/*
* Copyright 2010-2011 Research In Motion Limited.
*
* 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 blackberry.io.file;
import blackberry.core.FunctionSignature;
import blackberry.core.ScriptableFunctionBase;
import blackberry.io.FileConnectionWrapper;
/**
* JavaScript function class - determines if a specified file exists
* @author awong
*
*/
public final class ExistsFunction extends ScriptableFunctionBase {
public static final String NAME = "exists";
/**
* Check whether a given file exists or not
*
* @param args
* args[0]: the complete URL path to the file
*
* @return Return true if the file exists, false otherwise (note: if the path is to a existing directory (not a file), the
* method will still return false)
*/
public Object execute( Object thiz, Object[] args ) throws Exception {
Boolean exists = null;
FileConnectionWrapper fConnWrap = null;
try {
fConnWrap = new FileConnectionWrapper( args[ 0 ].toString() );
exists = new Boolean( fConnWrap.exists() && !fConnWrap.isDirectory() );
} finally {
if( fConnWrap != null ) {
fConnWrap.close();
}
}
return exists;
}
/**
* @see blackberry.core.ScriptableFunctionBase#getFunctionSignatures
*/
protected FunctionSignature[] getFunctionSignatures() {
FunctionSignature fs = new FunctionSignature( 1 );
fs.addParam( String.class, true );
return new FunctionSignature[] { fs };
}
}