All Packages  Class Hierarchy  This Package  Previous  Next  Index

Interface org.ohio.iOhioScreen

public interface iOhioScreen
extends iOhio
iOhioScreen encapsulates the host presentation space. The presentation space is a virtual screen which contains all the characters and attributes that would be seen on a traditional emulator screen. This virtual screen is the primary object for text-based interactions with the host. The iOhioScreen provides methods that manipulate text, search the screen, send keystrokes to the host, and work with the cursor.

An iOhioScreen object can be obtained using the GetScreen() method on an instance of iOhioSession.

The raw presentation space data is maintained in a series of planes which can be accessed by various methods within this class. The text plane contains the actual characters in the presentation space. Most of the methods in iOhioScreen class work exclusively with the text plane.

The remaining planes contain the corresponding attributes for each character in the text plane. The color plane contains color characteristics. The field plane contains the field attributes. The extended plane contains the extended field attributes. The color, field, and extended planes are not interpreted by any of the methods in this class.

Once an instance of iOhioScreen has been obtained, an application can register for iOhioScreen events using the addScreenListener() method. iOhioScreen events are sent to registered listeners whenever the virtual screen is changed for any reason, be it host or operator initiated.

See Also:
iOhioSession, iOhioFields, iOhioField

Method Index

 o addScreenListener(iOhioScreenListener)
Registers a listener object for events dispatched by this iOhioScreen object.
 o findString(String, iOhioPosition, int, int, boolean)
Searches the text plane for the target string.
 o getColumns()
Returns the number of columns in the presentation space.
 o getCursor()
Returns the location of the cursor in the presentation space.
 o getData(iOhioPosition, iOhioPosition, int)
Returns data from the Text, Color, Field or Extended plane of the virtual screen.
 o getFields()
Returns the iOhioFields object associated with this presentation space.
 o getOIA()
Returns the iOhioOIA associated with this presentation space.
 o getRows()
Returns the number of rows in the presentation space.
 o getString()
Returns the entire text plane of the presentation space as a string.
 o removeScreenListener(iOhioScreenListener)
Unregisters a listener object for events dispatched by this iOhioScreen object.
 o sendAid(int)
The sendAid method sends an "aid" keystroke to the virtual screen.
 o sendKeys(String, iOhioPosition)
The sendKeys method sends a string of keys to the virtual screen.
 o setCursor(iOhioPosition)
Sets the location of the cursor in the presentation space.
 o setString(String, iOhioPosition)
The setString method sends a string to the virtual screen at the specified location.

Methods

 o getCursor
 public abstract iOhioPosition getCursor()
Returns the location of the cursor in the presentation space. The row and column of the cursor is contained within the iOhioPosition object.

Returns:
The cursor location.
 o setCursor
 public abstract void setCursor(iOhioPosition cursorPos)
Sets the location of the cursor in the presentation space. The iOhioPosition object provided as input contains the target row and column position for the cursor.

Parameters:
cursorPos - The new cursor position
 o getOIA
 public abstract iOhioOIA getOIA()
Returns the iOhioOIA associated with this presentation space. This object can be used to query the status of the operator information area.

Returns:
The iOhioOIA object for this presentation space.
See Also:
iOhioOIA
 o getFields
 public abstract iOhioFields getFields()
Returns the iOhioFields object associated with this presentation space. This provides another convenient way to access the data in the virtual screen. The iOhioFields object contains a snapshot of all the fields in the current virtual screen. Fields provide convenient methods for interpreting the data in the non-text planes. Zero length fields (due to adjacent field attributes) are not returned in the iOhioFields collection. For unformatted screens, the returned collection contains only one iOhioField that contains the whole presentation space.

Returns:
The iOhioFields object for this presentation space.
See Also:
iOhioFields
 o getRows
 public abstract int getRows()
Returns the number of rows in the presentation space.

Returns:
The number of rows.
 o getColumns
 public abstract int getColumns()
Returns the number of columns in the presentation space.

Returns:
The number of columns.
 o getString
 public abstract String getString()
Returns the entire text plane of the presentation space as a string. All null characters and Field Attribute characters are returned as blank space characters.

Returns:
The entire text plane as a string
 o getData
 public abstract char[] getData(iOhioPosition start,
                                iOhioPosition end,
                                int plane)
Returns data from the Text, Color, Field or Extended plane of the virtual screen.

Parameters:
start - The row and column where to start the search. The position is inclusive (for example, row 1, col 1 means that position 1,1 will be used as the starting location and 1,1 will be included in the data). "start" must be positionally less than "end".
end - The row and column where to end the search. The position is inclusive (for example, row 1, col 1 means that position 1,1 will be used as the ending location and 1,1 will be included in the data). "end" must be positionally greater than "start".
plane - A valid OHIO_PLANE value that indicates:

Constant Value Description
OHIO_PLANE_TEXT 1 Extract data from text plane. OHIO_PLANE_TEXT returns null characters and Field Attribute characters as nulls (OPEN ISSUE>.
OHIO_PLANE_COLOR 2 Extract data from color plane
OHIO_PLANE_FIELD 4 Extract data from field plane
OHIO_PLANE_EXTENDED 8 Extract data from extended plane

Returns:
A character array containing the data that was extracted from the target plane.
See Also:
OHIO_PLANE_TEXT, OHIO_PLANE_COLOR, OHIO_PLANE_FIELD, OHIO_PLANE_EXTENDED
 o findString
 public abstract iOhioPosition findString(String targetString,
                                          iOhioPosition start,
                                          int length,
                                          int dir,
                                          boolean ignoreCase)
Searches the text plane for the target string. Null characters in the text plane are treated as blank spaces during search processing.

Parameters:
targetString - The target string.
startPos - The row and column where to start the search. The position is inclusive (for example, row 1, col 1 means that position 1,1 will be used as the starting location and 1,1 will be included in the search).
length - The length from startPos to include in the search.
dir - An OHIO_DIRECTION value:

Constant Value Description
OHIO_DIRECTION_FORWARD 0 Forward (beginning towards end)
OHIO_DIRECTION_BACKWARD 1 Backward (end towards beginning)

ignoreCase - Indicates whether the search is case sensitive. True means that case will be ignored. False means the search will be case sensitive.
Returns:
If found, an iOhioPosition object containing the target location. If not found, returns a null. The targetString must be completely contained by the target area for the search to be successful.
 o sendKeys
 public abstract void sendKeys(String text,
                               iOhioPosition location)
The sendKeys method sends a string of keys to the virtual screen. This method acts as if keystrokes were being typed from the keyboard.

The keystrokes will be sent to the location given. If no location is provided, the keystrokes will be sent to the current cursor location.

Parameters:
text - The string of characters to be sent.
location - Where to send the string of characters.
See Also:
sendAid
 o sendAid
 public abstract void sendAid(int aidKey)
The sendAid method sends an "aid" keystroke to the virtual screen. These aid keys can be thought of as special keystrokes, like the Enter key, the Tab key, or the Page Up key. All the valid special key values are contained in the OHIO_AID enumeration:

Parameters:
aidKey - The aid key to send to the virtual screen.
See Also:
sendKeys
 o setString
 public abstract void setString(String text,
                                iOhioPosition location)
The setString method sends a string to the virtual screen at the specified location. The string will overlay only unprotected fields, and any parts of the string which fall over protected fields will be discarded.

Parameters:
text - String to place in the virtual screen.
location - Position where the string should be written.
 o addScreenListener
 public abstract void addScreenListener(iOhioScreenListener listener)
Registers a listener object for events dispatched by this iOhioScreen object. The listener object must implement the iOhioScreenListener interface. iOhioScreen events are generated whenever the virtual screen is changed for whatever reason. The source of the change can be the host or it can be user initiated (for example, sendKeys method call).

Listener objects can be unregistered using the removeScreenListener() method.

Parameters:
listener - iOhioScreenListener object which is notified when iOhioScreen events occur.
See Also:
removeScreenListener
 o removeScreenListener
 public abstract void removeScreenListener(iOhioScreenListener listener)
Unregisters a listener object for events dispatched by this iOhioScreen object.

Listener objects can be registered using the addScreenListener() method.

Parameters:
listener - iOhioScreenListener object which is to be removed from the notification list.
See Also:
addScreenListener

All Packages  Class Hierarchy  This Package  Previous  Next  Index