FileResource

java.lang.Object
- edu.duke.FileResource

```
public class FileResource
extends java.lang.Object
```
The FileResource class represents a file and allows access to its contents a line at a time, using the method lines, or a word at a time, using the method words. These strings can then be iterated over using a for loop.
Example usage:
```
 FileResource fr = new FileResource();
 for (String s : fr.words()) {
     // print or process s
 }
 
```
If each line of the file represents separated data values, because its a CSV file, then the user can get a getCSVParser object to access that data more directly, using one of the getCSVParser methods.
Example CSV usage:
```
 FileResource fr = new FileResource("food.csv");
 for (CSVRecord record : fr.getCSVParser()) {
     // print or process fields in record
     String name = record.get("Name");
     // other processing
 }
 
```
This software is licensed with an Apache 2 license, see http://www.apache.org/licenses/LICENSE-2.0 for details.

Constructor Summary

Constructors
Constructor and Description
`FileResource()` Create a `FileResource` object that opens the file chosen by the user using a file selection dialog box.
`FileResource(boolean writable)` Create a `FileResource` object that opens the file chosen by the user using a file selection dialog box, possibly to write to it.
`FileResource(java.io.File file)` Create a `FileResource` object that opens a file represented by the File object passed as a parameter.
`FileResource(java.io.File file, boolean writable)` Create a `FileResource` object that opens a file represented by the File object passed as a parameter, possibly to write to it.
`FileResource(java.lang.String filename)` Create a `FileResource` object that opens a file whose name is passed as a parameter.
`FileResource(java.lang.String filename, boolean writable)` Create a `FileResource` object that opens a file whose name is passed as a parameter, possibly to write to it.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`java.lang.String`	`asString()` Return entire contents of this opened file as one string.
`java.lang.Iterable<java.lang.String>`	`getCSVHeaders(CSVParser parser)` Allows access to the column names of the header row of a CSV file (the first line in the file) one at a time.
`CSVParser`	`getCSVParser()` Returns a `CSVParser` object to access the contents of an open file.
`CSVParser`	`getCSVParser(boolean withHeader)` Returns a `CSVParser` object to access the contents of an open file, possibly without a header row.
`CSVParser`	`getCSVParser(boolean withHeader, java.lang.String delimiter)` Returns a `CSVParser` object to access the contents of an open file, possibly without a header row and a different data delimiter than a comma.
`java.lang.Iterable<java.lang.String>`	`lines()` Allow access to this opened file one line at a time.
`java.lang.Iterable<java.lang.String>`	`words()` Allow access to this opened file one word at a time, where words are separated by white-space.
`void`	`write(StorageResource list)` Writes a list of strings to the end of this file, one element per line.
`void`	`write(java.lang.String s)` Writes a string to the end of this file.

Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - FileResource
```
public FileResource()
```
    Create a FileResource object that opens the file chosen by the user using a file selection dialog box.
    
    Throws:
    
    exception - if no file is selected by the user
  - FileResource
```
public FileResource(java.io.File file)
```
    Create a FileResource object that opens a file represented by the File object passed as a parameter. Useful, for example, when used in conjunction with the DirectoryResource class.
    
    Parameters:
    
    file - the file to be represented by this resource
    
    Throws:
    
    exception - if the file cannot be accessed
  - FileResource
```
public FileResource(java.lang.String filename)
```
    Create a FileResource object that opens a file whose name is passed as a parameter. The named file should be on the current class path to be found.
    
    Parameters:
    
    filename - the name of the file to be opened
    
    Throws:
    
    exception - if the filename cannot be accessed
  - FileResource
```
public FileResource(boolean writable)
```
    Create a FileResource object that opens the file chosen by the user using a file selection dialog box, possibly to write to it. If the user wants to change the contents of the open file by using the method write to add new strings to it, pass true as the second parameter. Otherwise it is assumed the user will only iterate over the existing contents of the file.
    
    Parameters:
    
    writable - allow changes to this file only if true
    
    Throws:
    
    exception - if no file is selected by the user
  - FileResource
```
public FileResource(java.io.File file,
                    boolean writable)
```
    Create a FileResource object that opens a file represented by the File object passed as a parameter, possibly to write to it. If the user wants to change the contents of the open file by using the method write to add new strings to it, pass true as the second parameter. Otherwise it is assumed the user will only iterate over the existing contents of the file. Useful, for example, when used in conjunction with the DirectoryResource class.
    
    Parameters:
    
    file - the file to be represented by this resource
    
    writable - allow changes to this file only if true
    
    Throws:
    
    exception - if the file cannot be accessed
  - FileResource
```
public FileResource(java.lang.String filename,
                    boolean writable)
```
    Create a FileResource object that opens a file whose name is passed as a parameter, possibly to write to it. If the user wants to change the contents of the open file by using the method write to add new strings to it, pass true as the second parameter. Otherwise it is assumed the user will only iterate over the existing contents of the file. The named file should be on the current class path to be found.
    
    Parameters:
    
    filename - the name of the file to be opened
    
    writable - allow changes to this file only if true
    
    Throws:
    
    exception - if the filename cannot be accessed
- Method Detail
  - lines
```
public java.lang.Iterable<java.lang.String> lines()
```
    Allow access to this opened file one line at a time.
    
    Returns:
    
    an Iterable that will allow access to contents of opened file one line at a time.
  - words
```
public java.lang.Iterable<java.lang.String> words()
```
    Allow access to this opened file one word at a time, where words are separated by white-space. This means any form of spaces, like tabs or newlines, can delimit words.
    
    Returns:
    
    an Iterable that will allow access to contents of opened file one word at a time.
  - asString
```
public java.lang.String asString()
```
    Return entire contents of this opened file as one string.
    
    Returns:
    
    a String that is the contents of the open file
  - getCSVParser
```
public CSVParser getCSVParser()
```
    Returns a CSVParser object to access the contents of an open file. Each line of the file should be formatted as data separated by commas and with a header row to describe the column names.
    
    Returns:
    
    a CSVParser that can provide access to the records in the file one at a time
    
    Throws:
    
    exception - if this file does not represent a CSV formatted data
  - getCSVParser
```
public CSVParser getCSVParser(boolean withHeader)
```
    Returns a CSVParser object to access the contents of an open file, possibly without a header row. Each line of the file should be formatted as data separated by commas and with/without a header row to describe the column names.
    
    Parameters:
    
    withHeader - uses first row of data as a header row only if true
    
    Returns:
    
    a CSVParser that can provide access to the records in the file one at a time
    
    Throws:
    
    exception - if this file does not represent a CSV formatted data
  - getCSVParser
```
public CSVParser getCSVParser(boolean withHeader,
                              java.lang.String delimiter)
```
    Returns a CSVParser object to access the contents of an open file, possibly without a header row and a different data delimiter than a comma. Each line of the file should be formatted as data separated by the delimiter passed as a parameter and with/without a header row to describe the column names. This is useful if the data is separated by some character other than a comma.
    
    Parameters:
    
    withHeader - uses first row of data as a header row only if true
    
    delimiter - a single character that separates one field of data from another
    
    Returns:
    
    a CSVParser that can provide access to the records in the file one at a time
    
    Throws:
    
    exception - if this file does not represent a CSV formatted data
    
    exception - if delimiter.length() != 1
  - getCSVHeaders
```
public java.lang.Iterable<java.lang.String> getCSVHeaders(CSVParser parser)
```
    Allows access to the column names of the header row of a CSV file (the first line in the file) one at a time. If the CSV file did not have a header row, then an empty Iterator is returned.
    
    Parameters:
    
    parser - the CSVParser that has been created for this file
    
    Returns:
    
    an Iterable that allows access one header name at a time
  - write
```
public void write(java.lang.String s)
```
    Writes a string to the end of this file.
    
    Parameters:
    
    s - the string to saved to the file
  - write
```
public void write(StorageResource list)
```
    Writes a list of strings to the end of this file, one element per line.
    
    Parameters:
    
    list - the strings to saved to the file

Class FileResource

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

FileResource

FileResource

FileResource

FileResource

FileResource

FileResource

Method Detail

lines

words

asString

getCSVParser

getCSVParser

getCSVParser

getCSVHeaders

write

write