LuaNil (encryption-tools 1.0.0 API)

java.lang.Object
- org.luaj.vm2.Varargs
- - org.luaj.vm2.LuaValue
  - - org.luaj.vm2.LuaNil

```
public class LuaNil
extends LuaValue
```
Class to encapsulate behavior of the singleton instance nil
There will be one instance of this class, LuaValue.NIL, per Java virtual machine. However, the Varargs instance LuaValue.NONE which is the empty list, is also considered treated as a nil value by default.
Although it is possible to test for nil using Java == operator, the recommended approach is to use the method LuaValue.isnil() instead. By using that any ambiguities between LuaValue.NIL and LuaValue.NONE are avoided.

另请参阅:

LuaValue, LuaValue.NIL

字段概要

字段
限定符和类型字段和说明

static LuaValue s_metatable
- 从类继承的字段 org.luaj.vm2.LuaValue
  ADD, BAND, BNOT, BOR, BXOR, CALL, CONCAT, DIV, EMPTYSTRING, ENV, EQ, FALSE, IDIV, INDEX, LE, LEN, LT, METATABLE, MINUSONE, MOD, MODE, MUL, NEWINDEX, NIL, NILS, NONE, NOVALS, ONE, POW, SHL, SHR, SUB, TBOOLEAN, TFUNCTION, TINT, TLIGHTUSERDATA, TNIL, TNONE, TNUMBER, TOSTRING, TRUE, TSTRING, TTABLE, TTHREAD, TUSERDATA, TVALUE, TYPE_NAMES, UNM, uservalue, ZERO

字段
限定符和类型	字段和说明
`static LuaValue`	`s_metatable`

方法概要

所有方法实例方法具体方法
限定符和类型	方法和说明
`LuaValue`	`checknotnil()` Check that this is not the value `LuaValue.NIL`, or throw `LuaError` if it is
`boolean`	`equals(Object o)`
`LuaValue`	`getmetatable()` Get the metatable for this `LuaValue` For `LuaTable` and `LuaUserdata` instances, the metatable returned is this instance metatable.
`boolean`	`isnil()` Check if `this` is `#NIL`
`boolean`	`isvalidkey()` Return true if this is a valid key in a table index operation.
`LuaValue`	`not()` Unary not: return inverse boolean value `(~this)` as defined by lua not operator
`boolean`	`optboolean(boolean defval)` Check that optional argument is a boolean and return its boolean value
`LuaClosure`	`optclosure(LuaClosure defval)` Check that optional argument is a closure and return as `LuaClosure` A `LuaClosure` is a `LuaFunction` that executes lua byteccode.
`double`	`optdouble(double defval)` Check that optional argument is a number or string convertible to number and return as double
`LuaFunction`	`optfunction(LuaFunction defval)` Check that optional argument is a function and return as `LuaFunction` A `LuaFunction` may either be a Java function that implements functionality directly in Java, or a `LuaClosure` which is a `LuaFunction` that executes lua bytecode.
`int`	`optint(int defval)` Check that optional argument is a number or string convertible to number and return as int
`LuaInteger`	`optinteger(LuaInteger defval)` Check that optional argument is a number or string convertible to number and return as `LuaInteger`
`String`	`optjstring(String defval)` Check that optional argument is a string or number and return as Java String
`long`	`optlong(long defval)` Check that optional argument is a number or string convertible to number and return as long
`LuaNumber`	`optnumber(LuaNumber defval)` Check that optional argument is a number or string convertible to number and return as `LuaNumber`
`LuaString`	`optstring(LuaString defval)` Check that optional argument is a string or number and return as `LuaString`
`LuaTable`	`opttable(LuaTable defval)` Check that optional argument is a table and return as `LuaTable`
`LuaThread`	`optthread(LuaThread defval)` Check that optional argument is a thread and return as `LuaThread`
`Object`	`optuserdata(Class c, Object defval)` Check that optional argument is a userdata whose instance is of a type and return the Object instance
`Object`	`optuserdata(Object defval)` Check that optional argument is a userdata and return the Object instance
`LuaValue`	`optvalue(LuaValue defval)` Perform argument check that this is not nil or none.
`boolean`	`toboolean()` Convert to boolean false if `LuaValue.NIL` or `LuaValue.FALSE`, true if anything else
`String`	`tojstring()` Convert to human readable String for any type.
`String`	`toString()` Convert the value to a human readable string using `LuaValue.tojstring()`
`int`	`type()` Get the enumeration value for the type of this value.
`String`	`typename()` Get the String name of the type of this value.

从类继承的方法 org.luaj.vm2.LuaValue
add, add, add, and, arg, arg1, argerror, argerror, aritherror, aritherror, arithmt, arithmtwith, assert_, band, band, bnot, bor, bor, buffer, bxor, bxor, call, call, call, call, call, callmt, checkboolean, checkclosure, checkdouble, checkfunction, checkglobals, checkint, checkinteger, checkjstring, checklong, checkmetatag, checknumber, checknumber, checkstring, checktable, checkthread, checkuserdata, checkuserdata, compareerror, compareerror, comparemt, concat, concat, concatmt, concatTo, concatTo, concatTo, div, div, div, divInto, eq_b, eq, eqmtcall, error, get, get, get, getfenv, gettable, getuservalue, gt_b, gt_b, gt_b, gt, gt, gt, gteq_b, gteq_b, gteq_b, gteq, gteq, gteq, idiv, idiv, illegal, inext, initupvalue1, invoke, invoke, invoke, invoke, invoke, invoke, invokemethod, invokemethod, invokemethod, invokemethod, invokemethod, invokemethod, isboolean, isclosure, isfunction, isint, isinttype, islong, isnumber, isstring, istable, isthread, isuserdata, isuserdata, jcall, jget, jset, len, lenerror, length, listOf, listOf, load, lt_b, lt_b, lt_b, lt, lt, lt, lteq_b, lteq_b, lteq_b, lteq, lteq, lteq, metatableOf, metatag, method, method, method, method, method, method, mod, mod, mod, modFrom, mul, mul, mul, narg, neg, neq_b, neq, next, onInvoke, or, pow, pow, pow, powWith, powWith, presize, raweq, raweq, raweq, raweq, raweq, rawget, rawget, rawget, rawlen, rawset, rawset, rawset, rawset, rawset, rawset, rawset, rawsetlist, set, set, set, set, set, set, set, setfenv, setmetatable, settable, setuservalue, shl, shl, shr, shr, strcmp, strcmp, strongvalue, strvalue, sub, sub, sub, subargs, subFrom, subFrom, tableOf, tableOf, tableOf, tableOf, tableOf, tableOf, tailcallOf, testfor_b, tobyte, tochar, todouble, tofloat, toint, tolong, tonumber, toshort, tostring, touserdata, touserdata, typerror, unimplemented, userdataOf, userdataOf, valueOf, valueOf, valueOf, valueOf, valueOf, valueOf, valueOf, varargsOf, varargsOf, varargsOf, varargsOf, varargsOf, varargsOf

从类继承的方法 org.luaj.vm2.Varargs
argcheck, checkboolean, checkclosure, checkdouble, checkfunction, checkint, checkinteger, checkjstring, checklong, checknotnil, checknumber, checkstring, checktable, checkthread, checkuserdata, checkuserdata, checkvalue, dealias, eval, isfunction, isnil, isnoneornil, isnumber, isstring, istable, isTailcall, isthread, isuserdata, isvalue, optboolean, optclosure, optdouble, optfunction, optint, optinteger, optjstring, optlong, optnumber, optstring, opttable, optthread, optuserdata, optuserdata, optvalue, toboolean, tobyte, tochar, todouble, tofloat, toint, tojstring, tolong, toshort, touserdata, touserdata, type

从类继承的方法 java.lang.Object
clone, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- 字段详细资料
  - s_metatable
```
public static LuaValue s_metatable
```
- 方法详细资料
  - type
```
public int type()
```
    从类复制的说明: LuaValue
    
    Get the enumeration value for the type of this value.
    
    指定者:
    
    type 在类中 LuaValue
    
    返回:
    
    value for this type, one of LuaValue.TNIL, LuaValue.TBOOLEAN, LuaValue.TNUMBER, LuaValue.TSTRING, LuaValue.TTABLE, LuaValue.TFUNCTION, LuaValue.TUSERDATA, LuaValue.TTHREAD
    
    另请参阅:
    
    LuaValue.typename()
  - toString
```
public String toString()
```
    从类复制的说明: LuaValue
    
    Convert the value to a human readable string using LuaValue.tojstring()
    
    覆盖:
    
    toString 在类中 LuaValue
    
    返回:
    
    String value intended to be human readible.
    
    另请参阅:
    
    LuaValue.tostring(), LuaValue.tojstring(), LuaValue.optstring(LuaString), LuaValue.checkstring(), LuaValue.toString()
  - typename
```
public String typename()
```
    从类复制的说明: LuaValue
    
    Get the String name of the type of this value.
    
    指定者:
    
    typename 在类中 LuaValue
    
    返回:
    
    name from type name list LuaValue.TYPE_NAMES corresponding to the type of this value: "nil", "boolean", "number", "string", "table", "function", "userdata", "thread"
    
    另请参阅:
    
    LuaValue.type()
  - tojstring
```
public String tojstring()
```
    从类复制的说明: LuaValue
    
    Convert to human readable String for any type.
    
    覆盖:
    
    tojstring 在类中 LuaValue
    
    返回:
    
    String for use by human readers based on type.
    
    另请参阅:
    
    LuaValue.tostring(), LuaValue.optjstring(String), LuaValue.checkjstring(), LuaValue.isstring(), LuaValue.TSTRING
  - not
```
public LuaValue not()
```
    从类复制的说明: LuaValue
    
    Unary not: return inverse boolean value (~this) as defined by lua not operator
    
    覆盖:
    
    not 在类中 LuaValue
    
    返回:
    
    LuaValue.TRUE if LuaValue.NIL or LuaValue.FALSE, otherwise LuaValue.FALSE
  - toboolean
```
public boolean toboolean()
```
    从类复制的说明: LuaValue
    
    Convert to boolean false if LuaValue.NIL or LuaValue.FALSE, true if anything else
    
    覆盖:
    
    toboolean 在类中 LuaValue
    
    返回:
    
    Value cast to byte if number or string convertible to number, otherwise 0
    
    另请参阅:
    
    LuaValue.optboolean(boolean), LuaValue.checkboolean(), LuaValue.isboolean(), LuaValue.TBOOLEAN
  - isnil
```
public boolean isnil()
```
    从类复制的说明: LuaValue
    
    Check if this is #NIL
    
    覆盖:
    
    isnil 在类中 LuaValue
    
    返回:
    
    true if this is #NIL, otherwise false
    
    另请参阅:
    
    LuaValue.NIL, LuaValue.NONE, LuaValue.checknotnil(), LuaValue.optvalue(LuaValue), Varargs.isnoneornil(int), LuaValue.TNIL, LuaValue.TNONE
  - getmetatable
```
public LuaValue getmetatable()
```
    从类复制的说明: LuaValue
    
    Get the metatable for this LuaValue
    For LuaTable and LuaUserdata instances, the metatable returned is this instance metatable. For all other types, the class metatable value will be returned.
    
    覆盖:
    
    getmetatable 在类中 LuaValue
    
    返回:
    
    metatable, or null if it there is none
    
    另请参阅:
    
    LuaBoolean.s_metatable, LuaNumber.s_metatable, s_metatable, LuaFunction.s_metatable, LuaThread.s_metatable
  - equals
```
public boolean equals(Object o)
```
    覆盖:
    
    equals 在类中 LuaValue
  - checknotnil
```
public LuaValue checknotnil()
```
    从类复制的说明: LuaValue
    
    Check that this is not the value LuaValue.NIL, or throw LuaError if it is
    
    覆盖:
    
    checknotnil 在类中 LuaValue
    
    返回:
    
    this if it is not LuaValue.NIL
    
    另请参阅:
    
    LuaValue.optvalue(LuaValue)
  - isvalidkey
```
public boolean isvalidkey()
```
    从类复制的说明: LuaValue
    
    Return true if this is a valid key in a table index operation.
    
    覆盖:
    
    isvalidkey 在类中 LuaValue
    
    返回:
    
    true if valid as a table key, otherwise false
    
    另请参阅:
    
    LuaValue.isnil(), LuaValue.isinttype()
  - optboolean
```
public boolean optboolean(boolean defval)
```
    从类复制的说明: LuaValue
    
    Check that optional argument is a boolean and return its boolean value
    
    覆盖:
    
    optboolean 在类中 LuaValue
    
    参数:
    
    defval - boolean value to return if this is nil or none
    
    返回:
    
    this cast to boolean if a LuaBoolean, defval if nil or none, throws LuaError otherwise
    
    另请参阅:
    
    LuaValue.checkboolean(), LuaValue.isboolean(), LuaValue.TBOOLEAN
  - optclosure
```
public LuaClosure optclosure(LuaClosure defval)
```
    从类复制的说明: LuaValue
    
    Check that optional argument is a closure and return as LuaClosure
    A LuaClosure is a LuaFunction that executes lua byteccode.
    
    覆盖:
    
    optclosure 在类中 LuaValue
    
    参数:
    
    defval - LuaClosure to return if this is nil or none
    
    返回:
    
    this cast to LuaClosure if a function, defval if nil or none, throws LuaError otherwise
    
    另请参阅:
    
    LuaValue.checkclosure(), LuaValue.isclosure(), LuaValue.TFUNCTION
  - optdouble
```
public double optdouble(double defval)
```
    从类复制的说明: LuaValue
    
    Check that optional argument is a number or string convertible to number and return as double
    
    覆盖:
    
    optdouble 在类中 LuaValue
    
    参数:
    
    defval - double to return if this is nil or none
    
    返回:
    
    this cast to double if numeric, defval if nil or none, throws LuaError otherwise
    
    另请参阅:
    
    LuaValue.optint(int), LuaValue.optinteger(LuaInteger), LuaValue.checkdouble(), LuaValue.todouble(), LuaValue.tonumber(), LuaValue.isnumber(), LuaValue.TNUMBER
  - optfunction
```
public LuaFunction optfunction(LuaFunction defval)
```
    从类复制的说明: LuaValue
    
    Check that optional argument is a function and return as LuaFunction
    A LuaFunction may either be a Java function that implements functionality directly in Java, or a LuaClosure which is a LuaFunction that executes lua bytecode.
    
    覆盖:
    
    optfunction 在类中 LuaValue
    
    参数:
    
    defval - LuaFunction to return if this is nil or none
    
    返回:
    
    this cast to LuaFunction if a function, defval if nil or none, throws LuaError otherwise
    
    另请参阅:
    
    LuaValue.checkfunction(), LuaValue.isfunction(), LuaValue.TFUNCTION
  - optint
```
public int optint(int defval)
```
    从类复制的说明: LuaValue
    
    Check that optional argument is a number or string convertible to number and return as int
    
    覆盖:
    
    optint 在类中 LuaValue
    
    参数:
    
    defval - int to return if this is nil or none
    
    返回:
    
    this cast to int if numeric, defval if nil or none, throws LuaError otherwise
    
    另请参阅:
    
    LuaValue.optdouble(double), LuaValue.optlong(long), LuaValue.optinteger(LuaInteger), LuaValue.checkint(), LuaValue.toint(), LuaValue.tonumber(), LuaValue.isnumber(), LuaValue.TNUMBER
  - optinteger
```
public LuaInteger optinteger(LuaInteger defval)
```
    从类复制的说明: LuaValue
    
    Check that optional argument is a number or string convertible to number and return as LuaInteger
    
    覆盖:
    
    optinteger 在类中 LuaValue
    
    参数:
    
    defval - LuaInteger to return if this is nil or none
    
    返回:
    
    this converted and wrapped in LuaInteger if numeric, defval if nil or none, throws LuaError otherwise
    
    另请参阅:
    
    LuaValue.optdouble(double), LuaValue.optint(int), LuaValue.checkint(), LuaValue.toint(), LuaValue.tonumber(), LuaValue.isnumber(), LuaValue.TNUMBER
  - optlong
```
public long optlong(long defval)
```
    从类复制的说明: LuaValue
    
    Check that optional argument is a number or string convertible to number and return as long
    
    覆盖:
    
    optlong 在类中 LuaValue
    
    参数:
    
    defval - long to return if this is nil or none
    
    返回:
    
    this cast to long if numeric, defval if nil or none, throws LuaError otherwise
    
    另请参阅:
    
    LuaValue.optdouble(double), LuaValue.optint(int), LuaValue.checkint(), LuaValue.toint(), LuaValue.tonumber(), LuaValue.isnumber(), LuaValue.TNUMBER
  - optnumber
```
public LuaNumber optnumber(LuaNumber defval)
```
    从类复制的说明: LuaValue
    
    Check that optional argument is a number or string convertible to number and return as LuaNumber
    
    覆盖:
    
    optnumber 在类中 LuaValue
    
    参数:
    
    defval - LuaNumber to return if this is nil or none
    
    返回:
    
    this cast to LuaNumber if numeric, defval if nil or none, throws LuaError otherwise
    
    另请参阅:
    
    LuaValue.optdouble(double), LuaValue.optlong(long), LuaValue.optint(int), LuaValue.checkint(), LuaValue.toint(), LuaValue.tonumber(), LuaValue.isnumber(), LuaValue.TNUMBER
  - opttable
```
public LuaTable opttable(LuaTable defval)
```
    从类复制的说明: LuaValue
    
    Check that optional argument is a table and return as LuaTable
    
    覆盖:
    
    opttable 在类中 LuaValue
    
    参数:
    
    defval - LuaTable to return if this is nil or none
    
    返回:
    
    this cast to LuaTable if a table, defval if nil or none, throws LuaError if some other type
    
    另请参阅:
    
    LuaValue.checktable(), LuaValue.istable(), LuaValue.TTABLE
  - optthread
```
public LuaThread optthread(LuaThread defval)
```
    从类复制的说明: LuaValue
    
    Check that optional argument is a thread and return as LuaThread
    
    覆盖:
    
    optthread 在类中 LuaValue
    
    参数:
    
    defval - LuaThread to return if this is nil or none
    
    返回:
    
    this cast to LuaTable if a thread, defval if nil or none, throws LuaError if some other type
    
    另请参阅:
    
    LuaValue.checkthread(), LuaValue.isthread(), LuaValue.TTHREAD
  - optjstring
```
public String optjstring(String defval)
```
    从类复制的说明: LuaValue
    
    Check that optional argument is a string or number and return as Java String
    
    覆盖:
    
    optjstring 在类中 LuaValue
    
    参数:
    
    defval - LuaString to return if this is nil or none
    
    返回:
    
    this converted to String if a string or number, defval if nil or none, throws LuaError if some other type
    
    另请参阅:
    
    LuaValue.tojstring(), LuaValue.optstring(LuaString), LuaValue.checkjstring(), LuaValue.toString(), LuaValue.TSTRING
  - optstring
```
public LuaString optstring(LuaString defval)
```
    从类复制的说明: LuaValue
    
    Check that optional argument is a string or number and return as LuaString
    
    覆盖:
    
    optstring 在类中 LuaValue
    
    参数:
    
    defval - LuaString to return if this is nil or none
    
    返回:
    
    this converted to LuaString if a string or number, defval if nil or none, throws LuaError if some other type
    
    另请参阅:
    
    LuaValue.tojstring(), LuaValue.optjstring(String), LuaValue.checkstring(), LuaValue.toString(), LuaValue.TSTRING
  - optuserdata
```
public Object optuserdata(Object defval)
```
    从类复制的说明: LuaValue
    
    Check that optional argument is a userdata and return the Object instance
    
    覆盖:
    
    optuserdata 在类中 LuaValue
    
    参数:
    
    defval - Object to return if this is nil or none
    
    返回:
    
    Object instance of the userdata if a LuaUserdata, defval if nil or none, throws LuaError if some other type
    
    另请参阅:
    
    LuaValue.checkuserdata(), LuaValue.isuserdata(), LuaValue.optuserdata(Class, Object), LuaValue.TUSERDATA
  - optuserdata
```
public Object optuserdata(Class c,
                          Object defval)
```
    从类复制的说明: LuaValue
    
    Check that optional argument is a userdata whose instance is of a type and return the Object instance
    
    覆盖:
    
    optuserdata 在类中 LuaValue
    
    参数:
    
    c - Class to test userdata instance against
    
    defval - Object to return if this is nil or none
    
    返回:
    
    Object instance of the userdata if a LuaUserdata and instance is assignable to c, defval if nil or none, throws LuaError if some other type
    
    另请参阅:
    
    LuaValue.checkuserdata(Class), LuaValue.isuserdata(Class), LuaValue.optuserdata(Object), LuaValue.TUSERDATA
  - optvalue
```
public LuaValue optvalue(LuaValue defval)
```
    从类复制的说明: LuaValue
    
    Perform argument check that this is not nil or none.
    
    覆盖:
    
    optvalue 在类中 LuaValue
    
    参数:
    
    defval - LuaValue to return if this is nil or none
    
    返回:
    
    this if not nil or none, else defval
    
    另请参阅:
    
    LuaValue.NIL, LuaValue.NONE, LuaValue.isnil(), Varargs.isnoneornil(int), LuaValue.TNIL, LuaValue.TNONE

类 LuaNil

字段概要

从类继承的字段 org.luaj.vm2.LuaValue

方法概要

从类继承的方法 org.luaj.vm2.LuaValue

从类继承的方法 org.luaj.vm2.Varargs

从类继承的方法 java.lang.Object

字段详细资料

s_metatable

方法详细资料

type

toString

typename

tojstring

not

toboolean

isnil

getmetatable

equals

checknotnil

isvalidkey

optboolean

optclosure

optdouble

optfunction

optint

optinteger

optlong

optnumber

opttable

optthread

optjstring

optstring

optuserdata

optuserdata

optvalue