SystemOutAndErrSwapper (Grace Framework - 2023.3.0)

org.grails.test.io.SystemOutAndErrSwapper

```
@CompileStatic
class SystemOutAndErrSwapper
extends Object
```
Convenience class to temporarily swap in an output stream for standard error and standard out.

Nested Class Summary

Nested classes
Modifiers	Name	Description
`static class`	`SystemOutAndErrSwapper.TestOutputCapturingPrintStream`

Field Summary

Fields
Modifiers	Name	Description
`protected boolean`	`swapped`
`protected PrintStream`	`swappedInErr`
`protected OutputStream`	`swappedInErrStream`
`protected PrintStream`	`swappedInOut`
`protected OutputStream`	`swappedInOutStream`
`protected PrintStream`	`swappedOutErr`
`protected PrintStream`	`swappedOutOut`

Properties Summary

Properties
Type	Name and description
`boolean`	`echoErr`
`boolean`	`echoOut`

Constructor Summary

Constructors
Constructor and description
`SystemOutAndErrSwapper(boolean echoOut, boolean echoErr)`

Methods Summary

Methods
Type Params	Return Type	Name and description
	`boolean`	`isSwapped()`
	`List<OutputStream>`	`swapIn()` Replaces System.out and System.err with PrintStream's wrapping outStream and errStream
	`List<OutputStream>`	`swapIn(OutputStream outStream, OutputStream errStream)` Replaces System.out and System.err with PrintStream's wrapping outStream and errStream
	`List<OutputStream>`	`swapOut()` Restores System.out and System.err to what they were before swappedIn() was called.

Inherited Methods Summary

Inherited Methods
Methods inherited from class	Name
`class Object`	`equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- Field Detail
  - protected boolean swapped
  - protected PrintStream swappedInErr
  - protected OutputStream swappedInErrStream
  - protected PrintStream swappedInOut
  - protected OutputStream swappedInOutStream
  - protected PrintStream swappedOutErr
  - protected PrintStream swappedOutOut
- Property Detail
  - final boolean echoErr
  - final boolean echoOut
- Constructor Detail
  - SystemOutAndErrSwapper(boolean echoOut, boolean echoErr)
- Method Detail
  - boolean isSwapped()
  - List<OutputStream> swapIn()
    
    Replaces System.out and System.err with PrintStream's wrapping outStream and errStream
    throws:
    IllegalStateException if a swap is already on
    
    Returns:
    [outStream, errStream]
  - List<OutputStream> swapIn(OutputStream outStream, OutputStream errStream)
    
    Replaces System.out and System.err with PrintStream's wrapping outStream and errStream
    throws:
    IllegalStateException if a swap is already on
    
    Returns:
    [outStream, errStream]
  - List<OutputStream> swapOut()
    
    Restores System.out and System.err to what they were before swappedIn() was called.
    throws:
    IllegalStateException if not in a swap
    
    Returns:
    the underlying output streams for the swap ([out, err])