DefaultCommandBuilder (unix4j 0.4 API)

java.lang.Object
- org.unix4j.builder.DefaultCommandBuilder

All Implemented Interfaces:

CommandBuilder, To

Direct Known Subclasses:

DefaultUnix4jCommandBuilder
```
public class DefaultCommandBuilder
extends Object
implements CommandBuilder
```
Default implementation for a CommandBuilder. Builds a NoOp command if no command is joined to the command chain of this builder.

Constructor Summary

Constructors
Constructor and Description
`DefaultCommandBuilder()` Default constructor initialized to build a `NoOp` command if no command is `joined` to this builder's command chain.
`DefaultCommandBuilder(ExecutionContextFactory contextFactory)` Constructor using the specified factory to create contexts for command execution.

Method Summary

Methods
Modifier and Type	Method and Description
`CommandBuilder`	`apply(LineOperation operation)` Adds a new command based on the specified operation and adds it to the chain of commands held by this builder.
`Command<?>`	`build()` Builds the composite command and returns it.
`ExecutionContextFactory`	`getContextFactory()` Returns the context factory used to create contexts for command execution.
`CommandBuilder`	`join(Command<?> command)` Adds the specified command to the chain of commands held by this builder.
`CommandBuilder`	`reset()` Resets this command builder to its initial state.
`void`	`toDevNull()` Executes the composite command and does not write the result anywhere.
`int`	`toExitValue()` Executes the composite command returns its exit value, 0 if the command completes successfully and another command specific error value different from zero if the command throws an `ExitValueException`.
`void`	`toFile(File file)` Executes the composite command and writes the result to the given file.
`void`	`toFile(String file)` Executes the composite command and writes the result to the given file.
`List<Line>`	`toLineList()` Executes the composite command and returns the result as a list containing the output lines.
`void`	`toOutput(Output output)` Executes the composite command and writes the result to the given output.
`void`	`toOutputStream(OutputStream stream)` Executes the composite command and writes the result to the given stream.
`void`	`toStdOut()` Executes the composite command and writes the result to the standard output.
`String`	`toString()` Returns a string representation of the composite command that would be returned by `CommandBuilder.build()`.
`List<String>`	`toStringList()` Executes the composite command and returns the result as a list containing the output lines without line ending.
`String`	`toStringResult()` Executes the composite command and returns the result as string.
`void`	`toWriter(Writer writer)` Executes the composite command and writes the result using the given writer.

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

- Constructor Detail
  - DefaultCommandBuilder
```
public DefaultCommandBuilder()
```
    Default constructor initialized to build a NoOp command if no command is joined to this builder's command chain. Uses a DefaultExecutionContext to execute commands.
  - DefaultCommandBuilder
```
public DefaultCommandBuilder(ExecutionContextFactory contextFactory)
```
    Constructor using the specified factory to create contexts for command execution. The builder is initialized with a NoOp command which will be replaced by the first command joined to this builder's command chain.
    
    Parameters:
    contextFactory - the factory used to create execution contexts that are passed to the execute method when a command is executed
- Method Detail
  - getContextFactory
```
public ExecutionContextFactory getContextFactory()
```
    Returns the context factory used to create contexts for command execution. The returned factory has usually been passed to the constructor of this builder.
    
    Returns:
    the factory used to create execution contexts that are passed to the execute method when a command is executed
  - join
```
public CommandBuilder join(Command<?> command)
```
    Description copied from interface: CommandBuilder
    
    Adds the specified command to the chain of commands held by this builder. Application code rarely needs to call this method directly; the command specific methods are usually called instead to join an instance of a certain command, e.g. one of the grep(..) methods to join a grep command.
    If this is the fist joined command, the builder builds this command and returns or executes it if CommandBuilder.build() or toXXX(..) is called, respectively. If the command argument joins already existing commands, the last command in the chain redirects its output to the standard input of the specified command.
    
    Specified by:
    
    join in interface CommandBuilder
    
    Parameters:
    command - the command to join the last previously joined command
    
    Returns:
    the builder for chained method invocation to join other commands
  - apply
```
public CommandBuilder apply(LineOperation operation)
```
    Description copied from interface: CommandBuilder
    
    Adds a new command based on the specified operation and adds it to the chain of commands held by this builder.
    If this is the fist joined command, the builder builds the command created from the operation and returns or executes it if CommandBuilder.build() or toXXX(..) is called, respectively. If the command argument joins already existing commands, the last command in the chain redirects its output to the standard input of the specified command.
    
    Specified by:
    
    apply in interface CommandBuilder
    
    Parameters:
    operation - the operation on which the added command is based
    
    Returns:
    the builder for chained method invocation to join other commands
  - reset
```
public CommandBuilder reset()
```
    Description copied from interface: CommandBuilder
    
    Resets this command builder to its initial state. All joined commands are removed from the command chain leaving the builder in a state to build a NoOp command. New commands can be joined subsequently to create a new command chain.
    
    Specified by:
    
    reset in interface CommandBuilder
    
    Returns:
    the builder for chained method invocation for instance to join the first new command
  - build
```
public Command<?> build()
```
    Description copied from interface: CommandBuilder
    
    Builds the composite command and returns it. The returned command contains a join of all the commands that have been joined up by invoking command specific methods of this builder.
    This method is rarely used by application code. Usually one of the toXXX(..) methods is invoked to execute the command and return the output directly. To get a string representation of the built command, the command's toString() method can be used.
    
    Specified by:
    
    build in interface CommandBuilder
    
    Returns:
    a newly created composite command based on the commands joined up by invoking command specific methods of this builder
  - toString
```
public String toString()
```
    Description copied from interface: CommandBuilder
    Returns a string representation of the composite command that would be returned by CommandBuilder.build(). A composite command string looks for instance like this:
```
 "echo -messages [Hello WORLD] | grep -matchString world -ignoreCase"
 
```
    Use To.toStringResult() instead to execute the command and return the output as a string.
    Specified by:
    
    toString in interface CommandBuilder
    
    Overrides:
    
    toString in class Object
    
    Returns:
    the composite command string with joined commands including arguments and options
  - toStdOut
```
public void toStdOut()
```
    Description copied from interface: To
    
    Executes the composite command and writes the result to the standard output.
    
    Specified by:
    
    toStdOut in interface To
  - toLineList
```
public List<Line> toLineList()
```
    Description copied from interface: To
    
    Executes the composite command and returns the result as a list containing the output lines.
    
    Specified by:
    
    toLineList in interface To
    
    Returns:
    the result as a list of line strings
  - toStringList
```
public List<String> toStringList()
```
    Description copied from interface: To
    
    Executes the composite command and returns the result as a list containing the output lines without line ending.
    
    Specified by:
    
    toStringList in interface To
    
    Returns:
    the result as a list of line strings
  - toOutput
```
public void toOutput(Output output)
```
    Description copied from interface: To
    
    Executes the composite command and writes the result to the given output.
    
    Specified by:
    
    toOutput in interface To
  - toFile
```
public void toFile(String file)
```
    Description copied from interface: To
    
    Executes the composite command and writes the result to the given file.
    
    Specified by:
    
    toFile in interface To
    
    Parameters:
    file - the target output file
  - toFile
```
public void toFile(File file)
```
    Description copied from interface: To
    
    Executes the composite command and writes the result to the given file.
    
    Specified by:
    
    toFile in interface To
    
    Parameters:
    file - the target output file
  - toOutputStream
```
public void toOutputStream(OutputStream stream)
```
    Description copied from interface: To
    
    Executes the composite command and writes the result to the given stream.
    
    Specified by:
    
    toOutputStream in interface To
    
    Parameters:
    stream - the target output stream
  - toWriter
```
public void toWriter(Writer writer)
```
    Description copied from interface: To
    
    Executes the composite command and writes the result using the given writer.
    
    Specified by:
    
    toWriter in interface To
    
    Parameters:
    writer - the writer used to write the output
  - toDevNull
```
public void toDevNull()
```
    Description copied from interface: To
    
    Executes the composite command and does not write the result anywhere.
    
    Specified by:
    
    toDevNull in interface To
  - toStringResult
```
public String toStringResult()
```
    Description copied from interface: To
    
    Executes the composite command and returns the result as string. Line ending characters are inserted between lines if the result contains multiple lines. Note that the last line is NOT terminated with a line ending.
    To return a representation of the command with its arguments without executing the command, toString() can be used instead.
    
    Specified by:
    
    toStringResult in interface To
    
    Returns:
    the result as a string, possibly a multiline string with newline characters between the lines but not after the last line
  - toExitValue
```
public int toExitValue()
```
    Description copied from interface: To
    
    Executes the composite command returns its exit value, 0 if the command completes successfully and another command specific error value different from zero if the command throws an ExitValueException.
    
    Specified by:
    
    toExitValue in interface To
    
    Returns:
    the exit value returned by the command, 0 for success

Class DefaultCommandBuilder

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

DefaultCommandBuilder

DefaultCommandBuilder

Method Detail

getContextFactory

join

apply

reset

build

toString

toStdOut

toLineList

toStringList

toOutput

toFile

toFile

toOutputStream

toWriter

toDevNull

toStringResult

toExitValue