https://freemarker.apache.org/: FreeMarker is a "template engine"; a generic tool to generate text output based on templates. (Apache Software Foundation) 
public class freemarker.core.OptInTemplateClassResolver implements freemarker.core.TemplateClassResolver
  minor version: 0
  major version: 59
  flags: flags: (0x0021) ACC_PUBLIC, ACC_SUPER
  this_class: freemarker.core.OptInTemplateClassResolver
  super_class: java.lang.Object
{
  private final java.util.Set allowedClasses;
    descriptor: Ljava/util/Set;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL

  private final java.util.List trustedTemplatePrefixes;
    descriptor: Ljava/util/List;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL

  private final java.util.Set trustedTemplateNames;
    descriptor: Ljava/util/Set;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL

  public void <init>(java.util.Set, java.util.List);
    descriptor: (Ljava/util/Set;Ljava/util/List;)V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=5, locals=5, args_size=3
        start local 0 // freemarker.core.OptInTemplateClassResolver this
        start local 1 // java.util.Set allowedClasses
        start local 2 // java.util.List trustedTemplates
         0: .line 68
            aload 0 /* this */
            invokespecial java.lang.Object.<init>:()V
         1: .line 70
            aload 0 /* this */
            aload 1 /* allowedClasses */
            ifnull 2
            aload 1 /* allowedClasses */
            goto 3
      StackMap locals: freemarker.core.OptInTemplateClassResolver java.util.Set java.util.List
      StackMap stack: freemarker.core.OptInTemplateClassResolver
         2: getstatic java.util.Collections.EMPTY_SET:Ljava/util/Set;
      StackMap locals: freemarker.core.OptInTemplateClassResolver java.util.Set java.util.List
      StackMap stack: freemarker.core.OptInTemplateClassResolver java.util.Set
         3: putfield freemarker.core.OptInTemplateClassResolver.allowedClasses:Ljava/util/Set;
         4: .line 71
            aload 2 /* trustedTemplates */
            ifnull 17
         5: .line 72
            aload 0 /* this */
            new java.util.HashSet
            dup
            invokespecial java.util.HashSet.<init>:()V
            putfield freemarker.core.OptInTemplateClassResolver.trustedTemplateNames:Ljava/util/Set;
         6: .line 73
            aload 0 /* this */
            new java.util.ArrayList
            dup
            invokespecial java.util.ArrayList.<init>:()V
            putfield freemarker.core.OptInTemplateClassResolver.trustedTemplatePrefixes:Ljava/util/List;
         7: .line 75
            aload 2 /* trustedTemplates */
            invokeinterface java.util.List.iterator:()Ljava/util/Iterator;
            astore 3 /* it */
        start local 3 // java.util.Iterator it
         8: .line 76
            goto 15
         9: .line 77
      StackMap locals: java.util.Iterator
      StackMap stack:
            aload 3 /* it */
            invokeinterface java.util.Iterator.next:()Ljava/lang/Object;
            checkcast java.lang.String
            astore 4 /* li */
        start local 4 // java.lang.String li
        10: .line 78
            aload 4 /* li */
            ldc "/"
            invokevirtual java.lang.String.startsWith:(Ljava/lang/String;)Z
            ifeq 11
            aload 4 /* li */
            iconst_1
            invokevirtual java.lang.String.substring:(I)Ljava/lang/String;
            astore 4 /* li */
        11: .line 79
      StackMap locals: java.lang.String
      StackMap stack:
            aload 4 /* li */
            ldc "*"
            invokevirtual java.lang.String.endsWith:(Ljava/lang/String;)Z
            ifeq 14
        12: .line 80
            aload 0 /* this */
            getfield freemarker.core.OptInTemplateClassResolver.trustedTemplatePrefixes:Ljava/util/List;
            aload 4 /* li */
            iconst_0
            aload 4 /* li */
            invokevirtual java.lang.String.length:()I
            iconst_1
            isub
            invokevirtual java.lang.String.substring:(II)Ljava/lang/String;
            invokeinterface java.util.List.add:(Ljava/lang/Object;)Z
            pop
        13: .line 81
            goto 15
        14: .line 82
      StackMap locals:
      StackMap stack:
            aload 0 /* this */
            getfield freemarker.core.OptInTemplateClassResolver.trustedTemplateNames:Ljava/util/Set;
            aload 4 /* li */
            invokeinterface java.util.Set.add:(Ljava/lang/Object;)Z
            pop
        end local 4 // java.lang.String li
        15: .line 76
      StackMap locals:
      StackMap stack:
            aload 3 /* it */
            invokeinterface java.util.Iterator.hasNext:()Z
            ifne 9
        end local 3 // java.util.Iterator it
        16: .line 85
            goto 19
        17: .line 86
      StackMap locals:
      StackMap stack:
            aload 0 /* this */
            getstatic java.util.Collections.EMPTY_SET:Ljava/util/Set;
            putfield freemarker.core.OptInTemplateClassResolver.trustedTemplateNames:Ljava/util/Set;
        18: .line 87
            aload 0 /* this */
            getstatic java.util.Collections.EMPTY_LIST:Ljava/util/List;
            putfield freemarker.core.OptInTemplateClassResolver.trustedTemplatePrefixes:Ljava/util/List;
        19: .line 89
      StackMap locals:
      StackMap stack:
            return
        end local 2 // java.util.List trustedTemplates
        end local 1 // java.util.Set allowedClasses
        end local 0 // freemarker.core.OptInTemplateClassResolver this
      LocalVariableTable:
        Start  End  Slot              Name  Signature
            0   20     0              this  Lfreemarker/core/OptInTemplateClassResolver;
            0   20     1    allowedClasses  Ljava/util/Set;
            0   20     2  trustedTemplates  Ljava/util/List;
            8   16     3                it  Ljava/util/Iterator;
           10   15     4                li  Ljava/lang/String;
    MethodParameters:
                  Name  Flags
      allowedClasses    
      trustedTemplates  

  public java.lang.Class resolve(java.lang.String, freemarker.core.Environment, freemarker.template.Template);
    descriptor: (Ljava/lang/String;Lfreemarker/core/Environment;Lfreemarker/template/Template;)Ljava/lang/Class;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=7, locals=6, args_size=4
        start local 0 // freemarker.core.OptInTemplateClassResolver this
        start local 1 // java.lang.String className
        start local 2 // freemarker.core.Environment env
        start local 3 // freemarker.template.Template template
         0: .line 93
            aload 0 /* this */
            aload 3 /* template */
            invokevirtual freemarker.core.OptInTemplateClassResolver.safeGetTemplateName:(Lfreemarker/template/Template;)Ljava/lang/String;
            astore 4 /* templateName */
        start local 4 // java.lang.String templateName
         1: .line 95
            aload 4 /* templateName */
            ifnull 5
         2: .line 96
            aload 0 /* this */
            getfield freemarker.core.OptInTemplateClassResolver.trustedTemplateNames:Ljava/util/Set;
            aload 4 /* templateName */
            invokeinterface java.util.Set.contains:(Ljava/lang/Object;)Z
            ifne 4
         3: .line 97
            aload 0 /* this */
            aload 4 /* templateName */
            invokevirtual freemarker.core.OptInTemplateClassResolver.hasMatchingPrefix:(Ljava/lang/String;)Z
            ifeq 5
         4: .line 98
      StackMap locals: java.lang.String
      StackMap stack:
            getstatic freemarker.core.TemplateClassResolver.SAFER_RESOLVER:Lfreemarker/core/TemplateClassResolver;
            aload 1 /* className */
            aload 2 /* env */
            aload 3 /* template */
            invokeinterface freemarker.core.TemplateClassResolver.resolve:(Ljava/lang/String;Lfreemarker/core/Environment;Lfreemarker/template/Template;)Ljava/lang/Class;
            areturn
         5: .line 100
      StackMap locals:
      StackMap stack:
            aload 0 /* this */
            getfield freemarker.core.OptInTemplateClassResolver.allowedClasses:Ljava/util/Set;
            aload 1 /* className */
            invokeinterface java.util.Set.contains:(Ljava/lang/Object;)Z
            ifne 11
         6: .line 101
            new freemarker.core._MiscTemplateException
            dup
            aload 2 /* env */
            iconst_5
            anewarray java.lang.Object
            dup
            iconst_0
         7: .line 102
            ldc "Instantiating "
            aastore
            dup
            iconst_1
            aload 1 /* className */
            aastore
            dup
            iconst_2
            ldc " is not allowed in the template for security reasons. (If you run into this problem when using ?new in a template, you may want to check the \""
            aastore
            dup
            iconst_3
         8: .line 104
            ldc "new_builtin_class_resolver"
            aastore
            dup
            iconst_4
         9: .line 105
            ldc "\" setting in the FreeMarker configuration.)"
        10: .line 101
            aastore
            invokespecial freemarker.core._MiscTemplateException.<init>:(Lfreemarker/core/Environment;[Ljava/lang/Object;)V
            athrow
        11: .line 108
      StackMap locals:
      StackMap stack:
            aload 1 /* className */
            invokestatic freemarker.template.utility.ClassUtil.forName:(Ljava/lang/String;)Ljava/lang/Class;
        12: areturn
        13: .line 109
      StackMap locals:
      StackMap stack: java.lang.ClassNotFoundException
            astore 5 /* e */
        start local 5 // java.lang.ClassNotFoundException e
        14: .line 110
            new freemarker.core._MiscTemplateException
            dup
            aload 5 /* e */
            aload 2 /* env */
            invokespecial freemarker.core._MiscTemplateException.<init>:(Ljava/lang/Throwable;Lfreemarker/core/Environment;)V
            athrow
        end local 5 // java.lang.ClassNotFoundException e
        end local 4 // java.lang.String templateName
        end local 3 // freemarker.template.Template template
        end local 2 // freemarker.core.Environment env
        end local 1 // java.lang.String className
        end local 0 // freemarker.core.OptInTemplateClassResolver this
      LocalVariableTable:
        Start  End  Slot          Name  Signature
            0   15     0          this  Lfreemarker/core/OptInTemplateClassResolver;
            0   15     1     className  Ljava/lang/String;
            0   15     2           env  Lfreemarker/core/Environment;
            0   15     3      template  Lfreemarker/template/Template;
            1   15     4  templateName  Ljava/lang/String;
           14   15     5             e  Ljava/lang/ClassNotFoundException;
      Exception table:
        from    to  target  type
          11    12      13  Class java.lang.ClassNotFoundException
    Exceptions:
      throws freemarker.template.TemplateException
    MethodParameters:
           Name  Flags
      className  
      env        
      template   

  protected java.lang.String safeGetTemplateName(freemarker.template.Template);
    descriptor: (Lfreemarker/template/Template;)Ljava/lang/String;
    flags: (0x0004) ACC_PROTECTED
    Code:
      stack=5, locals=7, args_size=2
        start local 0 // freemarker.core.OptInTemplateClassResolver this
        start local 1 // freemarker.template.Template template
         0: .line 121
            aload 1 /* template */
            ifnonnull 1
            aconst_null
            areturn
         1: .line 123
      StackMap locals:
      StackMap stack:
            aload 1 /* template */
            invokevirtual freemarker.template.Template.getName:()Ljava/lang/String;
            astore 2 /* name */
        start local 2 // java.lang.String name
         2: .line 124
            aload 2 /* name */
            ifnonnull 3
            aconst_null
            areturn
         3: .line 127
      StackMap locals: java.lang.String
      StackMap stack:
            aload 2 /* name */
            astore 3 /* decodedName */
        start local 3 // java.lang.String decodedName
         4: .line 128
            aload 3 /* decodedName */
            bipush 37
            invokevirtual java.lang.String.indexOf:(I)I
            iconst_m1
            if_icmpeq 11
         5: .line 129
            aload 3 /* decodedName */
            ldc "%2e"
            ldc "."
            iconst_0
            iconst_0
            invokestatic freemarker.template.utility.StringUtil.replace:(Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;ZZ)Ljava/lang/String;
            astore 3 /* decodedName */
         6: .line 130
            aload 3 /* decodedName */
            ldc "%2E"
            ldc "."
            iconst_0
            iconst_0
            invokestatic freemarker.template.utility.StringUtil.replace:(Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;ZZ)Ljava/lang/String;
            astore 3 /* decodedName */
         7: .line 131
            aload 3 /* decodedName */
            ldc "%2f"
            ldc "/"
            iconst_0
            iconst_0
            invokestatic freemarker.template.utility.StringUtil.replace:(Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;ZZ)Ljava/lang/String;
            astore 3 /* decodedName */
         8: .line 132
            aload 3 /* decodedName */
            ldc "%2F"
            ldc "/"
            iconst_0
            iconst_0
            invokestatic freemarker.template.utility.StringUtil.replace:(Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;ZZ)Ljava/lang/String;
            astore 3 /* decodedName */
         9: .line 133
            aload 3 /* decodedName */
            ldc "%5c"
            ldc "\\"
            iconst_0
            iconst_0
            invokestatic freemarker.template.utility.StringUtil.replace:(Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;ZZ)Ljava/lang/String;
            astore 3 /* decodedName */
        10: .line 134
            aload 3 /* decodedName */
            ldc "%5C"
            ldc "\\"
            iconst_0
            iconst_0
            invokestatic freemarker.template.utility.StringUtil.replace:(Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;ZZ)Ljava/lang/String;
            astore 3 /* decodedName */
        11: .line 136
      StackMap locals: java.lang.String
      StackMap stack:
            aload 3 /* decodedName */
            ldc ".."
            invokevirtual java.lang.String.indexOf:(Ljava/lang/String;)I
            istore 4 /* dotDotIdx */
        start local 4 // int dotDotIdx
        12: .line 137
            iload 4 /* dotDotIdx */
            iconst_m1
            if_icmpeq 22
        13: .line 138
            iload 4 /* dotDotIdx */
            iconst_1
            isub
            iflt 14
            aload 3 /* decodedName */
            iload 4 /* dotDotIdx */
            iconst_1
            isub
            invokevirtual java.lang.String.charAt:(I)C
            goto 15
      StackMap locals: int
      StackMap stack:
        14: iconst_m1
      StackMap locals:
      StackMap stack: int
        15: istore 5 /* before */
        start local 5 // int before
        16: .line 139
            iload 4 /* dotDotIdx */
            iconst_2
            iadd
            aload 3 /* decodedName */
            invokevirtual java.lang.String.length:()I
            if_icmpge 17
            aload 3 /* decodedName */
            iload 4 /* dotDotIdx */
            iconst_2
            iadd
            invokevirtual java.lang.String.charAt:(I)C
            goto 18
      StackMap locals: int
      StackMap stack:
        17: iconst_m1
      StackMap locals:
      StackMap stack: int
        18: istore 6 /* after */
        start local 6 // int after
        19: .line 140
            iload 5 /* before */
            iconst_m1
            if_icmpeq 20
            iload 5 /* before */
            bipush 47
            if_icmpeq 20
            iload 5 /* before */
            bipush 92
            if_icmpne 22
        20: .line 141
      StackMap locals: int
      StackMap stack:
            iload 6 /* after */
            iconst_m1
            if_icmpeq 21
            iload 6 /* after */
            bipush 47
            if_icmpeq 21
            iload 6 /* after */
            bipush 92
            if_icmpne 22
        21: .line 142
      StackMap locals:
      StackMap stack:
            aconst_null
            areturn
        end local 6 // int after
        end local 5 // int before
        22: .line 146
      StackMap locals:
      StackMap stack:
            aload 2 /* name */
            ldc "/"
            invokevirtual java.lang.String.startsWith:(Ljava/lang/String;)Z
            ifeq 23
            aload 2 /* name */
            iconst_1
            invokevirtual java.lang.String.substring:(I)Ljava/lang/String;
            goto 24
      StackMap locals:
      StackMap stack:
        23: aload 2 /* name */
      StackMap locals:
      StackMap stack: java.lang.String
        24: areturn
        end local 4 // int dotDotIdx
        end local 3 // java.lang.String decodedName
        end local 2 // java.lang.String name
        end local 1 // freemarker.template.Template template
        end local 0 // freemarker.core.OptInTemplateClassResolver this
      LocalVariableTable:
        Start  End  Slot         Name  Signature
            0   25     0         this  Lfreemarker/core/OptInTemplateClassResolver;
            0   25     1     template  Lfreemarker/template/Template;
            2   25     2         name  Ljava/lang/String;
            4   25     3  decodedName  Ljava/lang/String;
           12   25     4    dotDotIdx  I
           16   22     5       before  I
           19   22     6        after  I
    MethodParameters:
          Name  Flags
      template  

  private boolean hasMatchingPrefix(java.lang.String);
    descriptor: (Ljava/lang/String;)Z
    flags: (0x0002) ACC_PRIVATE
    Code:
      stack=2, locals=4, args_size=2
        start local 0 // freemarker.core.OptInTemplateClassResolver this
        start local 1 // java.lang.String name
         0: .line 150
            iconst_0
            istore 2 /* i */
        start local 2 // int i
         1: goto 5
         2: .line 151
      StackMap locals: int
      StackMap stack:
            aload 0 /* this */
            getfield freemarker.core.OptInTemplateClassResolver.trustedTemplatePrefixes:Ljava/util/List;
            iload 2 /* i */
            invokeinterface java.util.List.get:(I)Ljava/lang/Object;
            checkcast java.lang.String
            astore 3 /* prefix */
        start local 3 // java.lang.String prefix
         3: .line 152
            aload 1 /* name */
            aload 3 /* prefix */
            invokevirtual java.lang.String.startsWith:(Ljava/lang/String;)Z
            ifeq 4
            iconst_1
            ireturn
        end local 3 // java.lang.String prefix
         4: .line 150
      StackMap locals:
      StackMap stack:
            iinc 2 /* i */ 1
      StackMap locals:
      StackMap stack:
         5: iload 2 /* i */
            aload 0 /* this */
            getfield freemarker.core.OptInTemplateClassResolver.trustedTemplatePrefixes:Ljava/util/List;
            invokeinterface java.util.List.size:()I
            if_icmplt 2
        end local 2 // int i
         6: .line 154
            iconst_0
            ireturn
        end local 1 // java.lang.String name
        end local 0 // freemarker.core.OptInTemplateClassResolver this
      LocalVariableTable:
        Start  End  Slot    Name  Signature
            0    7     0    this  Lfreemarker/core/OptInTemplateClassResolver;
            0    7     1    name  Ljava/lang/String;
            1    6     2       i  I
            3    4     3  prefix  Ljava/lang/String;
    MethodParameters:
      Name  Flags
      name  
}
SourceFile: "OptInTemplateClassResolver.java"