AutoIndentWriter (stringtemplate API)

java.lang.Object
- org.antlr.stringtemplate.AutoIndentWriter

All Implemented Interfaces:

StringTemplateWriter

Direct Known Subclasses:

NoIndentWriter
```
public class AutoIndentWriter
extends java.lang.Object
implements StringTemplateWriter
```
Essentially a char filter that knows how to auto-indent output by maintaining a stack of indent levels. I set a flag upon newline and then next nonwhitespace char resets flag and spits out indention. The indent stack is a stack of strings so we can repeat original indent not just the same number of columns (don't have to worry about tabs vs spaces then). Anchors are char positions (tabs won't work) that indicate where all future wraps should justify to. The wrap position is actually the larger of either the last anchor or the indentation level. This is a filter on a Writer. \n is the proper way to say newline for options and templates. Templates can mix them but use \n for sure and options like wrap="\n". ST will generate the right thing. Override the default (locale) newline by passing in a string to the constructor.

Field Summary

Fields
Modifier and Type	Field and Description
`protected int[]`	`anchors` Stack of integer anchors (char positions in line); avoid Integer creation overhead.
`protected int`	`anchors_sp`
`protected boolean`	`atStartOfLine`
`protected int`	`charPosition` Track char position in the line (later we can think about tabs).
`protected int`	`charPositionOfStartOfExpr`
`protected java.util.List`	`indents` stack of indents; use List as it's much faster than Stack.
`protected int`	`lineWidth`
`protected java.lang.String`	`newline` \n or \r\n?
`protected java.io.Writer`	`out`

Fields inherited from interface org.antlr.stringtemplate.StringTemplateWriter
NO_WRAP

Constructor Summary

Constructors
Constructor and Description

AutoIndentWriter(java.io.Writer out)

AutoIndentWriter(java.io.Writer out, java.lang.String newline)

Constructors
Constructor and Description
`AutoIndentWriter(java.io.Writer out)`
`AutoIndentWriter(java.io.Writer out, java.lang.String newline)`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`int`	`getIndentationWidth()`
`protected java.lang.StringBuffer`	`getIndentString(int spaces)`
`int`	`indent()`
`int`	`indent(int spaces)`
`void`	`popAnchorPoint()`
`java.lang.String`	`popIndentation()`
`void`	`pushAnchorPoint()`
`void`	`pushIndentation(java.lang.String indent)` Push even blank (null) indents as they are like scopes; must be able to pop them back off stack.
`void`	`setLineWidth(int lineWidth)`
`int`	`write(java.lang.String str)` Write out a string literal or attribute expression or expression element.
`int`	`write(java.lang.String str, java.lang.String wrap)` Write out a string literal or attribute expression or expression element.
`int`	`writeSeparator(java.lang.String str)` Write a separator.
`int`	`writeWrapSeparator(java.lang.String wrap)` Because we might need to wrap at a non-atomic string boundary (such as when we wrap in between template applications ]}; wrap>) we need to expose the wrap string writing just like for the separator.

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

- Field Detail
  - indents
```
protected java.util.List indents
```
    stack of indents; use List as it's much faster than Stack. Grows from 0..n-1. List
  - anchors
```
protected int[] anchors
```
    Stack of integer anchors (char positions in line); avoid Integer creation overhead.
  - anchors_sp
```
protected int anchors_sp
```
  - newline
```
protected java.lang.String newline
```
    \n or \r\n?
  - out
```
protected java.io.Writer out
```
  - atStartOfLine
```
protected boolean atStartOfLine
```
  - charPosition
```
protected int charPosition
```
    Track char position in the line (later we can think about tabs). Indexed from 0. We want to keep charPosition <= lineWidth. This is the position we are *about* to write not the position last written to.
  - lineWidth
```
protected int lineWidth
```
  - charPositionOfStartOfExpr
```
protected int charPositionOfStartOfExpr
```
- Constructor Detail
  - AutoIndentWriter
```
public AutoIndentWriter(java.io.Writer out,
                        java.lang.String newline)
```
  - AutoIndentWriter
```
public AutoIndentWriter(java.io.Writer out)
```
- Method Detail
  - setLineWidth
```
public void setLineWidth(int lineWidth)
```
    Specified by:
    
    setLineWidth in interface StringTemplateWriter
  - pushIndentation
```
public void pushIndentation(java.lang.String indent)
```
    Push even blank (null) indents as they are like scopes; must be able to pop them back off stack. To deal with combined anchors and indentation, force indents to include any current anchor point. If current anchor is beyond current indent width, add the difference to the indent to be added. This prevents a check later to deal with anchors when starting new line.
    
    Specified by:
    
    pushIndentation in interface StringTemplateWriter
  - popIndentation
```
public java.lang.String popIndentation()
```
    Specified by:
    
    popIndentation in interface StringTemplateWriter
  - pushAnchorPoint
```
public void pushAnchorPoint()
```
    Specified by:
    
    pushAnchorPoint in interface StringTemplateWriter
  - popAnchorPoint
```
public void popAnchorPoint()
```
    Specified by:
    
    popAnchorPoint in interface StringTemplateWriter
  - getIndentationWidth
```
public int getIndentationWidth()
```
  - write
```
public int write(java.lang.String str)
          throws java.io.IOException
```
    Write out a string literal or attribute expression or expression element.
    
    Specified by:
    
    write in interface StringTemplateWriter
    
    Throws:
    
    java.io.IOException
  - writeSeparator
```
public int writeSeparator(java.lang.String str)
                   throws java.io.IOException
```
    Description copied from interface: StringTemplateWriter
    
    Write a separator. Same as write() except that a \n cannot be inserted before emitting a separator.
    
    Specified by:
    
    writeSeparator in interface StringTemplateWriter
    
    Throws:
    
    java.io.IOException
  - write
```
public int write(java.lang.String str,
                 java.lang.String wrap)
          throws java.io.IOException
```
    Write out a string literal or attribute expression or expression element. If doing line wrap, then check wrap before emitting this str. If at or beyond desired line width then emit a \n and any indentation before spitting out this str.
    
    Specified by:
    
    write in interface StringTemplateWriter
    
    Throws:
    
    java.io.IOException
  - writeWrapSeparator
```
public int writeWrapSeparator(java.lang.String wrap)
                       throws java.io.IOException
```
    Description copied from interface: StringTemplateWriter
    
    Because we might need to wrap at a non-atomic string boundary (such as when we wrap in between template applications ]}; wrap>) we need to expose the wrap string writing just like for the separator.
    
    Specified by:
    
    writeWrapSeparator in interface StringTemplateWriter
    
    Throws:
    
    java.io.IOException
  - indent
```
public int indent()
           throws java.io.IOException
```
    Throws:
    
    java.io.IOException
  - indent
```
public int indent(int spaces)
           throws java.io.IOException
```
    Throws:
    
    java.io.IOException
  - getIndentString
```
protected java.lang.StringBuffer getIndentString(int spaces)
```

Class AutoIndentWriter

Field Summary

Fields inherited from interface org.antlr.stringtemplate.StringTemplateWriter

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

indents

anchors

anchors_sp

newline

out

atStartOfLine

charPosition

lineWidth

charPositionOfStartOfExpr

Constructor Detail

AutoIndentWriter

AutoIndentWriter

Method Detail

setLineWidth

pushIndentation

popIndentation

pushAnchorPoint

popAnchorPoint

getIndentationWidth

write

writeSeparator

write

writeWrapSeparator

indent

indent

getIndentString