![[OPUS]](opus.gif)
This class is available for the OPUS Blackboard API. The initial OPUS 2.0 release is described here
Constructors:
| File_entry( ) | |
| ~File_entry( ) |
Methods:
| clone( ) | returns a copy of this object |
| str( ) | overrides the base class implementation to format the output as a file name |
| operator==( ) | overrides the base class implementation, adding wildcard support |
| assign( ) | parses file names into fields |
| contains_wildcard( ) | checks the File_entry for wildcards |
Data Members:
static const char FILE_ACTION_INDICATOR; // FILE_ACTION indicator
static const std::string FILE_NAME_TOKEN; // substitution token for
// FILE_ACTION commands
static const std::string IGNORE; // signals FILE_ACTION command
// return status is ignored
static const char DIFF_WILDCARD; // field apply-differences
// wildcard character
static const Field::PAD FILES_PADC; // field pad character
static const int DIRECTORY_IDENT; // unique field ID's
static const int ROOTNAME_IDENT;
static const int EXTENSION_IDENT;
static const int DANGLE_IDENT;
Description
File_entries are abstractions of files in the file system, itself abstracted as the files blackboard. They contain the following fields: Directory, Rootname, Extension, and Dangle. For example, the file specification below is parsed to produce the indicated fields in a File_entry object:
/home/opus/data/lz_1234567890.pod_done
^ ^^ ^^ ^^ ^
| || || || |
--------------------------------------
| | | |
| | | |
Directory Rootname | Dangle
Extension
OPUS file polling applications (which poll the files blackboard)
have the option of specifying a command (a FILE_ACTION) to be
executed once a file event completes normally. The action
is triggered when one of the event File_entry fields is updated
with the status "FILE_SUCCESS" in a call to Opus_env::close_event.
At this point, the indicated command is executed and errors are
reported to the process log file (if requested).
Derived from
Example
#include <iostream>
#include <vector>
#include "files_bb.h"
#include "entry.h"
#include "file_entry.h"
using namespace std;
// The following example uses the Files Blackboard to search for
// a wildcarded file name.
int main(int argc, char* argv[])
{
Files_bb fbb;
File_entry* f_ent = new File_entry("temp.*"); // create File_entry
// file mask
vector<Entry*> results; // results vector
if (fbb.search(f_ent, results)) { // files located
for (int i = 0; i < results.size(); i++) {
cout << "Found file " << f_ent->str() << endl;
delete results[i]; // delete result entry
}
} else {
cout << "No files matching " << f_ent->str()
<< " found." << endl;
}
delete f_ent; // delete mask
return(0);
}
See Also:
File_entry::File_entry - The File_entry constructor.
Synopsis
File_entry::File_entry()
File_entry::File_entry(
const string& fname) // I - file name to assign from
File_entry::File_entry(
const char* fname) // I - file name to assign from
File_entry::File_entry(
const File_entry& e) // I - File_entry to
// initialize from
Description
The constructor creates each of the Field objects (Directory, Rootname, Extension, and Dangle), and if a file name argument is supplied, assigns it to the object. The indicated file need not exist (nor will it be created by this method) on the file system.
Exceptions Thrown
| Bad_val<string> | - if the string does not appear to be a directory specification or invalid characters are present; Bad_val.arg contains the calling argument |
| Io_error<int> | - if a problem occurs determining the current working directory; Io_error.arg contains the value of errno |
| Bad_val<string> | - if the string contains invalid characters; Bad_val.arg contains the calling argument |
| Bad_val<string> | - if the extension prefix is not present or invalid characters are present; Bad_val.arg contains the calling argument |
| Bad_val<string> | - if dangle prefix is not present or invalid characters are present; Bad_val.arg contains the calling argument |
Example
File_entry* new_file = new File_entry("temp.txt");
File_entry::~File_entry - The File_entry destructor.
Synopsis
File_entry::~File_entry()
Description
This method destroys the object.
Exceptions Thrown
File_entry::clone - Create a copy of this object.
Synopsis
Entry* File_entry::clone() const
Description
A new File_entry object is created off the heap and initialized with the contents of this object, then returned to the caller. The client should delete the new object when it is no longer needed.
Returns
A pointer to the new File_entry object initialized with this object.
Exceptions Thrown
File_entry::str - Get the file name stored in the object.
Synopsis
string File_entry::str() const
Description
The base class implementation is overridden by this method in order to remove the padding from each of the fields prior to concatenation.
Returns
string containing the full file specification
Exceptions Thrown
Example
Files_bb fbb;
File_entry* cond = new File_entry("*.log"); // create search mask
cout << "Search on " << cond->str() << " found:" << endl;
vector<Entry*> res;
if (fbb.search(cond, res)) {
for (int i = 0; i < res.size(); i++) {
cout << res[i]->str() << endl; // output file names
delete res[i]; // delete result
}
} else {
cout << "[no files found]" << endl;
}
delete cond; // delete condition
File_entry::assign - Parse file name and assign to each of the object's fields.
Synopsis
void File_entry::assign(
const string& fname) // I - file name to parse
Description
This method parses the input file name into Directory, Rootname, Extension, and Dangle fields. If the path is not absolute, the file name is resolved in terms of the current working directory absolute path.
Exceptions Thrown
| Bad_val<string> | - if the string does not appear to be a directory specification or invalid characters are present; Bad_val.arg contains the calling argument |
| Io_error<int> | - if a problem occurs determining the current working directory; Io_error.arg contains the value of errno |
| Bad_val<string> | - if the string contains invalid characters; Bad_val.arg contains the calling argument |
| Bad_val<string> | - if the extension prefix is not present or invalid characters are present; Bad_val.arg contains the calling argument |
| Bad_val<string> | - if dangle prefix is not present or invalid characters are present; Bad_val.arg contains the calling argument |
Example
File_entry file_ent;
file_ent.assign("/home/opus/process.log");
File_entry::operator== - Compare File_entry objects for equality
Synopsis
bool File_entry::operator==(
const Entry* e) // I - object to compare to
const
Description
This method overrides the base class implementation (which simply calls operator== for each field) to support wildcarding of fields. Two File_entry objects are equal if the non-wildcarded portions of each are identical.
*** Note that a pointer to the object with which the comparison is to be made is required, not a reference.
Returns
true - if the File_entry objects are identical
false - if the File_entry objects differ
Exceptions Thrown
| Type<Entry*> | - if the argument is not of type File_entry; Type.arg points to the calling argument |
File_entry::contains_wildcard - Indicate whether the object contains wildcard characters
Synopsis
bool File_entry::contains_wildcard() const
Description
True is returned if the object contains characters in Os_specific::FILE_SINGLE_CHAR_WILDCARD or Os_specific::FILE_MULTI_CHAR_WILDCARD.
Returns
true - if one or more wildcard characters are present;
false - if no wildcard characters are present
Exceptions Thrown
Copyright © 1997-2000 The Association of Universities for
Research in Astronomy, Inc. All Rights Reserved.
For more information, contact opushelp@stsci.edu
Last modified: 25 April 2000