类 Elvis
- java.lang.Object
- org.springframework.expression.spel.ast.SpelNodeImpl
- org.springframework.expression.spel.ast.Elvis
public class Elvis extends SpelNodeImpl
Represents the elvis operator ?:. For an expression "a?:b" if a is not null, the value of the expression is "a", if a is null then the value of the expression is "b".- 从以下版本开始:
- 3.0
- 作者:
- Andy Clement, Juergen Hoeller
字段概要
从类继承的字段 org.springframework.expression.spel.ast.SpelNodeImpl
children, exitTypeDescriptor
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, ASM7, ASM8_EXPERIMENTAL, 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, SOURCE_DEPRECATED, SOURCE_MASK, SWAP, T_BOOLEAN, T_BYTE, T_CHAR, T_DOUBLE, T_FLOAT, T_INT, T_LONG, T_SHORT, TABLESWITCH, TOP, UNINITIALIZED_THIS, V_PREVIEW, V1_1, V1_2, V1_3, V1_4, V1_5, V1_6, V1_7, V1_8, V10, V11, V12, V13, V14, V15, V9
构造器概要
构造器 构造器 说明 Elvis(int startPos, int endPos, SpelNodeImpl... args)
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 void
generateCode(MethodVisitor mv, CodeFlow cf)
Generate the bytecode for this node into the supplied visitor.TypedValue
getValueInternal(ExpressionState state)
Evaluate the condition and if not null, return it.boolean
isCompilable()
Check whether a node can be compiled to bytecode.String
toStringAST()
Return the string form the this AST node.从类继承的方法 org.springframework.expression.spel.ast.SpelNodeImpl
generateCodeForArgument, generateCodeForArguments, getChild, getChildCount, getEndPosition, getExitDescriptor, getObjectClass, getStartPosition, getTypedValue, getValue, getValue, getValueRef, isWritable, nextChildIs, setValue
构造器详细资料
Elvis
public Elvis(int startPos, int endPos, SpelNodeImpl... args)
方法详细资料
getValueInternal
public TypedValue getValueInternal(ExpressionState state) throws EvaluationException
Evaluate the condition and if not null, return it. If it is null, return the other value.- 指定者:
getValueInternal
在类中SpelNodeImpl
- 参数:
state
- the expression state- 抛出:
EvaluationException
- if the condition does not evaluate correctly to a boolean or there is a problem executing the chosen alternative
toStringAST
public String toStringAST()
从接口复制的说明:SpelNode
Return the string form the this AST node.- 返回:
- the string form
isCompilable
public boolean isCompilable()
从类复制的说明:SpelNodeImpl
Check whether a node can be compiled to bytecode. The reasoning in each node may be different but will typically involve checking whether the exit type descriptor of the node is known and any relevant child nodes are compilable.- 覆盖:
isCompilable
在类中SpelNodeImpl
- 返回:
true
if this node can be compiled to bytecode
generateCode
public void generateCode(MethodVisitor mv, CodeFlow cf)
从类复制的说明:SpelNodeImpl
Generate the bytecode for this node into the supplied visitor. Context info about the current expression being compiled is available in the codeflow object, e.g. including information about the type of the object currently on the stack.- 覆盖:
generateCode
在类中SpelNodeImpl
- 参数:
mv
- the ASM MethodVisitor into which code should be generatedcf
- a context object with info about what is on the stack