriptSuperClass() */ public String getJavascriptSuperClass() { return javascriptSuperClass; } /* (non-Javadoc) * @see org.directwebremoting.extend.NamedConverter#setJavascriptSuperClass(java.lang.String) */ public void setJavascriptSuperClass(String javascriptSuperClass) { this.javascriptSuperClass = javascriptSuperClass; } /** * The javascript class name that will appear as superclass * for the converted objects */ protected String javascriptSuperClass = null; /* (non-Javadoc) * @see org.directwebremoting.convert.NamedConverter#getInstanceType() */ public Class getInstanceType() { return instanceType; } /* (non-Javadoc) * @see org.directwebremoting.convert.NamedConverter#setInstanceType(java.lang.Class) */ public void setInstanceType(Class instanceType) { this.instanceType = instanceType; } /** * A type that allows us to fulfill an interface or subtype requirement */ protected Class instanceType = null; /** * Set the parameters to be used for constructor injection * @param paramsString a comma separated list of type/name pairs. */ public void setConstructor(String paramsString) { this.paramsString = paramsString; // Convert a paramString into a list of parameters StringTokenizer st = new StringTokenizer(paramsString, ","); while (st.hasMoreTokens()) { String paramString = st.nextToken().trim(); String[] paramParts = paramString.split(" "); if (paramParts.length != 2) { log.error("Parameter list includes parameter '" + paramString + "' that can't be parsed into a [type] and [name]"); throw new IllegalArgumentException("Badly formatted constructor parameter list. See log console for details."); } String typeName = paramParts[0]; try { Class type = LocalUtil.classForName(typeName); Pair, String> parameter = new Pair, String>(type, paramParts[1]); parameters.add(parameter); } catch (ClassNotFoundException ex) { if (typeName.contains(".")) { log.error("Parameter list includes unknown type '" + typeName + "'"); throw new IllegalArgumentException("Unknown type in constructor parameter list. See log console for details."); } else { try { Class type = LocalUtil.classForName("java.lang." + typeName); Pair, String> parameter = new Pair, String>(type, paramParts[1]); parameters.add(parameter); } catch (ClassNotFoundException ex2) { log.error("Parameter list includes unknown type '" + typeName + "' (also tried java.lang." + typeName + ")"); throw new IllegalArgumentException("Unknown type in constructor parameter list. See log console for details."); } } } } } /** * Returns an immutable List of the inclusions. * * @return ... */ public List getInclusions() { return Collections.unmodifiableList(this.inclusions); } /** * Stored temporarily until the {@link #instanceType} is known so we can * parse for constructor injection */ protected String paramsString; /** * The constructor to use if we are doing constructor injection */ protected Map, Constructor> constructorCache = new HashMap, Constructor>(); /** * If we are doing constructor injection, this is the type list */ protected final List, String>> parameters = new ArrayList,String>>(); /** * The list of excluded properties */ protected List exclusions = null; /** * The list of included properties */ protected List inclusions = null; /** * The log stream */ private static final Log log = LogFactory.getLog(BasicObjectConverter.class); }