/**
* 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.aurora.common.args;
import java.lang.annotation.Annotation;
import java.lang.reflect.Field;
import java.util.Arrays;
import java.util.List;
import java.util.regex.Pattern;
import javax.annotation.Nullable;
import com.google.common.base.Optional;
import com.google.common.base.Preconditions;
import com.google.common.reflect.TypeToken;
import org.apache.aurora.common.args.apt.Configuration;
import static com.google.common.base.Preconditions.checkArgument;
/**
* Description of a command line option/flag such as -foo=bar.
*/
public final class OptionInfo<T> extends ArgumentInfo<T> {
static final String ARG_NAME_RE = "[\\w\\-\\.]+";
static final String ARG_FILE_HELP_TEMPLATE
= "%s This argument supports @argfile format. See details below.";
private static final Pattern ARG_NAME_PATTERN = Pattern.compile(ARG_NAME_RE);
private static final String NEGATE_BOOLEAN = "no_";
/**
* Factory method to create a OptionInfo from a field.
*
* @param field The field must contain a {@link Arg}.
* @return an OptionInfo describing the field.
*/
static OptionInfo<?> createFromField(Field field) {
return createFromField(field, null);
}
/**
* Factory method to create a OptionInfo from a field.
*
* @param field The field must contain a {@link Arg}.
* @param instance The object containing the non-static Arg instance or else null if the Arg
* field is static.
* @return an OptionInfo describing the field.
*/
static OptionInfo<?> createFromField(final Field field, @Nullable Object instance) {
CmdLine cmdLine = field.getAnnotation(CmdLine.class);
if (cmdLine == null) {
throw new Configuration.ConfigurationException(
"No @CmdLine Arg annotation for field " + field);
}
String name = cmdLine.name();
Preconditions.checkNotNull(name);
checkArgument(!HELP_ARGS.contains(name),
String.format("Argument name '%s' is reserved for builtin argument help", name));
checkArgument(ARG_NAME_PATTERN.matcher(name).matches(),
String.format("Argument name '%s' does not match required pattern %s",
name, ARG_NAME_RE));
@SuppressWarnings({"unchecked", "rawtypes"}) // we have no way to know the type here
OptionInfo<?> optionInfo = new OptionInfo(
name,
getCmdLineHelp(cmdLine),
cmdLine.argFile(),
getArgForField(field, Optional.fromNullable(instance)),
TypeUtil.getTypeParamTypeToken(field),
Arrays.asList(field.getAnnotations()),
cmdLine.parser());
return optionInfo;
}
private static String getCmdLineHelp(CmdLine cmdLine) {
String help = cmdLine.help();
if (cmdLine.argFile()) {
help = String.format(ARG_FILE_HELP_TEMPLATE, help, cmdLine.name(), cmdLine.name());
}
return help;
}
private OptionInfo(
String name,
String help,
boolean argFile,
Arg<T> arg,
TypeToken<T> type,
List<Annotation> verifierAnnotations,
@Nullable Class<? extends Parser<T>> parser) {
super(name, help, arg, type, verifierAnnotations, parser);
}
/**
* Parses the value and store result in the {@link Arg} contained in this {@code OptionInfo}.
*/
void load(ParserOracle parserOracle, String optionName, String value) {
Parser<? extends T> parser = getParser(parserOracle);
Object result = parser.parse(parserOracle, getType().getType(), value); // [A]
// If the arg type is boolean, check if the command line uses the negated boolean form.
if (isBoolean()) {
if (optionName.equals(getNegatedName())) {
result = !(Boolean) result; // [B]
}
}
// We know result is T at line [A] but throw this type information away to allow negation if T
// is Boolean at line [B]
@SuppressWarnings("unchecked")
T parsed = (T) result;
setValue(parsed);
}
boolean isBoolean() {
return getType().getRawType() == Boolean.class;
}
/**
* Similar to the simple name, but with boolean arguments appends "no_", as in:
* {@code -no_fire=false}
*/
String getNegatedName() {
return NEGATE_BOOLEAN + getName();
}
}