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摘要: 嵌套 | 字段 | 构造方法 | 方法 | 详细信息: 字段 | 构造方法 | 方法 |
java.lang.Objectorg.activiti.engine.impl.javax.el.ELResolver
org.activiti.engine.impl.javax.el.ListELResolver
public class ListELResolver
Defines property resolution behavior on instances of java.util.List. This resolver handles base
objects of type java.util.List. It accepts any object as a property and coerces that object into
an integer index into the list. The resulting value is the value in the list at that index. This
resolver can be constructed in read-only mode, which means that isReadOnly will always return
true and setValue(ELContext, Object, Object, Object)
will always throw
PropertyNotWritableException. ELResolvers are combined together using CompositeELResolver
s, to define rich semantics for evaluating an expression. See the javadocs for ELResolver
for details.
字段摘要 |
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从类 org.activiti.engine.impl.javax.el.ELResolver 继承的字段 |
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RESOLVABLE_AT_DESIGN_TIME, TYPE |
构造方法摘要 | |
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ListELResolver()
Creates a new read/write ListELResolver. |
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ListELResolver(boolean readOnly)
Creates a new ListELResolver whose read-only status is determined by the given parameter. |
方法摘要 | |
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Class<?> |
getCommonPropertyType(ELContext context,
Object base)
If the base object is a list, returns the most general type that this resolver accepts for the property argument. |
Iterator<FeatureDescriptor> |
getFeatureDescriptors(ELContext context,
Object base)
Always returns null, since there is no reason to iterate through set set of all integers. |
Class<?> |
getType(ELContext context,
Object base,
Object property)
If the base object is a list, returns the most general acceptable type for a value in this list. |
Object |
getValue(ELContext context,
Object base,
Object property)
If the base object is a list, returns the value at the given index. |
boolean |
isReadOnly(ELContext context,
Object base,
Object property)
If the base object is a list, returns whether a call to setValue(ELContext, Object, Object, Object) will always fail. |
void |
setValue(ELContext context,
Object base,
Object property,
Object value)
If the base object is a list, attempts to set the value at the given index with the given value. |
从类 org.activiti.engine.impl.javax.el.ELResolver 继承的方法 |
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invoke |
从类 java.lang.Object 继承的方法 |
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clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
构造方法详细信息 |
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public ListELResolver()
public ListELResolver(boolean readOnly)
readOnly
- true if this resolver cannot modify lists; false otherwise.方法详细信息 |
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public Class<?> getCommonPropertyType(ELContext context, Object base)
ELResolver
中的 getCommonPropertyType
context
- The context of this evaluation.base
- The list to analyze. Only bases of type List are handled by this resolver.
public Iterator<FeatureDescriptor> getFeatureDescriptors(ELContext context, Object base)
ELResolver
中的 getFeatureDescriptors
context
- The context of this evaluation.base
- The list to analyze. Only bases of type List are handled by this resolver.
public Class<?> getType(ELContext context, Object base, Object property)
ELResolver
中的 getType
context
- The context of this evaluation.base
- The list to analyze. Only bases of type List are handled by this resolver.property
- The index of the element in the list to return the acceptable type for. Will be
coerced into an integer, but otherwise ignored by this resolver.
PropertyNotFoundException
- if the given index is out of bounds for this list.
IllegalArgumentException
- if the property could not be coerced into an integer.
NullPointerException
- if context is null
ELException
- if an exception was thrown while performing the property or variable resolution.
The thrown exception must be included as the cause property of this exception, if
available.public Object getValue(ELContext context, Object base, Object property)
ELResolver
中的 getValue
context
- The context of this evaluation.base
- The list to analyze. Only bases of type List are handled by this resolver.property
- The index of the element in the list to return the acceptable type for. Will be
coerced into an integer, but otherwise ignored by this resolver.
PropertyNotFoundException
- if the given index is out of bounds for this list.
IllegalArgumentException
- if the property could not be coerced into an integer.
NullPointerException
- if context is null
ELException
- if an exception was thrown while performing the property or variable resolution.
The thrown exception must be included as the cause property of this exception, if
available.public boolean isReadOnly(ELContext context, Object base, Object property)
setValue(ELContext, Object, Object, Object)
will always fail. If the base is a List,
the propertyResolved property of the ELContext object must be set to true by this resolver,
before returning. If this property is not true after this method is called, the caller should
ignore the return value. If this resolver was constructed in read-only mode, this method will
always return true. If a List was created using java.util.Collections.unmodifiableList(List),
this method must return true. Unfortunately, there is no Collections API method to detect
this. However, an implementation can create a prototype unmodifiable List and query its
runtime type to see if it matches the runtime type of the base object as a workaround.
ELResolver
中的 isReadOnly
context
- The context of this evaluation.base
- The list to analyze. Only bases of type List are handled by this resolver.property
- The index of the element in the list to return the acceptable type for. Will be
coerced into an integer, but otherwise ignored by this resolver.
PropertyNotFoundException
- if the given index is out of bounds for this list.
IllegalArgumentException
- if the property could not be coerced into an integer.
NullPointerException
- if context is null
ELException
- if an exception was thrown while performing the property or variable resolution.
The thrown exception must be included as the cause property of this exception, if
available.public void setValue(ELContext context, Object base, Object property, Object value)
ELResolver
中的 setValue
context
- The context of this evaluation.base
- The list to analyze. Only bases of type List are handled by this resolver.property
- The index of the element in the list to return the acceptable type for. Will be
coerced into an integer, but otherwise ignored by this resolver.value
- The value to be set at the given index.
ClassCastException
- if the class of the specified element prevents it from being added to this list.
PropertyNotFoundException
- if the given index is out of bounds for this list.
PropertyNotWritableException
- if this resolver was constructed in read-only mode, or if the set operation is
not supported by the underlying list.
IllegalArgumentException
- if the property could not be coerced into an integer.
NullPointerException
- if context is null
ELException
- if an exception was thrown while performing the property or variable resolution.
The thrown exception must be included as the cause property of this exception, if
available.
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上一个类 下一个类 | 框架 无框架 | |||||||||
摘要: 嵌套 | 字段 | 构造方法 | 方法 | 详细信息: 字段 | 构造方法 | 方法 |