java.lang.Object
- org.springframework.context.expression.MapAccessor

所有已实现的接口:
Opcodes, PropertyAccessor, CompilablePropertyAccessor
```
public class MapAccessor
extends Object
implements CompilablePropertyAccessor
```
EL property accessor that knows how to traverse the keys of a standard Map.
从以下版本开始:
3.0
作者:
Juergen Hoeller, Andy Clement

字段概要
- 从接口继承的字段 org.springframework.asm.Opcodes
  AALOAD, AASTORE, ACC_ABSTRACT, ACC_ANNOTATION, ACC_BRIDGE, ACC_DEPRECATED, ACC_ENUM, ACC_FINAL, ACC_INTERFACE, ACC_MANDATED, ACC_MODULE, ACC_NATIVE, ACC_OPEN, ACC_PRIVATE, ACC_PROTECTED, ACC_PUBLIC, ACC_STATIC, ACC_STATIC_PHASE, ACC_STRICT, ACC_SUPER, ACC_SYNCHRONIZED, ACC_SYNTHETIC, ACC_TRANSIENT, ACC_TRANSITIVE, ACC_VARARGS, ACC_VOLATILE, ACONST_NULL, ALOAD, ANEWARRAY, ARETURN, ARRAYLENGTH, ASM4, ASM5, ASM6, ASTORE, ATHROW, BALOAD, BASTORE, BIPUSH, CALOAD, CASTORE, CHECKCAST, D2F, D2I, D2L, DADD, DALOAD, DASTORE, DCMPG, DCMPL, DCONST_0, DCONST_1, DDIV, DLOAD, DMUL, DNEG, DOUBLE, DREM, DRETURN, DSTORE, DSUB, DUP, DUP_X1, DUP_X2, DUP2, DUP2_X1, DUP2_X2, F_APPEND, F_CHOP, F_FULL, F_NEW, F_SAME, F_SAME1, F2D, F2I, F2L, FADD, FALOAD, FASTORE, FCMPG, FCMPL, FCONST_0, FCONST_1, FCONST_2, FDIV, FLOAD, FLOAT, FMUL, FNEG, FREM, FRETURN, FSTORE, FSUB, GETFIELD, GETSTATIC, GOTO, H_GETFIELD, H_GETSTATIC, H_INVOKEINTERFACE, H_INVOKESPECIAL, H_INVOKESTATIC, H_INVOKEVIRTUAL, H_NEWINVOKESPECIAL, H_PUTFIELD, H_PUTSTATIC, I2B, I2C, I2D, I2F, I2L, I2S, IADD, IALOAD, IAND, IASTORE, ICONST_0, ICONST_1, ICONST_2, ICONST_3, ICONST_4, ICONST_5, ICONST_M1, IDIV, IF_ACMPEQ, IF_ACMPNE, IF_ICMPEQ, IF_ICMPGE, IF_ICMPGT, IF_ICMPLE, IF_ICMPLT, IF_ICMPNE, IFEQ, IFGE, IFGT, IFLE, IFLT, IFNE, IFNONNULL, IFNULL, IINC, ILOAD, IMUL, INEG, INSTANCEOF, INTEGER, INVOKEDYNAMIC, INVOKEINTERFACE, INVOKESPECIAL, INVOKESTATIC, INVOKEVIRTUAL, IOR, IREM, IRETURN, ISHL, ISHR, ISTORE, ISUB, IUSHR, IXOR, JSR, L2D, L2F, L2I, LADD, LALOAD, LAND, LASTORE, LCMP, LCONST_0, LCONST_1, LDC, LDIV, LLOAD, LMUL, LNEG, LONG, LOOKUPSWITCH, LOR, LREM, LRETURN, LSHL, LSHR, LSTORE, LSUB, LUSHR, LXOR, MONITORENTER, MONITOREXIT, MULTIANEWARRAY, NEW, NEWARRAY, NOP, NULL, POP, POP2, PUTFIELD, PUTSTATIC, RET, RETURN, SALOAD, SASTORE, SIPUSH, SWAP, T_BOOLEAN, T_BYTE, T_CHAR, T_DOUBLE, T_FLOAT, T_INT, T_LONG, T_SHORT, TABLESWITCH, TOP, UNINITIALIZED_THIS, V1_1, V1_2, V1_3, V1_4, V1_5, V1_6, V1_7, V1_8, V1_9

构造器概要
构造器
构造器说明
MapAccessor()

方法概要

所有方法实例方法具体方法
修饰符和类型	方法	说明
`boolean`	`canRead(EvaluationContext context, Object target, String name)`	Called to determine if a resolver instance is able to access a specified property on a specified target object.
`boolean`	`canWrite(EvaluationContext context, Object target, String name)`	Called to determine if a resolver instance is able to write to a specified property on a specified target object.
`void`	`generateCode(String propertyName, MethodVisitor mv, CodeFlow cf)`	Generate the bytecode the performs the access operation into the specified MethodVisitor using context information from the codeflow where necessary.
`Class<?>`	`getPropertyType()`	Return the type of the accessed property - may only be known once an access has occurred.
`Class<?>[]`	`getSpecificTargetClasses()`	Return an array of classes for which this resolver should be called.
`boolean`	`isCompilable()`	Return `true` if this property accessor is currently suitable for compilation.
`TypedValue`	`read(EvaluationContext context, Object target, String name)`	Called to read a property from a specified target object.
`void`	`write(EvaluationContext context, Object target, String name, Object newValue)`	Called to write to a property on a specified target object.

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

- 构造器详细资料
  - MapAccessor
```
public MapAccessor()
```
- 方法详细资料
  - getSpecificTargetClasses
```
public Class<?>[] getSpecificTargetClasses()
```
    从接口复制的说明: PropertyAccessor
    Return an array of classes for which this resolver should be called.
    >Returning null indicates this is a general resolver that can be called in an attempt to resolve a property on any type.
    指定者:
    getSpecificTargetClasses 在接口中 PropertyAccessor
    返回:
    an array of classes that this resolver is suitable for (or null if a general resolver)
  - canRead
```
public boolean canRead(EvaluationContext context,
                       Object target,
                       String name)
                throws AccessException
```
    从接口复制的说明: PropertyAccessor
    Called to determine if a resolver instance is able to access a specified property on a specified target object.
    指定者:
    canRead 在接口中 PropertyAccessor
    参数:
    context - the evaluation context in which the access is being attempted
    target - the target object upon which the property is being accessed
    name - the name of the property being accessed
    返回:
    true if this resolver is able to read the property
    抛出:
    AccessException - if there is any problem determining whether the property can be read
  - read
```
public TypedValue read(EvaluationContext context,
                       Object target,
                       String name)
                throws AccessException
```
    从接口复制的说明: PropertyAccessor
    Called to read a property from a specified target object. Should only succeed if PropertyAccessor.canRead(org.springframework.expression.EvaluationContext, java.lang.Object, java.lang.String) also returns true.
    指定者:
    read 在接口中 PropertyAccessor
    参数:
    context - the evaluation context in which the access is being attempted
    target - the target object upon which the property is being accessed
    name - the name of the property being accessed
    返回:
    a TypedValue object wrapping the property value read and a type descriptor for it
    抛出:
    AccessException - if there is any problem accessing the property value
  - canWrite
```
public boolean canWrite(EvaluationContext context,
                        Object target,
                        String name)
                 throws AccessException
```
    从接口复制的说明: PropertyAccessor
    Called to determine if a resolver instance is able to write to a specified property on a specified target object.
    指定者:
    canWrite 在接口中 PropertyAccessor
    参数:
    context - the evaluation context in which the access is being attempted
    target - the target object upon which the property is being accessed
    name - the name of the property being accessed
    返回:
    true if this resolver is able to write to the property
    抛出:
    AccessException - if there is any problem determining whether the property can be written to
  - write
```
public void write(EvaluationContext context,
                  Object target,
                  String name,
                  Object newValue)
           throws AccessException
```
    从接口复制的说明: PropertyAccessor
    Called to write to a property on a specified target object. Should only succeed if PropertyAccessor.canWrite(org.springframework.expression.EvaluationContext, java.lang.Object, java.lang.String) also returns true.
    指定者:
    write 在接口中 PropertyAccessor
    参数:
    context - the evaluation context in which the access is being attempted
    target - the target object upon which the property is being accessed
    name - the name of the property being accessed
    newValue - the new value for the property
    抛出:
    AccessException - if there is any problem writing to the property value
  - isCompilable
```
public boolean isCompilable()
```
    从接口复制的说明: CompilablePropertyAccessor
    Return true if this property accessor is currently suitable for compilation.
    指定者:
    isCompilable 在接口中 CompilablePropertyAccessor
  - getPropertyType
```
public Class<?> getPropertyType()
```
    从接口复制的说明: CompilablePropertyAccessor
    Return the type of the accessed property - may only be known once an access has occurred.
    指定者:
    getPropertyType 在接口中 CompilablePropertyAccessor
  - generateCode
```
public void generateCode(String propertyName,
                         MethodVisitor mv,
                         CodeFlow cf)
```
    从接口复制的说明: CompilablePropertyAccessor
    Generate the bytecode the performs the access operation into the specified MethodVisitor using context information from the codeflow where necessary.
    指定者:
    generateCode 在接口中 CompilablePropertyAccessor
    参数:
    propertyName - the name of the property
    mv - the Asm method visitor into which code should be generated
    cf - the current state of the expression compiler

类 MapAccessor

字段概要

从接口继承的字段 org.springframework.asm.Opcodes

构造器概要

方法概要

从类继承的方法 java.lang.Object

构造器详细资料

MapAccessor

方法详细资料

getSpecificTargetClasses

canRead

read

canWrite

write

isCompilable

getPropertyType

generateCode