# PDFExplorer Class

The PDFExplorer class provides access to the low-level PDF document structure.

## Syntax

```text
pdfsdk.PDFExplorer
```

## Remarks

The PDFExplorer class can be used to inspect the internals of a PDF document and make changes to the low-level document structure.

### Object Types and Document Structure

The PDF specification defines eight object types:

- Name
- String
- Real
- Integer
- Boolean
- Array
- Dictionary
- Stream

 In PDFExplorer, name, string, real, integer, and boolean objects are categorized as "primitive" objects, and array, dictionary, and stream objects are categorized as "container" objects.

Before accessing individual objects with the class, it is important to understand how they are structured in the document. PDFExplorer aims to distinguish between the logical and physical representations of objects.

The **logical representation** is that a PDF document is a tree of objects that can be traversed to extract data. For example, every document contains a document catalog that references a next-level object */Pages*, which in turn references individual pages via a */Kids* array. So to get a page, you would first look for the */Root* object in the document trailer, then proceed to its */Pages* element, and then work with the */Kids* array.

Then, there is the **physical structure** that consists of all the objects that constitute the document. Every object is recorded as either:

- A direct (in-place) object (e.g., */Numbers [1 2 3 888]*),
- An indirect (numbered) object, or
- A reference to an indirect object (e.g., */Numbers 8 0 R*).

 The way the objects are physically stored is generally independent from their logical structure. If you are looking for a page, it is of little importance whether each object that you need to traverse to reach it is stored in-place, in one of the indirect objects, or in a compressed object stream.

Note that most heavy objects (such as streams and dictionaries) are recorded in PDF files as indirect objects, with other objects referencing them. An indirect object is a global object that is uniquely identified by its object number followed by its generation number (e.g., *1 0 obj*).

### Navigating the Document

 To navigate the object tree, first provide the input document as a file ([InputFile](#inputfile-property-pdfexplorer-class)), byte array ([InputData](#inputdata-property-pdfexplorer-class)), or stream ([SetInputStream](#setinputstream-method-pdfexplorer-class)) and call [Open](#open-method-pdfexplorer-class). This method populates the [RootObjects](#rootobjects-property-pdfexplorer-class) collection with the existing objects in the document trailer, as the trailer is considered to be the root of the logical object tree. The keys in the document trailer are typically */Size*, */Info*, */Root*, */ID*, and */Encrypt* for encrypted documents.

These objects can then be used as a starting point for the document tree navigation, which is done using [Select](#select-method-pdfexplorer-class). This method and others operate the following syntax for specifying objects in the document:

- Slashes separate levels of hierarchy, like in file paths.
- The "root" slash (*/*) points to the document trailer dictionary.
- A path that does not start with a slash specifies an indirect object in the list of global numbered objects.
- The asterisk character (***) specifies all objects at the provided path.

 **Examples:**

Consider the following PDF document:

```text
%PDF-1.4
%cmmt
1 0 obj
<< /Type /Catalog
/Pages 2 0 R
>>
endobj

2 0 obj
<< /Type /Pages
/Kids [ 3 0 R ]
/Count 1
>>
endobj

3 0 obj
<< /Type /Page
/Parent 2 0 R
/MediaBox [ 0  0  612  792 ]
/Resources << /ProcSet 4 0 R >>
>>
endobj

4 0 obj
[ /PDF ]
endobj

xref
0 5
0000000000 65535 f
0000000015 00000 n
0000000065 00000 n
0000000125 00000 n
0000000234 00000 n
trailer
<< /Size 5
/Root 1 0 R
>>
startxref
259
%%EOF
```

[Select](#select-method-pdfexplorer-class) would return the following results for the respective paths:

- */* - a dictionary object that corresponds to the *trailer* dictionary.
- */Root* - a dictionary object that corresponds to the dictionary at *1 0 obj*, with its [Disposition](#PDFObject_f_Disposition) set to *podReference* (as this is a reference to an indirect object).
- */Size* - an integer object whose [Value](#PDFObject_f_Value) is *5* and [Disposition](#PDFObject_f_Disposition) is *podDirect* (as this is a direct, in-place object).
- */Root/Type* - a name object whose [Value](#PDFObject_f_Value) is *Catalog* ([Disposition](#PDFObject_f_Disposition) = *podDirect*).
- */Root/Pages* - a dictionary object that corresponds to the dictionary at *2 0 obj* ([Disposition](#PDFObject_f_Disposition) = *podReference*).
- */Root/Pages/Kids* - an array object ([Disposition](#PDFObject_f_Disposition) = *podDirect*).
- */Root/Pages/Kids[0]* - a dictionary object that corresponds to the dictionary at *3 0 obj* ([Disposition](#PDFObject_f_Disposition) = *podReference*).
- */Root/Pages/Kids[0]/MediaBox* - an array object with four integer elements ([Disposition](#PDFObject_f_Disposition) = *podDirect*).
- */Root/Pages/Kids[0]/MediaBox[2]* - an integer object whose [Value](#PDFObject_f_Value) is *612* ([Disposition](#PDFObject_f_Disposition) = *podDirect*).
- *3 0 obj* - a dictionary object that corresponds to the dictionary at *3 0 obj* ([Disposition](#PDFObject_f_Disposition) = *podIndirect*).
- *3 0 obj/Type* - a name object whose [Value](#PDFObject_f_Value) is *Page* ([Disposition](#PDFObject_f_Disposition) = *podDirect*).
- *3 0 obj/Parent* - a dictionary object that corresponds to the dictionary at *2 0 obj* ([Disposition](#PDFObject_f_Disposition) = *podReference*).

 Once [Select](#select-method-pdfexplorer-class) returns, the selected object(s) will be available in the [SelectedObjects](#selectedobjects-property-pdfexplorer-class) collection.

### Adding and Modifying Objects

 The below sections contain instructions for adding and modifying each type of object. Note that each of the following *Add** methods returns the path to the newly added object in the document, making it easy to access the [PDFObject](#pdfobject-type) object later using [Select](#select-method-pdfexplorer-class). These objects' values can then be adjusted to ensure the PDF document meets your requirements.

**Primitive Objects**

A primitive object is a non-container object that represents a name, string, real (double), integer, or boolean value. Primitive objects are typically stored in-place and referenced directly. Use the [AddPrimitive](#addprimitive-method-pdfexplorer-class) method to add a direct primitive object and the [AddObject](#addobject-method-pdfexplorer-class) method (passing *true* to the *Indirect* parameter) to add an indirect primitive object:

```csharp
// Adding a direct string object to the /Info dictionary
string stringPath = pdfexplorer.AddPrimitive("/Info", "Creator", "Microsoft Word");

// Adding an indirect boolean object to the root
string booleanPath = pdfexplorer.AddObject("", (int)PDFObjectTypes.potBoolean, "", "true", true);
```

```text
5 0 obj
<<
...
/Creator (Microsoft Word)
>>
endobj

...

6 0 obj
true
endobj
```

The value of a primitive object can then be modified if desired:

```csharp
pdfexplorer.Select(stringPath, true);
pdfexplorer.SelectedObjects[0].Value = "nsoftware.SecurePDF";

pdfexplorer.Select(booleanPath, true);
pdfexplorer.SelectedObjects[0].Value = "false";
```

```text
5 0 obj
<<
...
/Creator (nsoftware.SecurePDF)
>>
endobj

...

6 0 obj
false
endobj
```

**Array and Dictionary Objects**

Unlike primitives, arrays and dictionaries are objects that contain other objects. Elements within array objects are arranged sequentially and have implicit zero-based indices, whereas dictionary objects contain named key-value pairs that are unordered. Use the [AddContainer](#addcontainer-method-pdfexplorer-class) method to add a direct or indirect array or dictionary object:

```csharp
// Adding a direct array object to the first page's /Page dictionary
string arrayPath = pdfexplorer.AddContainer("/Root/Pages/Kids[0]", "CropBox", false, false);

// Adding an indirect dictionary object to the root
string dictPath = pdfexplorer.AddContainer("", "", true, true);
```

```text
3 0 obj
<< /Type /Page
...
/CropBox [
]>>
endobj

...

7 0 obj
<<
>>
endobj
```

An array or dictionary object can then be modified by adding elements to it. The example below populates the */CropBox* array with four integer objects and adds a */Type* key to the newly created dictionary.

```csharp
string cropBox0Path = pdfexplorer.AddPrimitive(arrayPath, "", "0");
string cropBox1Path = pdfexplorer.AddPrimitive(arrayPath, "", "0");
string cropBox2Path = pdfexplorer.AddPrimitive(arrayPath, "", "612");
string cropBox3Path = pdfexplorer.AddPrimitive(arrayPath, "", "792");

string typePath = pdfexplorer.AddPrimitive(dictPath, "Type", "/SampleType");
```

```text
3 0 obj
<< /Type /Page
...
/CropBox [
0
0
612
792
]>>
endobj

...

7 0 obj
<<
/Type /SampleType
>>
endobj
```

**Stream Objects**

A stream object is a compound object consisting of a dictionary and a sequence of bytes. Stream objects are always indirect and are used to store data such as images, fonts, and other resources. Use the [AddStream](#addstream-method-pdfexplorer-class) method to add a stream object:

```csharp
// Adding a stream object to the root
byte[] image1Data = File.ReadAllBytes("image1.png");
string streamPath = pdfexplorer.AddStream("", "", image1Data);
```

```text
8 0 obj
<<
/Length 6317
>>stream
... % binary data for image1.png
endstream
endobj
```

To modify a stream object, use the [SetObjectData](#setobjectdata-method-pdfexplorer-class) or [SetObjectStream](#setobjectstream-method-pdfexplorer-class) method:

```csharp
byte[] image2Data = File.ReadAllBytes("image2.png");
pdfexplorer.SetObjectData(streamPath, image2Data);
// or pdfexplorer.SetObjectStream(streamPath, new MemoryStream(image2Data));
```

```text
8 0 obj
<<
/Length 197
>>stream
... % binary data for image2.png
endstream
endobj
```

**Object References**

An (indirect) object reference is a reference to an indirect object from another object. Its syntax consists of the destination object's object number, its generation number, and *R* (e.g., *1 0 R*). Use the [AddReference](#addreference-method-pdfexplorer-class) method to add a reference to an existing object:

```csharp
// Creating a reference to the stream at 8 0 obj and adding it to the dictionary at 7 0 obj
string path = pdfexplorer.AddReference("7 0 obj", "Image", "8 0 obj");
```

```text
7 0 obj
<<
/Image 8 0 R
/Type /SampleType
>>
endobj
```

The contents of the destination object can be modified using the path returned by [AddReference](#addreference-method-pdfexplorer-class) in the same way as any other indirect object - the reference remains intact because the object and generation numbers of the destination object are not affected.

### Removing Objects

 The [RemoveObject](#removeobject-method-pdfexplorer-class) method can be used to remove an object from the document. While this method invalidates the former path to the object itself, it does not remove any references to it if it was an indirect object.

```csharp
pdfexplorer.RemoveObject("7 0 obj/Image");
```

```text
7 0 obj
<<
/Type /SampleType
>>
endobj
```

When finished adding, modifying, or removing objects, call [Close](#close-method-pdfexplorer-class) to close the document and save the changes to either [OutputFile](#outputfile-property-pdfexplorer-class), [OutputData](#outputdata-property-pdfexplorer-class), or the stream set in [SetOutputStream](#setoutputstream-method-pdfexplorer-class).

## Property List

*The following is the full list of the properties of the class with short descriptions. Click on the links for further details.*

|  |  |
| --- | --- |
| [InputData](#inputdata-property-pdfexplorer-class) | A byte array containing the PDF document to process. |
| [InputFile](#inputfile-property-pdfexplorer-class) | The PDF file to process. |
| [OutputData](#outputdata-property-pdfexplorer-class) | A byte array containing the PDF document after processing. |
| [OutputFile](#outputfile-property-pdfexplorer-class) | The path to a local file where the output is written. |
| [Overwrite](#overwrite-property-pdfexplorer-class) | Whether the class should overwrite files. |
| [RootObjects](#rootobjects-property-pdfexplorer-class) | A collection of all the root objects contained in the document. |
| [SelectedObjects](#selectedobjects-property-pdfexplorer-class) | A collection of objects that match the current selection. |

## Method List

*The following is the full list of the methods of the class with short descriptions. Click on the links for further details.*

|  |  |
| --- | --- |
| [AddContainer](#addcontainer-method-pdfexplorer-class) | Adds a dictionary or array object to the document. |
| [AddObject](#addobject-method-pdfexplorer-class) | Inserts an object into the document. |
| [AddOpaque](#addopaque-method-pdfexplorer-class) | Adds an opaque piece of PDF to the document. |
| [AddPrimitive](#addprimitive-method-pdfexplorer-class) | Adds a primitive object to the document. |
| [AddReference](#addreference-method-pdfexplorer-class) | Adds an object reference to the document. |
| [AddStream](#addstream-method-pdfexplorer-class) | Adds a stream object to the document. |
| [Close](#close-method-pdfexplorer-class) | Closes the opened document. |
| [Config](#config-method-pdfexplorer-class) | Sets or retrieves a configuration setting. |
| [CreateNew](#createnew-method-pdfexplorer-class) | Creates a new PDF document. |
| [GetObjectData](#getobjectdata-method-pdfexplorer-class) | Returns the content of a stream object. |
| [GetObjectStream](#getobjectstream-method-pdfexplorer-class) | Writes the unparsed and uninterpreted content of a stream object to a stream. |
| [Open](#open-method-pdfexplorer-class) | Opens the document for processing. |
| [RemoveObject](#removeobject-method-pdfexplorer-class) | Removes an object from the document. |
| [Reset](#reset-method-pdfexplorer-class) | Resets the class. |
| [Select](#select-method-pdfexplorer-class) | Selects an object or multiple objects from the document. |
| [SetInputStream](#setinputstream-method-pdfexplorer-class) | Sets the stream containing the PDF document to process. |
| [SetObjectData](#setobjectdata-method-pdfexplorer-class) | Sets the content of a stream object. |
| [SetObjectStream](#setobjectstream-method-pdfexplorer-class) | Sets the content of a stream object from a stream. |
| [SetOutputStream](#setoutputstream-method-pdfexplorer-class) | Sets the stream to write the processed document to. |

## Event List

*The following is the full list of the events fired by the class with short descriptions. Click on the links for further details.*

|  |  |
| --- | --- |
| [Error](#error-event-pdfexplorer-class) | Fired when information is available about errors during data delivery. |
| [Log](#log-event-pdfexplorer-class) | Fired once for each log message. |

## Config Settings

*The following is a list of config settings for the class with short descriptions. Click on the links for further details.*

|  |  |
| --- | --- |
| [CloseInputStreamAfterProcessing](#CloseInputStreamAfterProcessing) | Whether to close the input stream after processing. |
| [CloseOutputStreamAfterProcessing](#CloseOutputStreamAfterProcessing) | Whether to close the output stream after processing. |
| [LogLevel](#LogLevel) | The level of detail that is logged. |
| [SaveChanges](#SaveChanges) | Whether to save changes made to the document. |
| [StringEncoding](#StringEncoding) | The encoding to use for string objects. |
| [TempPath](#TempPath) | The location where temporary files are stored. |
| [BuildInfo](#BuildInfo) | Information about the product's build. |
| [GUIAvailable](#GUIAvailable) | Whether or not a message loop is available for processing events. |
| [LicenseInfo](#LicenseInfo) | Information about the current license. |
| [MaskSensitiveData](#MaskSensitiveData) | Whether sensitive data is masked in log messages. |
| [UseDaemonThreads](#UseDaemonThreads) | Whether threads created by the class are daemon threads. |
| [UseInternalSecurityAPI](#UseInternalSecurityAPI) | Whether or not to use the system security libraries or an internal implementation. |
| [UseVirtualThreads](#UseVirtualThreads) | Whether threads created by the class use virtual threads instead of platform threads. |

# InputData Property ([PDFExplorer](#pdfexplorer-class) Class)

A byte array containing the PDF document to process.

## Syntax

```text
public byte[] getInputData();
public void setInputData(byte[] inputData);
```

## Remarks

This property is used to assign a byte array containing the PDF document to be processed.

This property is not available at design time.

# InputFile Property ([PDFExplorer](#pdfexplorer-class) Class)

The PDF file to process.

## Syntax

```text
public String getInputFile();
public void setInputFile(String inputFile);
```

## Default Value

""

## Remarks

This property is used to provide a path to the PDF document to be processed.

# OutputData Property ([PDFExplorer](#pdfexplorer-class) Class)

A byte array containing the PDF document after processing.

## Syntax

```text
public byte[] getOutputData();
```

## Remarks

This property is used to read the byte array containing the produced output after the operation has completed. It is only set if an output file and output stream have not been assigned via [OutputFile](#outputfile-property-pdfexplorer-class) and [SetOutputStream](#setoutputstream-method-pdfexplorer-class) respectively.

This property is read-only and not available at design time.

# OutputFile Property ([PDFExplorer](#pdfexplorer-class) Class)

The path to a local file where the output is written.

## Syntax

```text
public String getOutputFile();
public void setOutputFile(String outputFile);
```

## Default Value

""

## Remarks

This property is used to provide a path where the resulting PDF document is saved after the operation has completed.

# Overwrite Property ([PDFExplorer](#pdfexplorer-class) Class)

Whether the class should overwrite files.

## Syntax

```text
public boolean isOverwrite();
public void setOverwrite(boolean overwrite);
```

## Default Value

False

## Remarks

This property indicates whether the class overwrites [OutputFile](#outputfile-property-pdfexplorer-class). If set to *false*, an error is thrown whenever [OutputFile](#outputfile-property-pdfexplorer-class) exists before an operation.

# RootObjects Property ([PDFExplorer](#pdfexplorer-class) Class)

A collection of all the root objects contained in the document.

## Syntax

```text
public PDFObjectList getRootObjects();
```

## Remarks

This property is used to access the list of root objects of the document object tree.

The logical structure of the document (the "root") starts at the document trailer. The trailer contains such entries as */Info* and */Root*, which provide a pathway for accessing deeper objects such as pages, forms, and signatures.

This property is read-only and not available at design time.

 Please refer to the [PDFObject](#pdfobject-type) type for a complete list of fields.

# SelectedObjects Property ([PDFExplorer](#pdfexplorer-class) Class)

A collection of objects that match the current selection.

## Syntax

```text
public PDFObjectList getSelectedObjects();
```

## Remarks

This property is used to access the list of objects that match the selection criteria specified in [Select](#select-method-pdfexplorer-class).

This property is read-only and not available at design time.

 Please refer to the [PDFObject](#pdfobject-type) type for a complete list of fields.

# AddContainer Method ([PDFExplorer](#pdfexplorer-class) Class)

Adds a dictionary or array object to the document.

## Syntax

```text
public String addContainer(String basePath, String objectName, boolean dictionary, boolean indirect);
```

## Remarks

This method is used to add a new dictionary or array object to the document at *BasePath*. If adding to an existing dictionary, pass the key that the new object will be added or referenced under to *ObjectName*.

*Dictionary* specifies whether to create a dictionary object.

*Indirect* specifies whether to add the dictionary or array to the indirect (numbered) object list and reference it from *BasePath* instead of creating an in-place object.

This method returns the path to the new object in the document.

Please see [Navigating the Document](#navigating-the-document) for more details about object paths.

# AddObject Method ([PDFExplorer](#pdfexplorer-class) Class)

Inserts an object into the document.

## Syntax

```text
public String addObject(String basePath, int objectType, String objectName, String value, boolean indirect);
```

## Remarks

This method is used to add a new object with value *Value* to the document at *BasePath*. If adding to an existing dictionary, pass the key that the new object will be added or referenced under to *ObjectName*.

*ObjectType* specifies the type of the object. Possible values are:

|  |  |
| --- | --- |
| 0 (potUndefined - default) | Undefined or unknown object type. |
| 1 (potName) | A name. |
| 2 (potString) | A string. |
| 3 (potReal) | A real number. |
| 4 (potInteger) | An integer number. |
| 5 (potBoolean) | A boolean value. |
| 6 (potArray) | An array. This object may have sub-objects. |
| 7 (potDictionary) | A dictionary. This object may have sub-objects. |
| 8 (potStream) | A data stream. |

*Indirect* specifies whether to add the object to the indirect (numbered) object list and reference it from *BasePath* instead of creating an in-place object.

NOTE: This method can be particularly useful to add a primitive object (name, string, real, integer, or boolean) to the list of indirect (numbered) objects.

This method returns the path to the new object in the document.

Please see [Navigating the Document](#navigating-the-document) for more details about object paths.

# AddOpaque Method ([PDFExplorer](#pdfexplorer-class) Class)

Adds an opaque piece of PDF to the document.

## Syntax

```text
public String addOpaque(String basePath, String objectName, String value);
```

## Remarks

This method is used to add an uninterpreted string of PDF objects with value *Value* to the document at *BasePath*. If adding to an existing dictionary, pass the key that the new object will be added under to *ObjectName*.

**Example:**

```csharp
pdfexplorer.InputFile = "input.pdf";
pdfexplorer.OutputFile = "modified.pdf";
pdfexplorer.Open();

string value = "<< /Producer (Secure PDF)\r\n" +
               "/CreationDate (D:20250725102001Z00'00')\r\n" +
               "/ModDate (D:20250725102001Z00'00')\r\n" +
               "/Author (Edvard Grieg)\r\n" +
               "/Title (In the Hall of the Mountain King)\r\n" +
               ">>";
string path = pdfexplorer.AddOpaque("/", "Info", value);

pdfexplorer.Close();
```

 This method returns the path to the new object in the document.

Please see [Navigating the Document](#navigating-the-document) for more details about object paths.

# AddPrimitive Method ([PDFExplorer](#pdfexplorer-class) Class)

Adds a primitive object to the document.

## Syntax

```text
public String addPrimitive(String basePath, String objectName, String value);
```

## Remarks

This method is used to add a new name, string, real (double), integer, or boolean object with value *Value* to the document at *BasePath*. If adding to an existing dictionary, pass the key that the new object will be added under to *ObjectName*.

The class automatically determines the type of the object based on the *Value* parameter.

**Examples:**

```csharp
pdfexplorer.InputFile = "input.pdf";
pdfexplorer.OutputFile = "modified.pdf";
pdfexplorer.Open();

// Adding a name object to the dictionary at 3 0 obj
string namePath = pdfexplorer.AddPrimitive("3 0 obj", "Type", "/Font");

// Adding a string object to the dictionary at 1 0 obj
string stringPath = pdfexplorer.AddPrimitive("1 0 obj", "Name", "John Doe");

// Adding a real object to an array
string realPath = pdfexplorer.AddPrimitive("5 0 obj/Rect", "", "100.5");

// Adding an integer object to an array
string integerPath = pdfexplorer.AddPrimitive("/Root/Pages/Kids[0]/MediaBox", "", "792");

// Adding a boolean object to a dictionary
string booleanPath = pdfexplorer.AddPrimitive("/Root/AcroForm", "NeedAppearances", "true");

pdfexplorer.Close();
```

 This method returns the path to the new object in the document.

Please see [Navigating the Document](#navigating-the-document) for more details about object paths.

# AddReference Method ([PDFExplorer](#pdfexplorer-class) Class)

Adds an object reference to the document.

## Syntax

```text
public String addReference(String basePath, String objectName, String refPath);
```

## Remarks

This method is used to create a new reference to an existing object, such as a page dictionary, at *BasePath*. If adding to an existing dictionary, pass the key that the new reference will be added under to *ObjectName*.

*RefPath* specifies the destination object and must point to one of the indirect (numbered) objects.

This method returns the path to the new object in the document.

Please see [Navigating the Document](#navigating-the-document) for more details about object paths.

# AddStream Method ([PDFExplorer](#pdfexplorer-class) Class)

Adds a stream object to the document.

## Syntax

```text
public String addStream(String basePath, String objectName, byte[] value);
```

## Remarks

This method is used to create a new stream object with value *Value* at *BasePath*. If adding to an existing dictionary, pass the key that the new stream will be referenced under to *ObjectName*.

NOTE: Stream objects are always indirect (i.e., part of the numbered object list).

This method returns the path to the new object in the document.

Please see [Navigating the Document](#navigating-the-document) for more details about object paths.

# Close Method ([PDFExplorer](#pdfexplorer-class) Class)

Closes the opened document.

## Syntax

```text
public void close();
```

## Remarks

This method is used to close the previously opened document. It should always be preceded by a call to [Open](#open-method-pdfexplorer-class).

**Example:**

```csharp
component.InputFile = "input.pdf";
component.Open();
// Some operation
component.Close();
```

 If any changes are made to the document, they are saved automatically to [OutputFile](#outputfile-property-pdfexplorer-class), [OutputData](#outputdata-property-pdfexplorer-class), or the stream set in [SetOutputStream](#setoutputstream-method-pdfexplorer-class) when this method is called. To configure this saving behavior, set [SaveChanges](#SaveChanges).

# Config Method ([PDFExplorer](#pdfexplorer-class) Class)

Sets or retrieves a configuration setting.

## Syntax

```text
public String config(String configurationString);
```

## Remarks

Config is a generic method available in every class. It is used to set and retrieve [configuration settings](#config-settings-pdfexplorer-class) for the class.

These settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the class, access to these *internal properties* is provided through the Config method.

To set a configuration setting named *PROPERTY*, you must call *Config("PROPERTY=VALUE")*, where *VALUE* is the value of the setting expressed as a string. For boolean values, use the strings "True", "False", "0", "1", "Yes", or "No" (case does not matter).

To read (query) the value of a [configuration setting](#config-settings-pdfexplorer-class), you must call *Config("PROPERTY")*. The value will be returned as a string.

# CreateNew Method ([PDFExplorer](#pdfexplorer-class) Class)

Creates a new PDF document.

## Syntax

```text
public void createNew();
```

## Remarks

This method is used to create a blank PDF document with one empty page. Having created the baseline document, use the class's methods (such as [AddStream](#addstream-method-pdfexplorer-class)) to add objects to it.

# GetObjectData Method ([PDFExplorer](#pdfexplorer-class) Class)

Returns the content of a stream object.

## Syntax

```text
public byte[] getObjectData(String path);
```

## Remarks

This method is used to retrieve the content of the PDF stream object at *Path*.

Please see [Navigating the Document](#navigating-the-document) for more details about object paths.

# GetObjectStream Method ([PDFExplorer](#pdfexplorer-class) Class)

Writes the unparsed and uninterpreted content of a stream object to a stream.

## Syntax

```text
public void getObjectStream(String path, java.io.OutputStream outputStream);
```

## Remarks

This method is used to extract the content of the PDF stream object at *Path* to a stream.

Please see [Navigating the Document](#navigating-the-document) for more details about object paths.

# Open Method ([PDFExplorer](#pdfexplorer-class) Class)

Opens the document for processing.

## Syntax

```text
public void open();
```

## Remarks

This method is used to open the document specified in [InputFile](#inputfile-property-pdfexplorer-class), [InputData](#inputdata-property-pdfexplorer-class), or [SetInputStream](#setinputstream-method-pdfexplorer-class) before performing some operation on it, such as accessing or modifying individual PDF objects. When finished, call [Close](#close-method-pdfexplorer-class) to complete or discard the operation.

It is recommended to use this method (alongside [Close](#close-method-pdfexplorer-class)) when performing multiple operations on the document at once.

NOTE: This method populates the [RootObjects](#rootobjects-property-pdfexplorer-class) collection with the keys found in the document trailer dictionary.

# RemoveObject Method ([PDFExplorer](#pdfexplorer-class) Class)

Removes an object from the document.

## Syntax

```text
public void removeObject(String path);
```

## Remarks

This method is used to remove the object at *Path* from the document.

Note the following peculiarities of the PDF format:

- Certain objects ("indirect objects") are global, numbered objects that can be referenced from other objects in the document. To remove an indirect object, all the references to it must be removed first, followed by the object itself.
- Indirect objects may have more than one reference. Removing such an object may inadvertently invalidate other references in the document.

 Please see [Navigating the Document](#navigating-the-document) for more details about object paths.

# Reset Method ([PDFExplorer](#pdfexplorer-class) Class)

Resets the class.

## Syntax

```text
public void reset();
```

## Remarks

This method is used to reset the class's properties and configuration settings to their default values.

# Select Method ([PDFExplorer](#pdfexplorer-class) Class)

Selects an object or multiple objects from the document.

## Syntax

```text
public void select(String filter, boolean clearExistingSelection);
```

## Remarks

This method is used to select objects from the document using an XPath-like language. Upon completion of this method, objects with paths matching *Filter* will be populated in the [SelectedObjects](#selectedobjects-property-pdfexplorer-class) collection.

*ClearExistingSelection* specifies whether [SelectedObjects](#selectedobjects-property-pdfexplorer-class) will be cleared before performing the select operation.

NOTE: Since streams are compound objects consisting of a dictionary and data, when selecting a stream object this method selects its dictionary. Use [GetObjectData](#getobjectdata-method-pdfexplorer-class) or [GetObjectStream](#getobjectstream-method-pdfexplorer-class) to extract the content of stream objects.

Please see [Navigating the Document](#navigating-the-document) for more details about object paths.

# SetInputStream Method ([PDFExplorer](#pdfexplorer-class) Class)

Sets the stream containing the PDF document to process.

## Syntax

```text
public void setInputStream(java.io.InputStream inputStream);
```

## Remarks

This method is used to set the stream from which the class reads the PDF document to be processed. If an input stream is set before the class attempts to perform operations on the document, the class reads the data from the input stream instead of from the [InputFile](#inputfile-property-pdfexplorer-class) or [InputData](#inputdata-property-pdfexplorer-class) properties.

NOTE: It may be useful to additionally set [CloseInputStreamAfterProcessing](#CloseInputStreamAfterProcessing) to *true* when using input streams.

# SetObjectData Method ([PDFExplorer](#pdfexplorer-class) Class)

Sets the content of a stream object.

## Syntax

```text
public void setObjectData(String path, byte[] value);
```

## Remarks

This method is used to set the content of the PDF stream object at *Path*. *Value* specifies the data of the stream.

Please see [Navigating the Document](#navigating-the-document) for more details about object paths.

# SetObjectStream Method ([PDFExplorer](#pdfexplorer-class) Class)

Sets the content of a stream object from a stream.

## Syntax

```text
public void setObjectStream(String path, java.io.InputStream inputStream);
```

## Remarks

This method is used to set the content of the PDF stream object at *Path*, providing the data in a stream.

Please see [Navigating the Document](#navigating-the-document) for more details about object paths.

# SetOutputStream Method ([PDFExplorer](#pdfexplorer-class) Class)

Sets the stream to write the processed document to.

## Syntax

```text
public void setOutputStream(java.io.OutputStream outputStream);
```

## Remarks

This method is used to set the stream to which the class writes the resulting PDF document. If an output stream is set before the class attempts to perform operations on the document, the class writes the data to the output stream instead of writing to [OutputFile](#outputfile-property-pdfexplorer-class) or populating [OutputData](#outputdata-property-pdfexplorer-class).

NOTE: It may be useful to additionally set [CloseOutputStreamAfterProcessing](#CloseOutputStreamAfterProcessing) to *true* when using output streams.

# Error Event ([PDFExplorer](#pdfexplorer-class) Class)

Fired when information is available about errors during data delivery.

## Syntax

```text
public class DefaultPDFExplorerEventListener implements PDFExplorerEventListener {
  ...
  public void error(PDFExplorerErrorEvent e) {}
  ...
}

public class PDFExplorerErrorEvent {
  public int errorCode;
  public String description;
}
```

## Remarks

The Error event is fired in case of exceptional conditions during message processing. Normally the class throws an exception.

The *ErrorCode* parameter contains an error code, and the *Description* parameter contains a textual description of the error. For a list of valid error codes and their descriptions, please refer to the [Error Codes](#trappable-errors-pdfexplorer-class) section.

# Log Event ([PDFExplorer](#pdfexplorer-class) Class)

Fired once for each log message.

## Syntax

```text
public class DefaultPDFExplorerEventListener implements PDFExplorerEventListener {
  ...
  public void log(PDFExplorerLogEvent e) {}
  ...
}

public class PDFExplorerLogEvent {
  public int logLevel;
  public String message;
  public String logType;
}
```

## Remarks

This event is fired once for each log message generated by the class. The verbosity is controlled by the [LogLevel](#LogLevel) configuration setting.

*LogLevel* indicates the detail level of the message. Possible values are:

|  |  |
| --- | --- |
| 0 (None) | No messages are logged. |
| 1 (Info - default) | Informational events such as the basics of the chain validation procedure are logged. |
| 2 (Verbose) | Detailed data such as HTTP requests are logged. |
| 3 (Debug) | Debug data including the full chain validation procedure are logged. |

*Message* is the log message.

*LogType* identifies the type of log entry. Possible values are:

- CertValidator
- Font
- HTTP
- PDFInvalidSignature
- PDFRevocationInfo
- Timestamp
- TSL

# PDFObject Type

A single PDF object.

## Remarks

This type provides access to the properties of an individual document object.

The following fields are available:

- [Container](#PDFObject_f_Container)

- [Disposition](#PDFObject_f_Disposition)

- [ElementCount](#PDFObject_f_ElementCount)

- [GenNumber](#PDFObject_f_GenNumber)

- [Keys](#PDFObject_f_Keys)

- [ObjectNumber](#PDFObject_f_ObjectNumber)

- [ObjectType](#PDFObject_f_ObjectType)

- [Offset](#PDFObject_f_Offset)

- [Path](#PDFObject_f_Path)

- [Size](#PDFObject_f_Size)

- [Value](#PDFObject_f_Value)

## Fields

 **Container** *boolean (read-only)*
*Default Value: False*

Whether the object is a container for other objects (i.e., a dictionary, array, or stream).

 **Disposition** *int (read-only)*
*Default Value: 0*

The method by which the object is addressed in the document.

Possible values are:

|  |  |
| --- | --- |
| 0 (podDirect - default) | The object is recorded in-place. |
| 1 (podReference) | The object is recorded as a reference to an indirect object. |
| 2 (podIndirect) | The object is an indirect object. |

**Example:**

```text
5 0 obj
<<
  /KeyM (Electricity)
>>

...

<<
  /KeyA (Some Value)
  /KeyB << /X /Y >>
  /KeyC 5 0 R
>>
```

- The value of */KeyA* (*Some Value*) is a direct string object.
- The value of */X* (*/Y*) is a direct name object.
- The value of */KeyB* is a direct dictionary object.
- The value of */KeyC* is a reference to the indirect dictionary object *5 0 obj*.
- The value of *5 0 obj* is an indirect dictionary object.

 **ElementCount** *int (read-only)*
*Default Value: 0*

The number of sub-elements in the object, such as keys in the dictionary or elements in the array.

 **GenNumber** *int (read-only)*
*Default Value: 0*

The generation number of the indirect (top-level) object.

 **Keys** *String (read-only)*
*Default Value: ""*

A CRLF-separated list of the keys of the dictionary or indices of the array.

 **ObjectNumber** *int (read-only)*
*Default Value: 0*

The object number of the indirect (top-level) object.

 **ObjectType** *int (read-only)*
*Default Value: 0*

The type of the object.

Possible values are:

|  |  |
| --- | --- |
| 0 (potUndefined - default) | Undefined or unknown object type. |
| 1 (potName) | A name. |
| 2 (potString) | A string. |
| 3 (potReal) | A real number. |
| 4 (potInteger) | An integer number. |
| 5 (potBoolean) | A boolean value. |
| 6 (potArray) | An array. This object may have sub-objects. |
| 7 (potDictionary) | A dictionary. This object may have sub-objects. |
| 8 (potStream) | A data stream. |

 **Offset** *long (read-only)*
*Default Value: 0*

The start offset of the object, in bytes, from the beginning of the PDF document.

 **Path** *String (read-only)*
*Default Value: ""*

The path to the object, for example */Root/Pages*.

 **Size** *long (read-only)*
*Default Value: 0*

The physical length of the object in bytes.

 **Value** *String*
*Default Value: ""*

The value of the object.

NOTE: This field only applies to primitive objects (strings, names, integers, reals, and booleans). To access and modify contents of complex objects such as streams, use [GetObjectData](#getobjectdata-method-pdfexplorer-class) and [SetObjectData](#setobjectdata-method-pdfexplorer-class).

## Constructors

```text
public PDFObject();
```

```text
public PDFObject(int objectType, String path);
```

# Config Settings ([PDFExplorer](#pdfexplorer-class) Class)

 The class accepts one or more of the following *configuration settings*. Configuration settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the class, access to these *internal properties* is provided through the [Config](#config-method-pdfexplorer-class) method.

### PDFExplorer Config Settings

**CloseInputStreamAfterProcessing**: Whether to close the input stream after processing.This setting determines whether the input stream specified in [SetInputStream](#setinputstream-method-pdfexplorer-class) will be closed after processing is complete. The default value is *true*.

**CloseOutputStreamAfterProcessing**: Whether to close the output stream after processing.This setting determines whether the output stream specified in [SetOutputStream](#setoutputstream-method-pdfexplorer-class) will be closed after processing is complete. The default value is *true*.

**LogLevel**: The level of detail that is logged.This setting controls the level of detail that is logged through the [Log](#log-event-pdfexplorer-class) event. Possible values are:

|  |  |
| --- | --- |
| 0 (None) | No messages are logged. |
| 1 (Info - default) | Informational events such as the basics of the chain validation procedure are logged. |
| 2 (Verbose) | Detailed data such as HTTP requests are logged. |
| 3 (Debug) | Debug data including the full chain validation procedure are logged. |

**SaveChanges**: Whether to save changes made to the document.This setting specifies whether and how changes made to the PDF document are saved when [Close](#close-method-pdfexplorer-class) is called. Possible values are:

|  |  |
| --- | --- |
| 0 | Discard all changes. |
| 1 | Save the document to [OutputFile](#outputfile-property-pdfexplorer-class), [OutputData](#outputdata-property-pdfexplorer-class), or the stream set in [SetOutputStream](#setoutputstream-method-pdfexplorer-class), even if it has not been modified. |
| 2 (default) | Save the document to [OutputFile](#outputfile-property-pdfexplorer-class), [OutputData](#outputdata-property-pdfexplorer-class), or the stream set in [SetOutputStream](#setoutputstream-method-pdfexplorer-class), but only if it has been modified. |

**StringEncoding**: The encoding to use for string objects.This setting specifies how the class encodes strings when processing string objects. Possible values are:

|  |  |
| --- | --- |
| Auto (default) | Encode the string as a hex string if no human-readable text is identified; otherwise, encode it as a literal string. |
| Hex | Encode the string as a hex string (e.g., hex:48656C6C6F20776F726C6421). |
| Binary | Encode the string as a literal string, converting to human-readable text when possible (e.g., Hello world!). |

**TempPath**: The location where temporary files are stored.This setting specifies an absolute path to the location on disk where temporary files are stored. It can be useful to reduce memory usage.

### Base Config Settings

**BuildInfo**: Information about the product's build.When queried, this setting will return a string containing information about the product's build.

**GUIAvailable**: Whether or not a message loop is available for processing events.In a GUI-based application, long-running blocking operations may cause the application to stop responding to input until the operation returns. The class will attempt to discover whether or not the application has a message loop and, if one is discovered, it will process events in that message loop during any such blocking operation.

In some non-GUI applications, an invalid message loop may be discovered that will result in errant behavior. In these cases, setting [GUIAvailable](#GUIAvailable) to *false* will ensure that the class does not attempt to process external events.

**LicenseInfo**: Information about the current license.When queried, this setting will return a string containing information about the license this instance of a class is using. It will return the following information:

- Product: The product the license is for.
- Product Key: The key the license was generated from.
- License Source: Where the license was found (e.g., RuntimeLicense, License File).
- License Type: The type of license installed (e.g., Royalty Free, Single Server).
- Last Valid Build: The last valid build number for which the license will work.

**MaskSensitiveData**: Whether sensitive data is masked in log messages.In certain circumstances it may be beneficial to mask sensitive data, like passwords, in log messages. Set this to *true* to mask sensitive data. The default is *true*.

**UseDaemonThreads**: Whether threads created by the class are daemon threads.If set to True (default), when the class creates a thread, the thread's Daemon property will be explicitly set to True. When set to False, the class will not set the Daemon property on the created thread. The default value is True.

**UseInternalSecurityAPI**: Whether or not to use the system security libraries or an internal implementation. When set to *false*, the class will use the system security libraries by default to perform cryptographic functions where applicable.

Setting this configuration setting to *true* tells the class to use the internal implementation instead of using the system security libraries.

 This setting is set to *false* by default on all platforms.

**UseVirtualThreads**: Whether threads created by the class use virtual threads instead of platform threads.If set to *true*, when the class creates a thread, it will be created as a virtual thread instead of a platform thread. Virtual threads are lightweight threads managed by the JVM that are multiplexed onto a small pool of carrier threads, significantly reducing memory usage and platform thread count under high-concurrency workloads. Requires Java 24 or later. The default value is *false*.

# Trappable Errors ([PDFExplorer](#pdfexplorer-class) Class)

### PDFExplorer Errors

|  |  |
| --- | --- |
| 1301 | Invalid path. |
| 1302 | Unsupported object type. |
| 1304 | Object with this name already exists. |
| 1307 | Cannot add direct object to root. |
| 1308 | Cannot add reference to root. |

### PDF Errors

|  |  |
| --- | --- |
| 804 | PDF decompression failed. |
| 805 | Cannot add entry to cross-reference table. |
| 806 | Unsupported field size. |
| 807 | Unsupported Encoding filter. |
| 808 | Unsupported predictor algorithm. |
| 809 | Unsupported document version. |
| 812 | Cannot read PDF file stream. |
| 813 | Cannot write to PDF file stream. |
| 814 | [OutputFile](#outputfile-property-pdfexplorer-class) already exists and [Overwrite](#overwrite-property-pdfexplorer-class) is false. |
| 815 | Invalid parameter. |
| 817 | Bad cross-reference entry. |
| 818 | Invalid object or generation number. |
| 819 | Invalid object stream. |
| 820 | Invalid stream dictionary. |
| 821 | Invalid AcroForm entry. |
| 822 | Invalid Root entry. |
| 823 | Invalid annotation. |
| 824 | The input document is empty. |
| 826 | OpenType font error. The error description contains the detailed message. |
| 828 | Invalid CMS data. The error description contains the detailed message. |
| 835 | Cannot change decryption mode for opened document. |
| 836 | Unsupported Date string. |
| 838 | Cryptographic error. The error description contains the detailed message. |
| 840 | DecryptionCert error. The error description contains the detailed message. |
| 841 | Encryption failed. The error description contains the detailed message. |
| 842 | No proper certificate for encryption found. |
| 846 | Unsupported revision. |
| 847 | Unsupported security handler SubFilter. |
| 848 | Failed to verify permissions. |
| 849 | Invalid password. |
| 850 | Invalid password information. |
| 852 | Unsupported encryption algorithm. |
| 859 | Cannot encrypt encrypted document. |
| 864 | Cannot modify document after signature update. |
| 868 | Cannot encrypt or decrypt object. |
| 869 | Invalid security handler information. |
| 870 | Invalid encrypted data. |
| 871 | Invalid block cipher padding. |
| 872 | Failed to reload signature. |
| 873 | Object is not encrypted. |
| 874 | Unexpected cipher information. |
| 877 | Invalid document. Bad document catalog. |
| 878 | Invalid document Id. |
| 880 | Invalid document. Invalid requirements dictionary. |
| 881 | Invalid linearization dictionary. |
| 882 | Invalid signature information. |
| 883 | Unsupported document format. |
| 890 | Unsupported feature. |
| 891 | Internal error. The error description contains the detailed message. |
| 892 | Unsupported color. |
| 893 | This operation is not supported for this PDF/A level. |
| 894 | Interactive features ([Action](#PDFField_f_Action)) are not supported by PDF/A. Set [EnforcePDFA](#EnforcePDFA) to false or clear the [Action](#PDFField_f_Action) property of the field. |
| 895 | Font file not found. |

### Parsing Errors

|  |  |
| --- | --- |
| 1001 | Bad object. |
| 1002 | Bad document trailer. |
| 1003 | Illegal stream dictionary. |
| 1004 | Illegal string. |
| 1005 | Indirect object expected. |
| 1007 | Invalid reference. |
| 1008 | Invalid reference table. |
| 1009 | Invalid stream data. |
| 1010 | Unexpected character. |
| 1011 | Unexpected EOF. |
| 1012 | Unexpected indirect object in cross-reference table. |
| 1013 | RDF object not found. |
| 1014 | Invalid RDF object. |
| 1015 | Cannot create element with unknown prefix. |
| 1021 | Invalid type in Root object list. |