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Utilities.readFile

Reads a specified file and either returns its contents or writes the bytes to the I/O stream.

This method has three variants:

• readFile (Variant 1) reads the specified file and returns its contents. Assumes default encoding.

• readFile (Variant 2) reads the specified file and returns its contents. You can specify a nondefault encoding.

• readFile (Variant 3) reads the specified file and writes its contents to the specified output stream.

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Utilities.readFile

Reads the specified file and returns its contents.

Syntax

public static final String 
readFile(String pathname)

Parameters

pathname

The pathname of the file to read.

Description

The readFile method reads the file indicated by the passed file path, and returns its contents. The path is internally converted by osSafeSpec(). The method assumes that the character of the file are in the default encoding. (The default encoding is set by the Java VM.)

Returns

If successful, the method returns the contents of the file. If unsuccessful, the method returns null.

Throws

IOException

If the method could not read from pathname or write to os. Common reasons for failure include the following:

• The file specified in pathname does not exist.
• The file specified in pathname exists but the caller does not have permission to read from it.

Example

The following example reads and displays the contents of file D:/java/sonnet.txt. The code assumes that the contents of this file are in the default encoding:

String text = Utilities.readFile("D:/java/sonnet.txt");
System.out.println(text);

See Also

osSafeSpec

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Utilities.readFile

Reads the specified file and returns its contents. Specify the encoding of the input file.

Syntax

public static final String 
readFile(String pathname,
         String encoding)
  throws IOException

Parameters

pathname

The pathname of the file to read.

encoding

Specify the encoding of the contents of the file at pathname. Typical encoding values include "UTF-8" or "Latin-1".

Description

The previous variant of readfile assumes that the contents of pathname are in the default encoding (which is set by the Java VM). By contrast, Variant 2 or readfile allows you to specify the encoding.

Returns

If successful, the method returns the contents of the file. If unsuccessful, the method returns null.

Throws

IOException

If the method could not read from pathname or write to os. Common reasons for failure include the following:

• The file specified in pathname does not exist.
• The file specified in pathname exists but the caller does not have permission to read from it.

See Also

osSafeSpec

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Utilities.readFile

Reads the file indicated by the passed file path and writes the bytes to the output stream.

Syntax

public static final boolean 
readFile(String pathname,
         OutputStream os)
  throws IOException

Parameters

pathname

The pathname of the file to read.

os

The output stream to which this method should write the contents of the file.

Description

This readFile method reads the file indicated by the passed pathname, and writes its contents to the specified output stream. The path is internally converted by osSafeSpec().

Returns

Returns true if no error.

Throws

IOException

If the method could not read from pathname or write to os. Common reasons for failure include the following:

• The output stream specified in os is not writable.
• The file specified in pathname does not exist.
• The file specified in pathname exists but the caller does not have permission to read from it.

See Also

osSafeSpec

 

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