B4J Question [Solved] Reading version number in manifest.txt from a b4xlib

[aeric]

The only way I know is to unzip the library to a temp folder (using a library such as Archiver), read the txt file into a Map and delete the folder recursively.
Any other suggestion?

 

[Erel]

[B4X] Unzip single entry from a zip file / ZipToMap / MapToZip

B4A + B4J code. Reads the data of a single entry. 'Depends on JavaObject. Returns 0 bytes array if entry not found. Private Sub UnzipEntry(ZipPath As String, Entry As String) As Byte() Dim result() As Byte Dim ZipFile As JavaObject...

www.b4x.com

 

[aeric]

I get this code from DeepSeek.

' Reads the version from a .b4xlib file (B4A / B4J)
Sub GetB4XLibVersion (LibPath As String) As String
    Dim jZip As JavaObject
    jZip.InitializeNewInstance("java.util.zip.ZipFile", Array(LibPath))
    
    Dim jManifestEntry As JavaObject = jZip.RunMethod("getEntry", Array("manifest.txt"))
    If jManifestEntry.IsInitialized Then
        Dim jInputStream As JavaObject = jZip.RunMethod("getInputStream", Array(jManifestEntry))
        Dim jScanner As JavaObject
        jScanner.InitializeNewInstance("java.util.Scanner", Array(jInputStream, "UTF-8"))
        jScanner.RunMethod("useDelimiter", Array("\\A")) ' Read entire stream
        Dim manifestText As String = jScanner.RunMethod("next", Null)
        jScanner.RunMethod("close", Null)
        
        ' Parse version (e.g., "Version=1.00")
        Dim lines() As String = Regex.Split(CRLF, manifestText)
        For Each line As String In lines
            If line.StartsWith("Version=") Then
                Return line.SubString(8) ' Extract version number
            End If
        Next
    End If
    
    Return "Unknown"
End Sub

 

[aeric]

Using ZipToMap :

Private Sub GetB4XLibVersion (LibPath As String) As String
    Dim files As Map = ZipToMap(LibPath)
    Dim b() As Byte = files.Get("manifest.txt")
    Dim txt As String = BytesToString(b, 0, b.Length, "utf8")
    Dim lines() As String = Regex.Split(CRLF, txt)
    For Each line As String In lines
        If line.StartsWith("Version=") Then
            Return line.SubString(8)
        End If
    Next
    Return "Unknown"
End Sub

 

[aeric]

Sub GetB4XLibVersion (LibPath As String) As String
    Dim jZip As JavaObject
    jZip.InitializeNewInstance("java.util.zip.ZipFile", Array(LibPath))
    Dim ZipEntry As JavaObject = jZip.RunMethod("getEntry", Array("manifest.txt"))
    If ZipEntry.IsInitialized Then
        Dim jInputStream As JavaObject = jZip.RunMethod("getInputStream", Array(ZipEntry))
        Dim b() As Byte = Bit.InputStreamToBytes(jInputStream)
        Dim txt As String = BytesToString(b, 0, b.Length, "utf8")
        Dim lines() As String = Regex.Split(CRLF, txt)
        For Each line As String In lines
            If line.StartsWith("Version=") Then
                Return line.SubString(8) ' Extract version number
            End If
        Next
    End If
    Return "Unknown"
End Sub

 

[Erel]

Using ZipToMap :

If you only need to read the manifest file then it is more efficient to call UnzipEntry. No reason to unpack all files into memory.