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Created page with "== Basics == Buffer is an utility object that can be created by using <code>data:createBuffer()</code>. It is used to get more control of what you are writing and reading, by providing bunch of methods for reading and writing bytes for specific primitive data types. ==== Supported primitives ==== {{note|On this page methods, instead of standard type names, will often use primitive names from this table for specifying arguments and return types, keep this in mind while..." |
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Buffer is an utility object that can be created by using <code>data:createBuffer()</code>. It is used to get more control of what you are writing and reading, by providing bunch of methods for reading and writing bytes for specific primitive data types. | |||
== Basics == | == Basics == | ||
==== Supported primitives ==== | ==== Supported primitives ==== | ||
Line 23: | Line 23: | ||
| 4 | | 4 | ||
| A signed 32 bit length integer. Can contain values in range [-2147483648; 2147483647] | | A signed 32 bit length integer. Can contain values in range [-2147483648; 2147483647] | ||
|- | |- | ||
| <code>long</code> | | <code>long</code> | ||
| 8 | | 8 | ||
| A signed 64 bit length integer. Can contain values in range [-9223372036854775808; 9223372036854775807] | | A signed 64 bit length integer. Can contain values in range [-9223372036854775808; 9223372036854775807] | ||
|- | |- | ||
| <code>float</code> | | <code>float</code> | ||
Line 43: | Line 35: | ||
| 8 | | 8 | ||
| A double-precision float-pointing number. | | A double-precision float-pointing number. | ||
|} | |} | ||
Line 59: | Line 47: | ||
| <code>data:createBuffer(capacity {{type|integer}})</code> || {{type|Buffer}} || Creates a buffer with specified initial capacity. | | <code>data:createBuffer(capacity {{type|integer}})</code> || {{type|Buffer}} || Creates a buffer with specified initial capacity. | ||
|} | |} | ||
'''@see''' [[ | '''@see''' [[DataAPI#createBuffer|data:createBuffer]] | ||
Buffer capacity is amount of bytes until buffer will need to reallocate more space. Once it reaches the cap, it reallocates buffer with additional 512 bytes. Buffer can '''not''' exceed the amount of allocated memory specified in permissions settings. | Buffer capacity is amount of bytes until buffer will need to reallocate more space. Once it reaches the cap, it reallocates buffer with additional 512 bytes. Buffer can '''not''' exceed the amount of allocated memory specified in permissions settings. | ||
Line 69: | Line 57: | ||
{| class="wikitable" | {| class="wikitable" | ||
|- | |- | ||
| <code>AA</code> || <code>BB</code> || <code>CC</code> || <code> | | <code>AA</code> || <code>BB</code> || <code>CC</code> || <code>DD</code> | ||
|- | |- | ||
| <code>^^</code> || || || | | <code>^^</code> || || || | ||
Line 85: | Line 73: | ||
{| class="wikitable" | {| class="wikitable" | ||
|- | |- | ||
| <code>AA</code> || <code>BB</code> || <code>CC</code> || <code> | | <code>AA</code> || <code>BB</code> || <code>CC</code> || <code>DD</code> | ||
|- | |- | ||
| || <code>^^</code> || || | | || <code>^^</code> || || | ||
Line 100: | Line 88: | ||
{| class="wikitable" | {| class="wikitable" | ||
|- | |- | ||
| <code>AA</code> || <code>FF</code> || <code>CC</code> || <code> | | <code>AA</code> || <code>FF</code> || <code>CC</code> || <code>DD</code> | ||
|- | |- | ||
| || || <code>^^</code> || | | || || <code>^^</code> || | ||
Line 111: | Line 99: | ||
{| class="wikitable" | {| class="wikitable" | ||
|- | |- | ||
| <code>AA</code> || <code> | | <code>AA</code> || <code>BB</code> || <code>CC</code> || <code>DD</code> | ||
|- | |- | ||
| || || || || <code>^^</code> | | || || || || <code>^^</code> | ||
Line 123: | Line 111: | ||
{| class="wikitable" | {| class="wikitable" | ||
|- | |- | ||
| <code>AA</code> || <code> | | <code>AA</code> || <code>BB</code> || <code>CC</code> || <code>DD</code> | ||
|- | |- | ||
| || || || || <code>^^</code> | | || || || || <code>^^</code> | ||
Line 131: | Line 119: | ||
{| class="wikitable" | {| class="wikitable" | ||
|- | |- | ||
| <code>AA</code> || <code> | | <code>AA</code> || <code>BB</code> || <code>CC</code> || <code>DD</code> | ||
|- | |- | ||
| || || || || <code>^^</code> | | || || || || <code>^^</code> | ||
Line 143: | Line 131: | ||
{| class="wikitable" | {| class="wikitable" | ||
|- | |- | ||
| <code>AA</code> || <code> | | <code>AA</code> || <code>BB</code> || <code>CC</code> || <code>DD</code> || <code>FF</code> || <code>FF</code> | ||
|- | |- | ||
| || || || || || || <code>^^</code> | | || || || || || || <code>^^</code> | ||
Line 149: | Line 137: | ||
== Buffer methods == | == Buffer methods == | ||
This buffer example is going to be used in all code snippets below: | |||
{| class="wikitable" | |||
|- | |||
| <code>AA</code> || <code>BB</code> || <code>CC</code> || <code>DD</code> | |||
|- | |||
| <code>^^</code> || || || | |||
|} | |||
Buffer variable will be named <code>buf</code>. | |||
In case if buffer state changes after method invocation, new state of example buffer will be displayed below the code snippet. | |||
=== General === | |||
General methods of a buffer. | |||
==== getLength ==== | |||
---- | |||
Returns length of this buffer. | |||
{| class="wikitable" | |||
! Arguments !! Return Type | |||
|- | |||
| <code>Buffer:getLength()</code> || {{type|integer}} | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
print(buf:getLength()) --> 4 | |||
</syntaxhighlight> | |||
==== getPosition ==== | |||
---- | |||
Returns current pointer position. | |||
{| class="wikitable" | |||
! Arguments !! Return Type | |||
|- | |||
| <code>getPosition()</code> || {{type|integer}} | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
print(buf:getPosition()) --> 0 | |||
</syntaxhighlight> | |||
==== setPosition ==== | |||
---- | |||
Sets current pointer position. Position will be clamped between <code>0</code> and current buffer length. | |||
'''@see''' [[#getLength|getLength]] | |||
{| class="wikitable" | |||
! Arguments | |||
|- | |||
| <code>setPosition(position {{type|integer}})</code> | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
buf:setPosition(2) | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>AA</code> || <code>BB</code> || <code>CC</code> || <code>DD</code> | |||
|- | |||
| || || <code>^^</code> || | |||
|} | |||
==== clear ==== | |||
---- | |||
Clears this buffer and sets it's pointer position to 0. | |||
{| class="wikitable" | |||
! Arguments | |||
|- | |||
| <code>clear()</code> | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
buf:clear() | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| This buffer is empty, no data to display. | |||
|} | |||
==== available ==== | |||
---- | |||
Returns amount of bytes available to read. | |||
{| class="wikitable" | |||
! Arguments !! Return Type | |||
|- | |||
| <code>available()</code> || {{type|integer}} | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
print(buf:available()) --> 4 | |||
</syntaxhighlight> | |||
==== getMaxCapacity ==== | |||
---- | |||
Returns max buffer capacity. | |||
{| class="wikitable" | |||
! Arguments !! Return Type | |||
|- | |||
| <code>getMaxCapacity()</code> || {{type|integer}} | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
print(buf:getMaxCapacity()) --> 1024000 | |||
</syntaxhighlight> | |||
{{note|This is an output for avatars in unmodified Default permissions group}} | |||
==== close ==== | |||
---- | |||
Closes this buffer, tells garbage collector to free memory used by it. After closing buffer is unable to use, and any usage attempt will cause an error. | |||
{| class="wikitable" | |||
! Arguments | |||
|- | |||
| <code>close()</code> | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
buf:close() | |||
buf:read() --! Throws an error with message "This byte buffer is closed and cant be used anymore" | |||
</syntaxhighlight> | |||
'''@see''' [[#read|read]] | |||
==== isClosed ==== | |||
---- | |||
Checks if this buffer is closed. | |||
{| class="wikitable" | |||
! Arguments !! Return Type | |||
|- | |||
| <code>isClosed()</code> || {{type|boolean}} | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
buf:close() | |||
print(buf:isClosed()) --> true | |||
</syntaxhighlight> | |||
'''@see''' [[#close|close]] | |||
=== Read methods === | |||
Methods of buffer related to reading data. | |||
==== read ==== | |||
---- | |||
Reads a [[#Supported_primitives|<code>byte</code>]] from this buffer and moves pointer by 1. | |||
{| class="wikitable" | |||
! Arguments !! Return Type | |||
|- | |||
| <code>read()</code> || [[#Supported_primitives|<code>byte</code>]] | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
print(buf:read()) --> 170 | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>AA</code> || <code>BB</code> || <code>CC</code> || <code>DD</code> | |||
|- | |||
| || <code>^^</code> || || | |||
|} | |||
==== readShort ==== | |||
---- | |||
Reads a [[#Supported_primitives|<code>short</code>]] from this buffer and moves pointer by 2. | |||
{| class="wikitable" | |||
! Arguments !! Return Type | |||
|- | |||
| <code>readShort()</code> || [[#Supported_primitives|<code>short</code>]] | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
print(buf:readShort()) --> -21829 | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>AA</code> || <code>BB</code> || <code>CC</code> || <code>DD</code> | |||
|- | |||
| || || <code>^^</code> || | |||
|} | |||
==== readUShort ==== | |||
---- | |||
Reads a [[#Supported_primitives|<code>ushort</code>]] from this buffer and moves pointer by 2. | |||
{| class="wikitable" | |||
! Arguments !! Return Type | |||
|- | |||
| <code>readUShort()</code> || [[#Supported_primitives|<code>ushort</code>]] | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
print(buf:readUShort()) --> 43707 | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>AA</code> || <code>BB</code> || <code>CC</code> || <code>DD</code> | |||
|- | |||
| || || <code>^^</code> || | |||
|} | |||
==== readInt ==== | |||
---- | |||
Reads an [[#Supported_primitives|<code>int</code>]] from this buffer and moves pointer by 4. | |||
{| class="wikitable" | |||
! Arguments !! Return Type | |||
|- | |||
| <code>readInt()</code> || [[#Supported_primitives|<code>int</code>]] | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
print(buf:readInt()) --> -1430532899 | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>AA</code> || <code>BB</code> || <code>CC</code> || <code>DD</code> || | |||
|- | |||
| || || || || <code>^^</code> | |||
|} | |||
==== readLong ==== | |||
---- | |||
Reads a [[#Supported_primitives|<code>long</code>]] from this buffer and moves pointer by 8. | |||
{| class="wikitable" | |||
! Arguments !! Return Type | |||
|- | |||
| <code>readLong()</code> || [[#Supported_primitives|<code>long</code>]] | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
print(buf:readLong()) --> -6144092017057071104 | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>AA</code> || <code>BB</code> || <code>CC</code> || <code>DD</code> || | |||
|- | |||
| || || || || <code>^^</code> | |||
|} | |||
==== readFloat ==== | |||
---- | |||
Reads a [[#Supported_primitives|<code>float</code>]] from this buffer and moves pointer by 4. | |||
{| class="wikitable" | |||
! Arguments !! Return Type | |||
|- | |||
| <code>readFloat()</code> || [[#Supported_primitives|<code>float</code>]] | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
print(buf:readFloat()) --> -3.336003e-13 | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>AA</code> || <code>BB</code> || <code>CC</code> || <code>DD</code> || | |||
|- | |||
| || || || || <code>^^</code> | |||
|} | |||
==== readDouble ==== | |||
---- | |||
Reads a [[#Supported_primitives|<code>double</code>]] from this buffer and moves pointer by 8. | |||
{| class="wikitable" | |||
! Arguments !! Return Type | |||
|- | |||
| <code>readDouble()</code> || [[#Supported_primitives|<code>double</code>]] | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
print(buf:readDouble()) --> -7.757649e-103 | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>AA</code> || <code>BB</code> || <code>CC</code> || <code>DD</code> || | |||
|- | |||
| || || || || <code>^^</code> | |||
|} | |||
==== readShortLE ==== | |||
---- | |||
Reads a [[#Supported_primitives|<code>short</code>]] in little-endian format from this buffer and moves pointer by 2. | |||
{| class="wikitable" | |||
! Arguments !! Return Type | |||
|- | |||
| <code>readShortLE()</code> || [[#Supported_primitives|<code>short</code>]] | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
print(buf:readShortLE()) --> -17494 | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>AA</code> || <code>BB</code> || <code>CC</code> || <code>DD</code> | |||
|- | |||
| || || <code>^^</code> || | |||
|} | |||
==== readUShortLE ==== | |||
---- | |||
Reads a [[#Supported_primitives|<code>ushort</code>]] in little-endian format from this buffer and moves pointer by 2. | |||
{| class="wikitable" | |||
! Arguments !! Return Type | |||
|- | |||
| <code>readUShortLE()</code> || [[#Supported_primitives|<code>ushort</code>]] | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
print(buf:readUShortLE()) --> 48042 | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>AA</code> || <code>BB</code> || <code>CC</code> || <code>DD</code> | |||
|- | |||
| || || <code>^^</code> || | |||
|} | |||
==== readIntLE ==== | |||
---- | |||
Reads an [[#Supported_primitives|<code>int</code>]] in little-endian format from this buffer and moves pointer by 4. | |||
{| class="wikitable" | |||
! Arguments !! Return Type | |||
|- | |||
| <code>readIntLE()</code> || [[#Supported_primitives|<code>int</code>]] | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
print(buf:readIntLE()) --> -573785174 | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>AA</code> || <code>BB</code> || <code>CC</code> || <code>DD</code> || | |||
|- | |||
| || || || || <code>^^</code> | |||
|} | |||
==== readLongLE ==== | |||
---- | |||
Reads a [[#Supported_primitives|<code>long</code>]] in little-endian format from this buffer and moves pointer by 8. | |||
{| class="wikitable" | |||
! Arguments !! Return Type | |||
|- | |||
| <code>readLongLE()</code> || [[#Supported_primitives|<code>long</code>]] | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
print(buf:readLongLE()) --> 3721182122 | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>AA</code> || <code>BB</code> || <code>CC</code> || <code>DD</code> || | |||
|- | |||
| || || || || <code>^^</code> | |||
|} | |||
==== readFloatLE ==== | |||
---- | |||
Reads a [[#Supported_primitives|<code>float</code>]] in little-endian format from this buffer and moves pointer by 4. | |||
{| class="wikitable" | |||
! Arguments !! Return Type | |||
|- | |||
| <code>readFloatLE()</code> || [[#Supported_primitives|<code>float</code>]] | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
print(buf:readFloatLE()) --> -1.844071e+18 | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>AA</code> || <code>BB</code> || <code>CC</code> || <code>DD</code> || | |||
|- | |||
| || || || || <code>^^</code> | |||
|} | |||
==== readDoubleLE ==== | |||
---- | |||
Reads a [[#Supported_primitives|<code>double</code>]] in little-endian format from this buffer and moves pointer by 8. | |||
{| class="wikitable" | |||
! Arguments !! Return Type | |||
|- | |||
| <code>readDoubleLE()</code> || [[#Supported_primitives|<code>double</code>]] | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
print(buf:readDoubleLE()) --> 1.838508e-314 | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>AA</code> || <code>BB</code> || <code>CC</code> || <code>DD</code> || | |||
|- | |||
| || || || || <code>^^</code> | |||
|} | |||
==== readString ==== | |||
---- | |||
Reads a string from this buffer. | |||
{| class="wikitable" | |||
! Arguments !! Return Type !! Description | |||
|- | |||
| <code>readString()</code> || {{type|string}} || Reads all bytes from current buffer position to end of the buffer and returns them in form of UTF-8 string. | |||
|- | |||
| <code>readString(length {{type|integer}})</code> || {{type|string}} || Reads specified amount of bytes from current buffer position and returns them in form of UTF-8 string. If <code>length</code> is more than available bytes amount, length will be clamped. | |||
|- | |||
| <code>readString(length {{type|integer}}, encoding {{type|BufferEncoding}})</code> || {{type|string}} || Reads specified amount of bytes from current buffer position and returns them in form of string with specified encoding. If <code>length</code> is more than available bytes amount, length will be clamped. | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
print(buf:readString()) --> "ª»ÌÝ" | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>AA</code> || <code>BB</code> || <code>CC</code> || <code>DD</code> || | |||
|- | |||
| || || || || <code>^^</code> | |||
|} | |||
==== readBase64 ==== | |||
---- | |||
Reads a Base64 string from this buffer. | |||
{| class="wikitable" | |||
! Arguments !! Return Type !! Description | |||
|- | |||
| <code>readBase64()</code> || {{type|string}} || Reads all bytes from current buffer position to end of the buffer and returns them in form of Base64 encoded byte array. | |||
|- | |||
| <code>readBase64(length {{type|integer}})</code> || {{type|string}} || Reads specified amount of bytes from current buffer position and returns them in form of Base64 encoded byte array. If <code>length</code> is more than available bytes amount, length will be clamped. | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
print(buf:readBase64()) --> "qrvM7g==" | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>AA</code> || <code>BB</code> || <code>CC</code> || <code>DD</code> || | |||
|- | |||
| || || || || <code>^^</code> | |||
|} | |||
==== readByteArray ==== | |||
---- | |||
Reads a byte array from this buffer. | |||
{| class="wikitable" | |||
! Arguments !! Return Type !! Description | |||
|- | |||
| <code>readByteArray()</code> || {{type|string}} || Reads all bytes from current buffer position to end of the buffer and returns them in form of Lua string byte array. | |||
|- | |||
| <code>readByteArray(length {{type|integer}})</code> || {{type|string}} || Reads specified amount of bytes from current buffer position and returns them in form of Lua string byte array. If <code>length</code> is more than available bytes amount, length will be clamped. | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
print(buf:readByteArray()) --> [raw data] | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>AA</code> || <code>BB</code> || <code>CC</code> || <code>DD</code> || | |||
|- | |||
| || || || || <code>^^</code> | |||
|} | |||
=== Write methods === | |||
==== write ==== | |||
---- | |||
Writes a [[#Supported_primitives|<code>byte</code>]] to this buffer and moves pointer by 1. | |||
{| class="wikitable" | |||
! Arguments | |||
|- | |||
| <code>write(value [[#Supported_primitives|<code>byte</code>]])</code> | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
buf:write(255) | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>FF</code> || <code>BB</code> || <code>CC</code> || <code>DD</code> | |||
|- | |||
| || <code>^^</code> || || | |||
|} | |||
==== writeShort ==== | |||
---- | |||
Writes a [[#Supported_primitives|<code>short</code>]] to this buffer and moves pointer by 2. | |||
{| class="wikitable" | |||
! Arguments | |||
|- | |||
| <code>writeShort(value [[#Supported_primitives|<code>short</code>]])</code> | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
buf:writeShort(32767) | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>7F</code> || <code>FF</code> || <code>CC</code> || <code>DD</code> | |||
|- | |||
| || || <code>^^</code> || | |||
|} | |||
==== writeUShort ==== | |||
---- | |||
Writes a [[#Supported_primitives|<code>ushort</code>]] to this buffer and moves pointer by 2. | |||
{| class="wikitable" | |||
! Arguments | |||
|- | |||
| <code>writeUShort(value [[#Supported_primitives|<code>ushort</code>]])</code> | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
buf:writeUShort(32767) | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>7F</code> || <code>FF</code> || <code>CC</code> || <code>DD</code> | |||
|- | |||
| || || <code>^^</code> || | |||
|} | |||
==== writeInt ==== | |||
---- | |||
Writes an [[#Supported_primitives|<code>int</code>]] to this buffer and moves pointer by 4. | |||
{| class="wikitable" | |||
! Arguments | |||
|- | |||
| <code>writeInt(value [[#Supported_primitives|<code>int</code>]])</code> | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
buf:writeInt(2147483647) | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>7F</code> || <code>FF</code> || <code>FF</code> || <code>FF</code> | |||
|- | |||
| || || || || <code>^^</code> | |||
|} | |||
==== writeLong ==== | |||
---- | |||
Writes a [[#Supported_primitives|<code>long</code>]] to this buffer and moves pointer by 8. | |||
{| class="wikitable" | |||
! Arguments | |||
|- | |||
| <code>writeLong(value [[#Supported_primitives|<code>long</code>]])</code> | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
buf:writeLong(9223372036854775807) | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>7F</code> || <code>FF</code> || <code>FF</code> || <code>FF</code> || <code>FF</code> || <code>FF</code> || <code>FF</code> || <code>FF</code> | |||
|- | |||
| || || || || || || || || <code>^^</code> | |||
|} | |||
==== writeFloat ==== | |||
---- | |||
Writes a [[#Supported_primitives|<code>float</code>]] to this buffer and moves pointer by 4. | |||
{| class="wikitable" | |||
! Arguments | |||
|- | |||
| <code>writeFloat(value [[#Supported_primitives|<code>float</code>]])</code> | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
buf:writeFloat(50.0) | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>42</code> || <code>48</code> || <code>00</code> || <code>00</code> | |||
|- | |||
| || || || || <code>^^</code> | |||
|} | |||
==== writeDouble ==== | |||
---- | |||
Writes a [[#Supported_primitives|<code>double</code>]] to this buffer and moves pointer by 8. | |||
{| class="wikitable" | |||
! Arguments | |||
|- | |||
| <code>writeDouble(value [[#Supported_primitives|<code>double</code>]])</code> | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
buf:writeDouble(50.0) | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>40</code> || <code>49</code> || <code>00</code> || <code>00</code> || <code>00</code> || <code>00</code> || <code>00</code> || <code>00</code> | |||
|- | |||
| || || || || || || || || <code>^^</code> | |||
|} | |||
==== writeShortLE ==== | |||
---- | |||
Writes a [[#Supported_primitives|<code>short</code>]] in little-endian format to this buffer and moves pointer by 2. | |||
{| class="wikitable" | |||
! Arguments | |||
|- | |||
| <code>writeShortLE(value [[#Supported_primitives|<code>short</code>]])</code> | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
buf:writeShortLE(32767) | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>FF</code> || <code>7F</code> || <code>CC</code> || <code>DD</code> | |||
|- | |||
| || || <code>^^</code> || | |||
|} | |||
==== writeUShortLE ==== | |||
---- | |||
Writes a [[#Supported_primitives|<code>ushort</code>]] in little-endian format to this buffer and moves pointer by 2. | |||
{| class="wikitable" | |||
! Arguments | |||
|- | |||
| <code>writeUShortLE(value [[#Supported_primitives|<code>ushort</code>]])</code> | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
buf:writeUShortLE(32767) | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>FF</code> || <code>7F</code> || <code>CC</code> || <code>DD</code> | |||
|- | |||
| || || <code>^^</code> || | |||
|} | |||
==== writeIntLE ==== | |||
---- | |||
Writes an [[#Supported_primitives|<code>int</code>]] in little-endian format to this buffer and moves pointer by 4. | |||
{| class="wikitable" | |||
! Arguments | |||
|- | |||
| <code>writeIntLE(value [[#Supported_primitives|<code>int</code>]])</code> | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
buf:writeIntLE(2147483647) | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>FF</code> || <code>FF</code> || <code>FF</code> || <code>7F</code> | |||
|- | |||
| || || || || <code>^^</code> | |||
|} | |||
==== writeLongLE ==== | |||
---- | |||
Writes a [[#Supported_primitives|<code>long</code>]] in little-endian format to this buffer and moves pointer by 8. | |||
{| class="wikitable" | |||
! Arguments | |||
|- | |||
| <code>writeLongLE(value [[#Supported_primitives|<code>long</code>]])</code> | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
buf:writeLongLE(9223372036854775807) | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>FF</code> || <code>FF</code> || <code>FF</code> || <code>FF</code> || <code>FF</code> || <code>FF</code> || <code>FF</code> || <code>7F</code> | |||
|- | |||
| || || || || || || || || <code>^^</code> | |||
|} | |||
==== writeFloatLE ==== | |||
---- | |||
Writes a [[#Supported_primitives|<code>float</code>]] in little-endian format to this buffer and moves pointer by 4. | |||
{| class="wikitable" | |||
! Arguments | |||
|- | |||
| <code>writeFloatLE(value [[#Supported_primitives|<code>float</code>]])</code> | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
buf:writeFloatLE(50.0) | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>00</code> || <code>00</code> || <code>48</code> || <code>42</code> | |||
|- | |||
| || || || || <code>^^</code> | |||
|} | |||
==== writeDoubleLE ==== | |||
---- | |||
Writes a [[#Supported_primitives|<code>double</code>]] in little-endian format to this buffer and moves pointer by 8. | |||
{| class="wikitable" | |||
! Arguments | |||
|- | |||
| <code>writeDoubleLE(value [[#Supported_primitives|<code>double</code>]])</code> | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
buf:writeDoubleLE(50.0) | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>00</code> || <code>00</code> || <code>00</code> || <code>00</code> || <code>00</code> || <code>00</code> || <code>49</code> || <code>40</code> | |||
|- | |||
| || || || || || || || || <code>^^</code> | |||
|} | |||
==== writeString ==== | |||
---- | |||
Writes a string in buffer, and returns it's length in bytes. | |||
{| class="wikitable" | |||
! Arguments !! Return type !! Description | |||
|- | |||
| <code>writeString(value {{type|string}})</code> || {{type|integer}} || Writes a string in UTF-8 encoding. | |||
|- | |||
| <code>writeString(value {{type|string}}, encoding {{type|BufferEncoding}})</code> || {{type|integer}} || Writes a string in specified encoding. | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
print(buf:writeString("Hello, world!")) --> 13 | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>48</code> || <code>65</code> || <code>6C</code> || <code>6C</code> || <code>6F</code> || <code>2C</code> || <code>20</code> || <code>77</code> || <code>6F</code> || <code>72</code> || <code>6C</code> || <code>64</code> || <code>21</code> || | |||
|- | |||
| || || || || || || || || || || || || || <code>^^</code> | |||
|} | |||
==== writeBase64 ==== | |||
---- | |||
Decodes Base64 byte array and writes in to buffer. Returns amount of written bytes. | |||
{| class="wikitable" | |||
! Arguments !! Return type | |||
|- | |||
| <code>writeBase64(value {{type|string}})</code> || {{type|integer}} | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
print(buf:writeBase64("TWVvdw==")) --> 4 | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>4D</code> || <code>65</code> || <code>6F</code> || <code>77</code> || | |||
|- | |||
| || || || || <code>^^</code> | |||
|} | |||
==== writeByteArray ==== | |||
---- | |||
Write a lua string byte array to buffer. Returns amount of written bytes. | |||
{| class="wikitable" | |||
! Arguments !! Return type | |||
|- | |||
| <code>writeByteArray(value {{type|string}})</code> || {{type|integer}} | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
print(buf:writeByteArray("\xAA\xBB\xCC\xDD")) --> 4 | |||
</syntaxhighlight> | |||
{| class="wikitable" | |||
|- | |||
| <code>AA</code> || <code>BB</code> || <code>CC</code> || <code>DD</code> || | |||
|- | |||
| || || || || <code>^^</code> | |||
|} | |||
=== Streams === | |||
Methods for working with Input and Output streams | |||
==== readFromStream ==== | |||
---- | |||
Reads provided stream, and writes it's data to this buffer. Returns amount of bytes written to buffer. | |||
{| class="wikitable" | |||
! Arguments !! Return type !! Description | |||
|- | |||
| <code>readFromStream(stream {{type|InputStream}})</code> || {{type|integer}} || Reads provided stream to either max capacity of buffer, or end of stream. | |||
|- | |||
| <code>readFromStream(stream {{type|InputStream}}, amount {{type|integer}})</code> || {{type|integer}} || Trying to read specified amount of bytes from provided stream. Resulting amount of read bytes might be less than specified. | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
-- Opening resource from avatar resources | |||
local is = resources:get("buf_read_test.txt") | |||
-- Reading content of resource, printing it's length | |||
print(buf:readFromStream(is)) --> 13 | |||
-- Resetting buffer position so it can read string from start | |||
buf:setPosition(0) | |||
-- Reading string | |||
print(buf:readString()) --> "Hello, world!" | |||
-- Closing input stream | |||
is:close() | |||
</syntaxhighlight> | |||
'''@see''' [[ResourcesAPI#get|resources:get]], [[#setPosition|setPosition]], [[#readString|readString]] | |||
{| class="wikitable" | |||
|- | |||
| <code>48</code> || <code>65</code> || <code>6C</code> || <code>6C</code> || <code>6F</code> || <code>2C</code> || <code>20</code> || <code>77</code> || <code>6F</code> || <code>72</code> || <code>6C</code> || <code>64</code> || <code>21</code> || | |||
|- | |||
| || || || || || || || || || || || || || <code>^^</code> | |||
|} | |||
==== writeToStream ==== | |||
---- | |||
Writes bytes from this buffer to provided output stream. Returns amount of bytes written to stream. | |||
{| class="wikitable" | |||
! Arguments !! Return type !! Description | |||
|- | |||
| <code>writeToStream(stream {{type|OutputStream}})</code> || {{type|integer}} || Writes all available bytes to provided stream. | |||
|- | |||
| <code>writeToStream(stream {{type|OutputStream}}, amount {{type|integer}})</code> || {{type|integer}} || Writes specified amount of bytes from current position to provided stream. | |||
|} | |||
<syntaxhighlight lang="lua"> | |||
-- Opening output stream with FileAPI | |||
local os = file:openWriteStream("buf_write_test.txt") | |||
-- Preparing future file content | |||
buf:writeString("Hello, world!") | |||
-- Resetting buffer position, so buffer can write data to stream from start | |||
buf:setPosition(0) | |||
-- Writing file data | |||
buf:writeToStream(os) | |||
-- Closing output stream | |||
os:close() | |||
</syntaxhighlight> | |||
'''@see''' [[FileAPI#openWriteStream|file:openWriteStream]], [[#writeString|writeString]], [[#writeString|setPosition]], [[OutputStream#close|OutputStream:close]] | |||
{| class="wikitable" | |||
|- | |||
| <code>48</code> || <code>65</code> || <code>6C</code> || <code>6C</code> || <code>6F</code> || <code>2C</code> || <code>20</code> || <code>77</code> || <code>6F</code> || <code>72</code> || <code>6C</code> || <code>64</code> || <code>21</code> || | |||
|- | |||
| || || || || || || || || || || || || || <code>^^</code> | |||
|} |
Latest revision as of 10:57, 29 September 2024
Buffer is an utility object that can be created by using data:createBuffer()
. It is used to get more control of what you are writing and reading, by providing bunch of methods for reading and writing bytes for specific primitive data types.
Basics
Supported primitives
On this page methods, instead of standard type names, will often use primitive names from this table for specifying arguments and return types, keep this in mind while reading this page.
Type name | Size in bytes | Description |
---|---|---|
byte
|
1 | An unsigned 8 bit length integer. Can contain values in range [0; 255] |
short
|
2 | A signed 16 bit length integer. Can contain values in range [-32768; 32767] |
ushort
|
2 | An unsigned 16 bit length integer. Can contain values in range [0; 65535] |
int
|
4 | A signed 32 bit length integer. Can contain values in range [-2147483648; 2147483647] |
long
|
8 | A signed 64 bit length integer. Can contain values in range [-9223372036854775808; 9223372036854775807] |
float
|
4 | A single-precision float-pointing number. |
double
|
8 | A double-precision float-pointing number. |
Buffer instantiation and capacity
There are two possible ways to instantiate a buffer:
Arguments | Returns | Description |
---|---|---|
data:createBuffer() |
Buffer | Creates a buffer with initial capacity of 512 bytes. |
data:createBuffer(capacity integer) |
Buffer | Creates a buffer with specified initial capacity. |
@see data:createBuffer
Buffer capacity is amount of bytes until buffer will need to reallocate more space. Once it reaches the cap, it reallocates buffer with additional 512 bytes. Buffer can not exceed the amount of allocated memory specified in permissions settings.
How buffer works
Buffers have a pointer to current byte in a buffer, and it is moved by read and write methods. Buffers has same pointer both for write and read operations.
For example:
AA |
BB |
CC |
DD
|
^^ |
Right now buffer is pointing to first byte (index 0), so when we do the following:
print(buf:read()) --> 170
@see read
Buffer will be pointing to the next byte:
AA |
BB |
CC |
DD
|
^^ |
Now when we will write a byte in a buffer:
buf:write(255)
@see write
It will rewrite the pointed byte, and buffer will be pointing to the next byte.
AA |
FF |
CC |
DD
|
^^ |
Once buffer reaches it's current end, read methods will act different
- read will return -1.
- Integer and float pointing read methods will read until end, and will fill remaining bytes with nulls.
- readString, readByteArray, and readBase64 will read until end and stop. If pointer is already at end, it will return empty result.
AA |
BB |
CC |
DD
| |
^^
|
print(buf:read()) --> -1
print(buf:readString()) --> ""
@see read, readString
AA |
BB |
CC |
DD
| |
^^
|
Write methods will add new bytes if buffer is pointing it's current end, and will move the pointer further:
AA |
BB |
CC |
DD
| |
^^
|
buf:writeUShort(65535)
@see writeUShort
This is how our buffer will look like now:
AA |
BB |
CC |
DD |
FF |
FF
| |
^^
|
Buffer methods
This buffer example is going to be used in all code snippets below:
AA |
BB |
CC |
DD
|
^^ |
Buffer variable will be named buf
.
In case if buffer state changes after method invocation, new state of example buffer will be displayed below the code snippet.
General
General methods of a buffer.
getLength
Returns length of this buffer.
Arguments | Return Type |
---|---|
Buffer:getLength() |
integer |
print(buf:getLength()) --> 4
getPosition
Returns current pointer position.
Arguments | Return Type |
---|---|
getPosition() |
integer |
print(buf:getPosition()) --> 0
setPosition
Sets current pointer position. Position will be clamped between 0
and current buffer length.
@see getLength
Arguments |
---|
setPosition(position integer)
|
buf:setPosition(2)
AA |
BB |
CC |
DD
|
^^ |
clear
Clears this buffer and sets it's pointer position to 0.
Arguments |
---|
clear()
|
buf:clear()
This buffer is empty, no data to display. |
available
Returns amount of bytes available to read.
Arguments | Return Type |
---|---|
available() |
integer |
print(buf:available()) --> 4
getMaxCapacity
Returns max buffer capacity.
Arguments | Return Type |
---|---|
getMaxCapacity() |
integer |
print(buf:getMaxCapacity()) --> 1024000
This is an output for avatars in unmodified Default permissions group
close
Closes this buffer, tells garbage collector to free memory used by it. After closing buffer is unable to use, and any usage attempt will cause an error.
Arguments |
---|
close()
|
buf:close()
buf:read() --! Throws an error with message "This byte buffer is closed and cant be used anymore"
@see read
isClosed
Checks if this buffer is closed.
Arguments | Return Type |
---|---|
isClosed() |
boolean |
buf:close()
print(buf:isClosed()) --> true
@see close
Read methods
Methods of buffer related to reading data.
read
Reads a byte
from this buffer and moves pointer by 1.
Arguments | Return Type |
---|---|
read() |
byte
|
print(buf:read()) --> 170
AA |
BB |
CC |
DD
|
^^ |
readShort
Reads a short
from this buffer and moves pointer by 2.
Arguments | Return Type |
---|---|
readShort() |
short
|
print(buf:readShort()) --> -21829
AA |
BB |
CC |
DD
|
^^ |
readUShort
Reads a ushort
from this buffer and moves pointer by 2.
Arguments | Return Type |
---|---|
readUShort() |
ushort
|
print(buf:readUShort()) --> 43707
AA |
BB |
CC |
DD
|
^^ |
readInt
Reads an int
from this buffer and moves pointer by 4.
Arguments | Return Type |
---|---|
readInt() |
int
|
print(buf:readInt()) --> -1430532899
AA |
BB |
CC |
DD |
|
^^
|
readLong
Reads a long
from this buffer and moves pointer by 8.
Arguments | Return Type |
---|---|
readLong() |
long
|
print(buf:readLong()) --> -6144092017057071104
AA |
BB |
CC |
DD |
|
^^
|
readFloat
Reads a float
from this buffer and moves pointer by 4.
Arguments | Return Type |
---|---|
readFloat() |
float
|
print(buf:readFloat()) --> -3.336003e-13
AA |
BB |
CC |
DD |
|
^^
|
readDouble
Reads a double
from this buffer and moves pointer by 8.
Arguments | Return Type |
---|---|
readDouble() |
double
|
print(buf:readDouble()) --> -7.757649e-103
AA |
BB |
CC |
DD |
|
^^
|
readShortLE
Reads a short
in little-endian format from this buffer and moves pointer by 2.
Arguments | Return Type |
---|---|
readShortLE() |
short
|
print(buf:readShortLE()) --> -17494
AA |
BB |
CC |
DD
|
^^ |
readUShortLE
Reads a ushort
in little-endian format from this buffer and moves pointer by 2.
Arguments | Return Type |
---|---|
readUShortLE() |
ushort
|
print(buf:readUShortLE()) --> 48042
AA |
BB |
CC |
DD
|
^^ |
readIntLE
Reads an int
in little-endian format from this buffer and moves pointer by 4.
Arguments | Return Type |
---|---|
readIntLE() |
int
|
print(buf:readIntLE()) --> -573785174
AA |
BB |
CC |
DD |
|
^^
|
readLongLE
Reads a long
in little-endian format from this buffer and moves pointer by 8.
Arguments | Return Type |
---|---|
readLongLE() |
long
|
print(buf:readLongLE()) --> 3721182122
AA |
BB |
CC |
DD |
|
^^
|
readFloatLE
Reads a float
in little-endian format from this buffer and moves pointer by 4.
Arguments | Return Type |
---|---|
readFloatLE() |
float
|
print(buf:readFloatLE()) --> -1.844071e+18
AA |
BB |
CC |
DD |
|
^^
|
readDoubleLE
Reads a double
in little-endian format from this buffer and moves pointer by 8.
Arguments | Return Type |
---|---|
readDoubleLE() |
double
|
print(buf:readDoubleLE()) --> 1.838508e-314
AA |
BB |
CC |
DD |
|
^^
|
readString
Reads a string from this buffer.
Arguments | Return Type | Description |
---|---|---|
readString() |
string | Reads all bytes from current buffer position to end of the buffer and returns them in form of UTF-8 string. |
readString(length integer) |
string | Reads specified amount of bytes from current buffer position and returns them in form of UTF-8 string. If length is more than available bytes amount, length will be clamped.
|
readString(length integer, encoding BufferEncoding) |
string | Reads specified amount of bytes from current buffer position and returns them in form of string with specified encoding. If length is more than available bytes amount, length will be clamped.
|
print(buf:readString()) --> "ª»ÌÝ"
AA |
BB |
CC |
DD |
|
^^
|
readBase64
Reads a Base64 string from this buffer.
Arguments | Return Type | Description |
---|---|---|
readBase64() |
string | Reads all bytes from current buffer position to end of the buffer and returns them in form of Base64 encoded byte array. |
readBase64(length integer) |
string | Reads specified amount of bytes from current buffer position and returns them in form of Base64 encoded byte array. If length is more than available bytes amount, length will be clamped.
|
print(buf:readBase64()) --> "qrvM7g=="
AA |
BB |
CC |
DD |
|
^^
|
readByteArray
Reads a byte array from this buffer.
Arguments | Return Type | Description |
---|---|---|
readByteArray() |
string | Reads all bytes from current buffer position to end of the buffer and returns them in form of Lua string byte array. |
readByteArray(length integer) |
string | Reads specified amount of bytes from current buffer position and returns them in form of Lua string byte array. If length is more than available bytes amount, length will be clamped.
|
print(buf:readByteArray()) --> [raw data]
AA |
BB |
CC |
DD |
|
^^
|
Write methods
write
Writes a byte
to this buffer and moves pointer by 1.
Arguments |
---|
write(value
|
buf:write(255)
FF |
BB |
CC |
DD
|
^^ |
writeShort
Writes a short
to this buffer and moves pointer by 2.
Arguments |
---|
writeShort(value
|
buf:writeShort(32767)
7F |
FF |
CC |
DD
|
^^ |
writeUShort
Writes a ushort
to this buffer and moves pointer by 2.
Arguments |
---|
writeUShort(value
|
buf:writeUShort(32767)
7F |
FF |
CC |
DD
|
^^ |
writeInt
Writes an int
to this buffer and moves pointer by 4.
Arguments |
---|
writeInt(value
|
buf:writeInt(2147483647)
7F |
FF |
FF |
FF
| |
^^
|
writeLong
Writes a long
to this buffer and moves pointer by 8.
Arguments |
---|
writeLong(value
|
buf:writeLong(9223372036854775807)
7F |
FF |
FF |
FF |
FF |
FF |
FF |
FF
| |
^^
|
writeFloat
Writes a float
to this buffer and moves pointer by 4.
Arguments |
---|
writeFloat(value
|
buf:writeFloat(50.0)
42 |
48 |
00 |
00
| |
^^
|
writeDouble
Writes a double
to this buffer and moves pointer by 8.
Arguments |
---|
writeDouble(value
|
buf:writeDouble(50.0)
40 |
49 |
00 |
00 |
00 |
00 |
00 |
00
| |
^^
|
writeShortLE
Writes a short
in little-endian format to this buffer and moves pointer by 2.
Arguments |
---|
writeShortLE(value
|
buf:writeShortLE(32767)
FF |
7F |
CC |
DD
|
^^ |
writeUShortLE
Writes a ushort
in little-endian format to this buffer and moves pointer by 2.
Arguments |
---|
writeUShortLE(value
|
buf:writeUShortLE(32767)
FF |
7F |
CC |
DD
|
^^ |
writeIntLE
Writes an int
in little-endian format to this buffer and moves pointer by 4.
Arguments |
---|
writeIntLE(value
|
buf:writeIntLE(2147483647)
FF |
FF |
FF |
7F
| |
^^
|
writeLongLE
Writes a long
in little-endian format to this buffer and moves pointer by 8.
Arguments |
---|
writeLongLE(value
|
buf:writeLongLE(9223372036854775807)
FF |
FF |
FF |
FF |
FF |
FF |
FF |
7F
| |
^^
|
writeFloatLE
Writes a float
in little-endian format to this buffer and moves pointer by 4.
Arguments |
---|
writeFloatLE(value
|
buf:writeFloatLE(50.0)
00 |
00 |
48 |
42
| |
^^
|
writeDoubleLE
Writes a double
in little-endian format to this buffer and moves pointer by 8.
Arguments |
---|
writeDoubleLE(value
|
buf:writeDoubleLE(50.0)
00 |
00 |
00 |
00 |
00 |
00 |
49 |
40
| |
^^
|
writeString
Writes a string in buffer, and returns it's length in bytes.
Arguments | Return type | Description |
---|---|---|
writeString(value string) |
integer | Writes a string in UTF-8 encoding. |
writeString(value string, encoding BufferEncoding) |
integer | Writes a string in specified encoding. |
print(buf:writeString("Hello, world!")) --> 13
48 |
65 |
6C |
6C |
6F |
2C |
20 |
77 |
6F |
72 |
6C |
64 |
21 |
|
^^
|
writeBase64
Decodes Base64 byte array and writes in to buffer. Returns amount of written bytes.
Arguments | Return type |
---|---|
writeBase64(value string) |
integer |
print(buf:writeBase64("TWVvdw==")) --> 4
4D |
65 |
6F |
77 |
|
^^
|
writeByteArray
Write a lua string byte array to buffer. Returns amount of written bytes.
Arguments | Return type |
---|---|
writeByteArray(value string) |
integer |
print(buf:writeByteArray("\xAA\xBB\xCC\xDD")) --> 4
AA |
BB |
CC |
DD |
|
^^
|
Streams
Methods for working with Input and Output streams
readFromStream
Reads provided stream, and writes it's data to this buffer. Returns amount of bytes written to buffer.
Arguments | Return type | Description |
---|---|---|
readFromStream(stream InputStream) |
integer | Reads provided stream to either max capacity of buffer, or end of stream. |
readFromStream(stream InputStream, amount integer) |
integer | Trying to read specified amount of bytes from provided stream. Resulting amount of read bytes might be less than specified. |
-- Opening resource from avatar resources
local is = resources:get("buf_read_test.txt")
-- Reading content of resource, printing it's length
print(buf:readFromStream(is)) --> 13
-- Resetting buffer position so it can read string from start
buf:setPosition(0)
-- Reading string
print(buf:readString()) --> "Hello, world!"
-- Closing input stream
is:close()
@see resources:get, setPosition, readString
48 |
65 |
6C |
6C |
6F |
2C |
20 |
77 |
6F |
72 |
6C |
64 |
21 |
|
^^
|
writeToStream
Writes bytes from this buffer to provided output stream. Returns amount of bytes written to stream.
Arguments | Return type | Description |
---|---|---|
writeToStream(stream OutputStream) |
integer | Writes all available bytes to provided stream. |
writeToStream(stream OutputStream, amount integer) |
integer | Writes specified amount of bytes from current position to provided stream. |
-- Opening output stream with FileAPI
local os = file:openWriteStream("buf_write_test.txt")
-- Preparing future file content
buf:writeString("Hello, world!")
-- Resetting buffer position, so buffer can write data to stream from start
buf:setPosition(0)
-- Writing file data
buf:writeToStream(os)
-- Closing output stream
os:close()
@see file:openWriteStream, writeString, setPosition, OutputStream:close
48 |
65 |
6C |
6C |
6F |
2C |
20 |
77 |
6F |
72 |
6C |
64 |
21 |
|
^^
|