de.intarsys.tools.functor.ChainedArgs Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of isrt Show documentation
Show all versions of isrt Show documentation
The basic runtime tools and interfaces for intarsys components.
/*
* Copyright (c) 2007, intarsys consulting GmbH
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* - Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* - Neither the name of intarsys nor the names of its contributors may be used
* to endorse or promote products derived from this software without specific
* prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
package de.intarsys.tools.functor;
import java.util.HashSet;
import java.util.Iterator;
import java.util.NoSuchElementException;
import java.util.Set;
/**
* An {@link IArgs} implementation allowing to concat two {@link IArgs}
* together. Lookup will be performed in "args" first. If nothing is found,
* lookup is done in "fallbackArgs".
*
*/
public class ChainedArgs implements IArgs {
class Binding implements IBinding {
final private IBinding argBinding;
final private IBinding fallbackBinding;
public Binding(IBinding argBinding, IBinding fallbackBinding) {
super();
this.argBinding = argBinding;
this.fallbackBinding = fallbackBinding;
}
@Override
public String getName() {
return argBinding.getName();
}
@Override
public Object getValue() {
Object result = argBinding.getValue();
if (result == null) {
if (!argBinding.isDefined()) {
Object fallbackValue = fallbackBinding.getValue();
if (fallbackValue instanceof IArgs) {
result = Args.create();
argBinding.setValue(result);
} else {
result = fallbackValue;
}
}
}
if (result instanceof IArgs) {
Object fallbackValue = fallbackBinding.getValue();
if (fallbackValue instanceof IArgs) {
// result = new ChainedArgs((IArgs) result,
// (IArgs) fallbackValue);
result = null;
}
}
return result;
}
@Override
public boolean isDefined() {
return argBinding.isDefined() || fallbackBinding.isDefined();
}
@Override
public void setValue(Object value) {
argBinding.setValue(value);
}
}
private IArgs args;
private IArgs fallbackArgs;
/**
* Create new {@link ChainedArgs} where args are always looked
* up first. If lookup fails, fallbackArgs are used.
*
* @param args
* The main {@link IArgs} to use for lookup
* @param fallbackArgs
* The fallback {@link IArgs} for lookup
*/
public ChainedArgs(IArgs args, IArgs fallbackArgs) {
super();
this.args = args;
this.fallbackArgs = fallbackArgs;
}
public IBinding add(Object object) {
return args.add(object);
}
@Override
public Iterator bindings() {
return new Iterator() {
private IBinding current;
private Iterator argsIterator = args.bindings();
private Iterator fallbackIteratorIndexed = fallbackArgs
.bindings();
private Iterator fallbackIteratorNamed = fallbackArgs
.bindings();
@Override
public boolean hasNext() {
if (current != null) {
return true;
}
IBinding currentArg = null;
IBinding currentFallbackArg = null;
if (argsIterator.hasNext()) {
currentArg = argsIterator.next();
}
if (fallbackIteratorIndexed.hasNext()) {
currentFallbackArg = fallbackIteratorIndexed.next();
}
if (currentArg == null && currentFallbackArg != null
&& currentFallbackArg.getName() == null) {
currentArg = args.add(null);
}
if (currentArg != null) {
String name = currentArg.getName();
if (name == null) {
// positional match
if (currentFallbackArg != null) {
current = new Binding(currentArg,
currentFallbackArg);
} else {
current = currentArg;
}
} else {
// associative match
if (fallbackArgs.isDefined(name)) {
current = new Binding(currentArg,
fallbackArgs.declare(name));
} else {
current = currentArg;
}
}
}
while (current == null && fallbackIteratorNamed.hasNext()) {
currentFallbackArg = fallbackIteratorNamed.next();
String name = currentFallbackArg.getName();
if (name == null) {
// visit only named
continue;
} else if (args.isDefined(name)) {
// already visited
continue;
} else {
current = new Binding(args.declare(name),
currentFallbackArg);
}
}
return false;
}
@Override
public IBinding next() {
if (!hasNext()) {
throw new NoSuchElementException();
}
IBinding result = current;
current = null;
return result;
}
@Override
public void remove() {
throw new UnsupportedOperationException();
}
};
}
public void clear() {
args.clear();
}
@Override
public IArgs copy() {
IArgs result = fallbackArgs.copy();
for (String name : args.names()) {
Object value = args.get(name);
if (value instanceof IArgs) {
result.put(name, ((IArgs) value).copy());
} else {
result.put(name, value);
}
}
return result;
}
@Override
public IBinding declare(String name) {
return new Binding(args.declare(name), fallbackArgs.declare(name));
}
/*
* (non-Javadoc)
*
* @see de.intarsys.tools.functor.IArgs#get(int)
*/
public Object get(int index) {
Object result = args.get(index);
if (result == null) {
Object fallbackResult = fallbackArgs.get(index);
if (fallbackResult instanceof IArgs) {
result = Args.create();
args.put(index, result);
} else {
result = fallbackResult;
}
}
if (result instanceof IArgs) {
Object fallbackResult = fallbackArgs.get(index);
if (fallbackResult instanceof IArgs) {
// result = new ChainedArgs((IArgs) result, (IArgs)
// fallbackResult);
result = null;
}
}
return result;
}
/*
* (non-Javadoc)
*
* @see de.intarsys.tools.functor.IArgs#get(int, java.lang.Object)
*/
public Object get(int index, Object defaultValue) {
Object result = get(index);
if (result == null) {
result = defaultValue;
}
return result;
}
/*
* (non-Javadoc)
*
* @see de.intarsys.tools.functor.IArgs#get(java.lang.String)
*/
public Object get(String name) {
Object result = args.get(name);
if (result == null) {
if (!args.isDefined(name)) {
Object fallbackResult = fallbackArgs.get(name);
if (fallbackResult instanceof IArgs) {
result = Args.create();
args.put(name, result);
} else {
result = fallbackResult;
}
}
}
if (result instanceof IArgs) {
Object fallbackResult = fallbackArgs.get(name);
if (fallbackResult instanceof IArgs) {
// result = new ChainedArgs((IArgs) result, (IArgs)
// fallbackResult);
result = null;
}
}
return result;
}
/*
* (non-Javadoc)
*
* @see de.intarsys.tools.functor.IArgs#get(java.lang.String,
* java.lang.Object)
*/
public Object get(String name, Object defaultValue) {
Object result = get(name);
if (result == null) {
result = defaultValue;
}
return result;
}
/**
* The main (primary) {@link IArgs}.
*
* @return The main (primary) {@link IArgs}.
*/
public IArgs getArgs() {
return args;
}
/**
* The fallback (secondary) {@link IArgs};
*
* @return The fallback (secondary) {@link IArgs};
*/
public IArgs getFallbackArgs() {
return fallbackArgs;
}
public boolean isDefined(String name) {
if (args.isDefined(name)) {
return true;
}
return fallbackArgs.isDefined(name);
}
/*
* (non-Javadoc)
*
* @see de.intarsys.tools.functor.IArgs#isIndexed()
*/
public boolean isIndexed() {
return true;
}
/*
* (non-Javadoc)
*
* @see de.intarsys.tools.functor.IArgs#isNamed()
*/
public boolean isNamed() {
return true;
}
/*
* (non-Javadoc)
*
* @see de.intarsys.tools.functor.IArgs#names()
*/
public Set names() {
Set names = new HashSet(args.names());
names.addAll(fallbackArgs.names());
return names;
}
public IBinding put(int index, Object value) {
return args.put(index, value);
}
public IBinding put(String name, Object value) {
return args.put(name, value);
}
public int size() {
return names().size();
}
@Override
public String toString() {
return ArgTools.toString(this, "");
}
@Override
public void undefine(int index) {
}
@Override
public void undefine(String name) {
}
}
© 2015 - 2024 Weber Informatics LLC | Privacy Policy