PngMetadata (PNGJ 2.0.1 API)

java.lang.Object
- ar.com.hjg.pngj.chunks.PngMetadata

```
public class PngMetadata
extends Object
```
We consider "image metadata" every info inside the image except for the most basic image info (IHDR chunk - ImageInfo class) and the pixels values.
This includes the palette (if present) and all the ancillary chunks
This class provides a wrapper over the collection of chunks of a image (read or to write) and provides some high level methods to access them

Constructor Summary

Constructors
Constructor and Description

PngMetadata(ChunksList chunks)

Constructors
Constructor and Description
`PngMetadata(ChunksList chunks)`

Method Summary

Methods
Modifier and Type	Method and Description
`PngChunkPLTE`	`createPLTEChunk()` Creates a new empty palette chunk, queues it for write and return it to the caller, who should fill its entries
`PngChunkTRNS`	`createTRNSChunk()` Creates a new empty TRNS chunk, queues it for write and return it to the caller, who should fill its entries
`double[]`	`getDpi()` returns -1 if not found or dimension unknown
`PngChunkPLTE`	`getPLTE()` Returns the palette chunk, if present
`PngChunkTIME`	`getTime()` null if not found
`String`	`getTimeAsString()`
`PngChunkTRNS`	`getTRNS()` Returns the TRNS chunk, if present
`String`	`getTxtForKey(String k)` Returns empty if not found, concatenated (with newlines) if multiple! - and trimmed
`List<? extends PngChunkTextVar>`	`getTxtsForKey(String k)` gets all text chunks with a given key
`void`	`queueChunk(PngChunk c)`
`void`	`queueChunk(PngChunk c, boolean lazyOverwrite)` Queues the chunk at the writer
`void`	`setDpi(double x)`
`void`	`setDpi(double x, double y)`
`PngChunkTextVar`	`setText(String k, String val)`
`PngChunkTextVar`	`setText(String k, String val, boolean useLatin1, boolean compress)` Creates a text chunk and queue it.
`PngChunkTIME`	`setTimeNow()`
`PngChunkTIME`	`setTimeNow(int secsAgo)` Creates a time chunk with current time, less secsAgo seconds
`PngChunkTIME`	`setTimeYMDHMS(int yearx, int monx, int dayx, int hourx, int minx, int secx)` Creates a time chunk with diven date-time

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

- Constructor Detail
  - PngMetadata
```
public PngMetadata(ChunksList chunks)
```
- Method Detail
  - queueChunk
```
public void queueChunk(PngChunk c,
              boolean lazyOverwrite)
```
    Queues the chunk at the writer
    lazyOverwrite: if true, checks if there is a queued "equivalent" chunk and if so, overwrites it. However if that not check for already written chunks.
  - queueChunk
```
public void queueChunk(PngChunk c)
```
  - getDpi
```
public double[] getDpi()
```
    returns -1 if not found or dimension unknown
  - setDpi
```
public void setDpi(double x)
```
  - setDpi
```
public void setDpi(double x,
          double y)
```
  - setTimeNow
```
public PngChunkTIME setTimeNow(int secsAgo)
```
    Creates a time chunk with current time, less secsAgo seconds
    
    Returns:
    Returns the created-queued chunk, just in case you want to examine or modify it
  - setTimeNow
```
public PngChunkTIME setTimeNow()
```
  - setTimeYMDHMS
```
public PngChunkTIME setTimeYMDHMS(int yearx,
                         int monx,
                         int dayx,
                         int hourx,
                         int minx,
                         int secx)
```
    Creates a time chunk with diven date-time
    
    Returns:
    Returns the created-queued chunk, just in case you want to examine or modify it
  - getTime
```
public PngChunkTIME getTime()
```
    null if not found
  - getTimeAsString
```
public String getTimeAsString()
```
  - setText
```
public PngChunkTextVar setText(String k,
                      String val,
                      boolean useLatin1,
                      boolean compress)
```
    Creates a text chunk and queue it.
    
    Parameters:
    k - : key (latin1)
    val - (arbitrary, should be latin1 if useLatin1)
    useLatin1 -
    compress -
    
    Returns:
    Returns the created-queued chunks, just in case you want to examine, touch it
  - setText
```
public PngChunkTextVar setText(String k,
                      String val)
```
  - getTxtsForKey
```
public List<? extends PngChunkTextVar> getTxtsForKey(String k)
```
    gets all text chunks with a given key
    returns null if not found
    Warning: this does not check the "lang" key of iTxt
  - getTxtForKey
```
public String getTxtForKey(String k)
```
    Returns empty if not found, concatenated (with newlines) if multiple! - and trimmed
    Use getTxtsForKey() if you don't want this behaviour
  - getPLTE
```
public PngChunkPLTE getPLTE()
```
    Returns the palette chunk, if present
    
    Returns:
    null if not present
  - createPLTEChunk
```
public PngChunkPLTE createPLTEChunk()
```
    Creates a new empty palette chunk, queues it for write and return it to the caller, who should fill its entries
  - getTRNS
```
public PngChunkTRNS getTRNS()
```
    Returns the TRNS chunk, if present
    
    Returns:
    null if not present
  - createTRNSChunk
```
public PngChunkTRNS createTRNSChunk()
```
    Creates a new empty TRNS chunk, queues it for write and return it to the caller, who should fill its entries

Class PngMetadata

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

PngMetadata

Method Detail

queueChunk

queueChunk

getDpi

setDpi

setDpi

setTimeNow

setTimeNow

setTimeYMDHMS

getTime

getTimeAsString

setText

setText

getTxtsForKey

getTxtForKey

getPLTE

createPLTEChunk

getTRNS

createTRNSChunk