Forge isn't working for 1.14.4. I'm not entirely sure why.
I have tried deleting Minecraft and reinstalling and downloading the latest version of Java.
See logs below. Thanks for your help:
JVM info: Oracle Corporation - 1.8.0_221 - 25.221-b11
java.net.preferIPv4Stack=true
Found java version 1.8.0_221
Extracting json
Considering minecraft client jar
Downloading libraries
Considering library net.minecraftforge:forge:1.14.4-28.1.0
File exists: Checksum validated.
Considering library org.ow2.asm:asm:6.2
File exists: Checksum validated.
Considering library org.ow2.asm:asm-commons:6.2
File exists: Checksum validated.
Considering library org.ow2.asm:asm-tree:6.2
File exists: Checksum validated.
Considering library cpw.mods:modlauncher:3.2.0
File exists: Checksum validated.
Considering library cpw.mods:grossjava9hacks:1.1.0
File exists: Checksum validated.
Considering library net.minecraftforge:accesstransformers:1.0.0-shadowed
File exists: Checksum validated.
Considering library net.minecraftforge:eventbus:1.0.0-service
File exists: Checksum validated.
Considering library net.minecraftforge:forgespi:1.3.0
File exists: Checksum validated.
Considering library net.minecraftforge:coremods:1.0.0
File exists: Checksum validated.
Considering library net.minecraftforge:unsafe:0.2.0
File exists: Checksum validated.
Considering library com.electronwill.night-config:core:3.6.0
File exists: Checksum validated.
Considering library com.electronwill.night-config:toml:3.6.0
File exists: Checksum validated.
Considering library org.jline:jline:3.12.1
File exists: Checksum validated.
Considering library org.apache.maven:maven-artifact:3.6.0
File exists: Checksum validated.
Considering library net.jodah:typetools:0.6.0
File exists: Checksum validated.
Considering library java3d:vecmath:1.5.2
File exists: Checksum validated.
Considering library org.apache.logging.log4j:log4j-api:2.11.2
File exists: Checksum validated.
Considering library org.apache.logging.log4j:log4j-core:2.11.2
File exists: Checksum validated.
Considering library net.minecrell:terminalconsoleappender:1.2.0
File exists: Checksum validated.
Considering library net.sf.jopt-simple:jopt-simple:5.0.4
File exists: Checksum validated.
Considering library com.github.jponge:lzma-java:1.3
File exists: Checksum validated.
Considering library com.google.code.findbugs:jsr305:3.0.2
File exists: Checksum validated.
Considering library com.google.code.gson:gson:2.8.0
File exists: Checksum validated.
Considering library com.google.errorprone:error_prone_annotations:2.1.3
File exists: Checksum validated.
Considering library com.google.guava:guava:20.0
File exists: Checksum validated.
Considering library com.google.guava:guava:25.1-jre
File exists: Checksum validated.
Considering library com.google.j2objc:j2objc-annotations:1.1
File exists: Checksum validated.
Considering library com.nothome:javaxdelta:2.0.1
File exists: Checksum validated.
Considering library commons-io:commons-io:2.4
File exists: Checksum validated.
Considering library de.oceanlabs.mcp:mcp_config:1.14.4-20190829.143755@zip
File exists: Checksum validated.
Considering library net.md-5:SpecialSource:1.8.5
File exists: Checksum validated.
Considering library net.minecraftforge:binarypatcher:1.0.5
File exists: Checksum validated.
Considering library net.minecraftforge:forge:1.14.4-28.1.0:universal
File exists: Checksum validated.
Considering library net.minecraftforge:installertools:1.1.4
File exists: Checksum validated.
Considering library net.minecraftforge:jarsplitter:1.1.0
File exists: Checksum validated.
Considering library net.sf.jopt-simple:jopt-simple:4.9
File exists: Checksum validated.
Considering library net.sf.jopt-simple:jopt-simple:5.0.4
File exists: Checksum validated.
Considering library net.sf.opencsv:opencsv:2.3
File exists: Checksum validated.
Considering library org.checkerframework:checker-qual:2.0.0
File exists: Checksum validated.
Considering library org.codehaus.mojo:animal-sniffer-annotations:1.14
File exists: Checksum validated.
Considering library org.ow2.asm:asm-analysis:6.1.1
File exists: Checksum validated.
Considering library org.ow2.asm:asm-commons:6.1.1
File exists: Checksum validated.
Considering library org.ow2.asm:asm-tree:6.1.1
File exists: Checksum validated.
Considering library org.ow2.asm:asm:6.1.1
File exists: Checksum validated.
Considering library trove:trove:1.0.2
File exists: Checksum validated.
Created Temporary Directory: /var/folders/5c/_zgpm61s3mg7xwmx41qgmqwc0000gn/T/forge_installer4454779904270912949
Extracting: /data/client.lzma
Building Processors
===============================================================================
MainClass: net.minecraftforge.installertools.ConsoleTool
Classpath:
/Users/user/Library/Application Support/minecraft/libraries/net/minecraftforge/installertools/1.1.4/installertools-1.1.4.jar
/Users/user/Library/Application Support/minecraft/libraries/net/md-5/SpecialSource/1.8.5/SpecialSource-1.8.5.jar
/Users/user/Library/Application Support/minecraft/libraries/net/sf/jopt-simple/jopt-simple/5.0.4/jopt-simple-5.0.4.jar
/Users/user/Library/Application Support/minecraft/libraries/com/google/code/gson/gson/2.8.0/gson-2.8.0.jar
/Users/user/Library/Application Support/minecraft/libraries/org/ow2/asm/asm-commons/6.1.1/asm-commons-6.1.1.jar
/Users/user/Library/Application Support/minecraft/libraries/com/google/guava/guava/20.0/guava-20.0.jar
/Users/user/Library/Application Support/minecraft/libraries/net/sf/opencsv/opencsv/2.3/opencsv-2.3.jar
/Users/user/Library/Application Support/minecraft/libraries/org/ow2/asm/asm-analysis/6.1.1/asm-analysis-6.1.1.jar
/Users/user/Library/Application Support/minecraft/libraries/org/ow2/asm/asm-tree/6.1.1/asm-tree-6.1.1.jar
/Users/user/Library/Application Support/minecraft/libraries/org/ow2/asm/asm/6.1.1/asm-6.1.1.jar
Args: --task, MCP_DATA, --input, "/Users/user/Library/Application Support/minecraft/libraries/de/oceanlabs/mcp/mcp_config/1.14.4-20190829.143755/mcp_config-1.14.4-20190829.143755.zip", --output, "/Users/user/Library/Application Support/minecraft/libraries/de/oceanlabs/mcp/mcp_config/1.14.4-20190829.143755/mcp_config-1.14.4-20190829.143755-mappings.txt", --key, mappings
Task: MCP_DATA
Input: /Users/user/Library/Application Support/minecraft/libraries/de/oceanlabs/mcp/mcp_config/1.14.4-20190829.143755/mcp_config-1.14.4-20190829.143755.zip
Output: /Users/user/Library/Application Support/minecraft/libraries/de/oceanlabs/mcp/mcp_config/1.14.4-20190829.143755/mcp_config-1.14.4-20190829.143755-mappings.txt
Key: mappings
Extracting: config/joined.tsrg
===============================================================================
Cache:
/Users/user/Library/Application Support/minecraft/libraries/net/minecraft/client/1.14.4/client-1.14.4-slim.jar
Expected: db1f32cac159af8a5fb4e805e6c2b880388782a5
Actual: 657d452f789b39170d9c2b9fa26da64b05feca67
/Users/user/Library/Application Support/minecraft/libraries/net/minecraft/client/1.14.4/client-1.14.4-extra.jar
Expected: 4ccc85c80f9ed2827c8351c3aff29a12df6f7951
Actual: 00722d8854a48533e3ecd5714eb4d1783fc70500
MainClass: net.minecraftforge.jarsplitter.ConsoleTool
Classpath:
/Users/user/Library/Application Support/minecraft/libraries/net/minecraftforge/jarsplitter/1.1.0/jarsplitter-1.1.0.jar
/Users/user/Library/Application Support/minecraft/libraries/net/sf/jopt-simple/jopt-simple/5.0.4/jopt-simple-5.0.4.jar
Args: --input, "/Users/user/Library/Application Support/minecraft/versions/1.14.4/1.14.4.jar", --slim, "/Users/user/Library/Application Support/minecraft/libraries/net/minecraft/client/1.14.4/client-1.14.4-slim.jar", --extra, "/Users/user/Library/Application Support/minecraft/libraries/net/minecraft/client/1.14.4/client-1.14.4-extra.jar", --srg, "/Users/user/Library/Application Support/minecraft/libraries/de/oceanlabs/mcp/mcp_config/1.14.4-20190829.143755/mcp_config-1.14.4-20190829.143755-mappings.txt"
Splitter:
Input: /Users/user/Library/Application Support/minecraft/versions/1.14.4/1.14.4.jar
Input: /Users/user/Library/Application Support/minecraft/versions/1.14.4/1.14.4.jar
Slim: /Users/user/Library/Application Support/minecraft/libraries/net/minecraft/client/1.14.4/client-1.14.4-slim.jar
Data: null
Extra: /Users/user/Library/Application Support/minecraft/libraries/net/minecraft/client/1.14.4/client-1.14.4-extra.jar
Including data in extra
SRG: /Users/user/Library/Application Support/minecraft/libraries/de/oceanlabs/mcp/mcp_config/1.14.4-20190829.143755/mcp_config-1.14.4-20190829.143755-mappings.txt
InputSha: 2be30c9b8bc74b2956ce5f02c4e16a6499accffa
SrgSha: e5e84c8167a9deac3815da8706009d66bf0b58de
Splitting:
Data META-INF/MANIFEST.MF
Data META-INF/MOJANGCS.SF
Data META-INF/MOJANGCS.RSA
Slim net/minecraft/realms/RealmsEditBox.class
Slim net/minecraft/realms/DisconnectedRealmsScreen.class
Slim net/minecraft/realms/RealmsVertexFormatElement.class
Slim net/minecraft/realms/RealmsObjectSelectionList.class
Slim net/minecraft/realms/pluginapi/RealmsPlugin.class
Slim net/minecraft/realms/pluginapi/LoadedRealmsPlugin.class
Slim net/minecraft/realms/RealmsAbstractButtonProxy.class
Slim net/minecraft/realms/RealmsMth.class
Slim net/minecraft/realms/RepeatedNarrator$a.class
Slim net/minecraft/realms/RealmListEntry.class
Slim net/minecraft/realms/RealmsBufferBuilder.class
Slim net/minecraft/realms/RealmsSliderButton.class
Slim net/minecraft/realms/RealmsDefaultVertexFormat.class
Slim net/minecraft/realms/RealmsSliderButtonProxy.class
Slim net/minecraft/realms/RealmsLabelProxy.class
Slim net/minecraft/realms/RealmsClickableScrolledSelectionList.class
Slim net/minecraft/realms/RealmsConnect$1.class
Slim net/minecraft/realms/RealmsScrolledSelectionList.class
Slim net/minecraft/realms/RealmsConfirmResultListener.class
Slim net/minecraft/realms/RepeatedNarrator.class
Slim net/minecraft/realms/DisconnectedRealmsScreen$1.class
Slim net/minecraft/realms/RealmsBridge.class
Slim net/minecraft/realms/RealmsScrolledSelectionListProxy.class
Slim net/minecraft/realms/AbstractRealmsButton.class
Slim net/minecraft/realms/RealmsLabel.class
Slim net/minecraft/realms/RealmsLevelSummary.class
Slim net/minecraft/realms/RealmsServerAddress.class
Slim net/minecraft/realms/RealmsSimpleScrolledSelectionListProxy.class
Slim net/minecraft/realms/Realms.class
Slim net/minecraft/realms/RealmsConnect.class
Slim net/minecraft/realms/Tezzelator.class
Slim net/minecraft/realms/RealmsButtonProxy.class
Slim net/minecraft/realms/RealmsClickableScrolledSelectionListProxy.class
Slim net/minecraft/realms/RealmsVertexFormat.class
Slim net/minecraft/realms/RealmsScreenProxy.class
Slim net/minecraft/realms/RealmsSharedConstants.class
Slim net/minecraft/realms/RealmsObjectSelectionListProxy.class
Slim net/minecraft/realms/RealmsGuiEventListener.class
Slim net/minecraft/realms/RealmsSimpleScrolledSelectionList.class
Slim net/minecraft/realms/RealmsButton.class
Slim net/minecraft/realms/RealmsAnvilLevelStorageSource.class
Slim net/minecraft/realms/RealmsScreen.class
Slim cyg$1.class
Slim cyc.class
Slim dka$1.class
Slim dkb.class
Slim dkk.class
Slim dki$a.class
Slim djz$a.class
Slim dka$a.class
Slim dke.class
Slim dkh.class
Slim dkk$1.class
Slim dkc.class
Slim dkg.class
Slim dkj.class
Slim dka.class
Slim dkc$1.class
Slim dki.class
Slim dkg$1.class
Slim dkf.class
Slim djz.class
Slim dkk$2$1.class
Slim dkk$2.class
Slim dkd.class
Slim cxn.class
Slim cyf.class
Slim dzx$a.class
Slim dzv.class
Slim dzz$1.class
Slim dzy.class
Slim dzu.class
Slim dzw.class
Slim dzx.class
Slim dzv$a.class
Slim dzw$a.class
Slim dzz.class
Slim cyh.class
Slim eav.class
Slim eba.class
Slim eaw.class
Slim eaz.class
Slim eat.class
Slim eay.class
Slim ebb.class
Slim eax.class
Slim eau.class
Slim cyu$a.class
Slim czb.class
Slim cyz.class
Slim cyy.class
Slim cza.class
Slim cyx$a.class
Slim dat.class
Slim dar.class
Slim dbe.class
Slim dba$1.class
Slim dbb.class
Slim dbd$a.class
Slim dbd.class
Slim dba.class
Slim dbd$b.class
Slim dbc.class
Slim dba$b.class
Slim dba$a.class
Slim dbd$1.class
Slim dau.class
Slim dat$a.class
Failed to run processor: java.io.EOFException:Unexpected end of ZLIB input stream
See log for more details.