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/*
* Copyright (c) 2000, 2021, Oracle and/or its affiliates.
*
* Licensed under the Universal Permissive License v 1.0 as shown at
* http://oss.oracle.com/licenses/upl.
*/
package com.tangosol.util.extractor;
import com.oracle.coherence.common.internal.util.CanonicalNames;
import com.tangosol.internal.util.extractor.TargetReflectionDescriptor;
import com.tangosol.internal.util.invoke.Lambdas;
import com.tangosol.io.ExternalizableLite;
import com.tangosol.io.pof.PofReader;
import com.tangosol.io.pof.PofWriter;
import com.tangosol.io.pof.PortableObject;
import com.tangosol.util.ClassHelper;
import com.tangosol.util.ValueExtractor;
import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
import java.io.NotActiveException;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.Map;
import javax.json.bind.annotation.JsonbCreator;
import javax.json.bind.annotation.JsonbProperty;
/**
* Universal ValueExtractor implementation.
*
* Either a property or method based extractor based on parameters passed to
* constructor {@link #UniversalExtractor(String, Object[], int)}.
* Generally, the name value passed to the {@link UniversalExtractor} constructor
* represents a property unless sName value ends in {@link #METHOD_SUFFIX},
* "()",
* then this instance is a reflection based method extractor.
* Special cases are described in the constructor documentation.
*
* {@link AbstractExtractor#equals(Object)} and {@link AbstractExtractor#hashCode()}
* describe how this Extractor can be equivalent to other {@link ValueExtractor}
* implementations.
*
* @param the type of the value to extract from
* @param the type of value that will be extracted
*
* @author cp/gg 2002.11.01, ew 2007.02.01, jf 2017.11.20
*
* @since 12.2.1.4
*
* @see ChainedExtractor
*/
public class UniversalExtractor
extends AbstractExtractor
implements ValueExtractor, ExternalizableLite, PortableObject
{
// ----- constructors ---------------------------------------------------
/**
* Default constructor (necessary for the ExternalizableLite interface).
*/
public UniversalExtractor()
{
}
/**
* Construct a UniversalExtractor based on syntax of sName.
*
* If sName does not end in {@link #METHOD_SUFFIX},
* "()", this extractor is a property extractor. If sName is prefixed with
* one of the {@link #BEAN_ACCESSOR_PREFIXES} and ends in the {@link #METHOD_SUFFIX},
* this extractor is a property extractor. Otherwise,
* if the sName just ends in {#link #METHOD_SUFFIX},
* this extractor is considered a method extractor.
*
* @param sName a method or property name
*/
public UniversalExtractor(String sName)
{
this(sName, null, VALUE);
}
/**
* Construct a UniversalExtractor based on a name and optional
* parameters.
*
* If sName does not end in {@link #METHOD_SUFFIX}, "()",
* and has no aoParams,this extractor is a property extractor.
* If sName is prefixed with
* one of the {@link #BEAN_ACCESSOR_PREFIXES}, ends in {@link #METHOD_SUFFIX}
* and has no aoParams,this extractor is a property extractor.
* Otherwise, if the sNamejust ends in {#link #METHOD_SUFFIX},
* this extractor is considered a method extractor.
*
* @param sName a method or property name
* @param aoParam the array of arguments to be used in the method
* invocation; may be null
*
* @throws IllegalArgumentException when sName does not end in
* {@link #METHOD_SUFFIX} and aoParam array length is one or more.
*/
public UniversalExtractor(String sName, Object[] aoParam)
{
this(sName, aoParam, VALUE);
}
/**
* Construct a UniversalExtractor based on a name, optional
* parameters and the entry extraction target.
*
* If sName does not end in {@link #METHOD_SUFFIX}, "()",
* this extractor is a property extractor. If sName is prefixed with
* one of the {@link #BEAN_ACCESSOR_PREFIXES} and ends in {@link #METHOD_SUFFIX},
* this extractor is a property extractor. If the sName
* just ends in {@link #METHOD_SUFFIX}, this extractor is considered a method
* extractor.
*
* @param sName a method or property name
* @param aoParam the array of arguments to be used in the method
* invocation; may be null
* @param nTarget one of the {@link #VALUE} or {@link #KEY} values
*
* @throws IllegalArgumentException when sName does not end in
* {@link #METHOD_SUFFIX} and aoParam array length is one or more.
*/
@JsonbCreator
public UniversalExtractor(@JsonbProperty("name")
String sName,
@JsonbProperty("params")
Object[] aoParam,
@JsonbProperty("target")
int nTarget)
{
azzert(sName != null);
if (aoParam != null && aoParam.length > 0 && !sName.endsWith(METHOD_SUFFIX))
{
throw new IllegalArgumentException("UniversalExtractor constructor: parameter sName[value:" + sName + "] must end with method suffix \"" + METHOD_SUFFIX + "\" when optional parameters provided");
}
m_sName = sName;
m_aoParam = aoParam;
m_nTarget = nTarget;
init();
}
// ----- ValueExtractor interface ---------------------------------------
/**
* Extract from target using reflection or map access.
*
* If name is a property, reflection accessor method lookup on {@code T} fails and
* {@code oTarget} is an instance {@link Map}, use canonical name to get value from
* target.
*
* @param oTarget the target
*
* @return value extracted from target
*/
public E extract(T oTarget)
{
if (oTarget == null)
{
return null;
}
TargetReflectionDescriptor targetPrev = m_cacheTarget;
try
{
if (targetPrev != null && oTarget.getClass() == targetPrev.getTargetClass())
{
return (E) (targetPrev.isMap()
? (((Map) oTarget).get(getCanonicalName()))
: targetPrev.getMethod().invoke(oTarget, m_aoParam));
}
return extractComplex(oTarget);
}
catch (NullPointerException e)
{
throw new RuntimeException(suggestExtractFailureCause(oTarget.getClass(), false));
}
catch (Exception e)
{
throw ensureRuntimeException(e,
oTarget.getClass().getName() + this + '(' + oTarget +')');
}
}
@Override
public String getCanonicalName()
{
String sCName = Lambdas.getValueExtractorCanonicalName(this);
if (sCName == null)
{
sCName = m_sNameCanon = CanonicalNames.computeValueExtractorCanonicalName(m_sName, m_aoParam);
}
return sCName;
}
// ----- Object methods -------------------------------------------------
/**
* Compare the {@code UniversalExtractor} with another object to determine equality.
*
* {@link AbstractExtractor#equals(Object)} contract takes precedence when applicable,
* falling back to implementation specific equals.
*
* Two UniversalExtractor objects, re1 and re2 are considered
* equal if re1.extract(o) equals re2.extract(o) for
* all values of o.
*
* @return {@code true} iff this {@code UniversalExtractor} and the passed object are
* equivalent
*/
@Override
public boolean equals(Object o)
{
// the super.equals() uses the canonical name comparison (if applies);
// if that succeeds, no other checks are to be made.
if (super.equals(o))
{
return true;
}
else if (isCanonicallyEquatable(o))
{
return false;
}
if (o instanceof UniversalExtractor)
{
UniversalExtractor that = (UniversalExtractor) o;
return this.m_nTarget == that.m_nTarget &&
equals(this.m_sName, that.m_sName) &&
equalsDeep(this.m_aoParam, that.m_aoParam);
}
return false;
}
/**
* HashCode value is hashCode of non-null {@link ValueExtractor#getCanonicalName() canonical name};
* otherwise, it is the hashCode of {@code sName} passed to {#link UniversalExtractor(String)}.
*
* @return an integer hash value for this UniversalExtractor object
*/
@Override
public int hashCode()
{
String sCName = getCanonicalName();
return sCName == null ? m_sName.hashCode(): super.hashCode();
}
/**
* Provide a human-readable description of this {@code UniversalExtractor} object.
*
* @return a human-readable description of this {@code UniversalExtractor} object
*/
@Override
public String toString()
{
Object[] aoParam = m_aoParam;
int cParams = aoParam == null ? 0 : aoParam.length;
StringBuilder sb = new StringBuilder();
if (m_nTarget == KEY)
{
sb.append(".getKey()");
}
if (isPropertyExtractor())
{
String sCName = getCanonicalName();
if (sCName != null && sCName.length() > 0)
{
sb.append("." + sCName);
return sb.toString();
}
else
{
return "";
}
}
else if (isMethodExtractor())
{
sb.append('.').append(getMethodName()).append('(');
for (int i = 0; i < cParams; i++)
{
if (i != 0)
{
sb.append(", ");
}
sb.append(aoParam[i]);
}
sb.append(')');
}
return sb.toString();
}
// ----- accessors and helpers ------------------------------------------
/**
* Called in constructor and deserializers.
*/
protected void init()
{
String sCName = getCanonicalName();
m_fMethod = sCName == null || sCName.endsWith(METHOD_SUFFIX);
}
/**
* Return the method name that this extractor is configured to invoke.
* If a reflection-based method extractor, {@link #isMethodExtractor()}, return
* the method name to be invoked. If a property extractor, return the likely JavaBean accessor
* method name.
*
* @return method name
*/
public String getMethodName()
{
final int METHOD_SUFFIX_LENGTH = METHOD_SUFFIX.length();
String sCName = getCanonicalName();
String sName = sCName == null ? m_sName : sCName;
return isMethodExtractor() ?
sName.substring(0, sName.length() - METHOD_SUFFIX_LENGTH) :
"get" + Character.toUpperCase(sCName.charAt(0)) + sCName.substring(1);
}
/**
* Return the name passed into {@link #UniversalExtractor(String)}.
*
* @return the name of extraction attribute.
*/
public String getName()
{
return m_sName;
}
/**
* Return the property name of this extractor.
*
* @return property name of this extractor; otherwise, return null.
*/
public String getPropertyName()
{
return isPropertyExtractor() ? getCanonicalName() : null;
}
/**
* Return true if this is a Property extractor.
*
* @return true if this a property extractor.
*/
public boolean isPropertyExtractor()
{
return !m_fMethod;
}
/**
* Return true if this a method extractor.
*
* @return true if this is a method extractor.
*/
public boolean isMethodExtractor()
{
return m_fMethod;
}
/**
* Return the array of arguments used to invoke the method.
*
* @return the array of arguments used to invoke the method
*/
public Object[] getParameters()
{
return m_aoParam;
}
/**
* Extract from target using reflection or map access.
* If name is a property, reflection accessor method lookup on {@code T} fails and
* {@code T} is an instance {@link Map}, use canonical name to get value from
* target. If successful, cache the reflection computation.
*
* @param oTarget the target
*
* @return value extracted from target
*
* @throws InvocationTargetException if reflection method lookup fails
* @throws IllegalAccessException if reflection method lookup fails
*/
protected E extractComplex(T oTarget)
throws InvocationTargetException, IllegalAccessException
{
Class clzTarget = oTarget.getClass();
Object[] aoParam = m_aoParam;
Class[] clzParam = ClassHelper.getClassArray(aoParam);
String sCName = getCanonicalName();
boolean fProperty = isPropertyExtractor();
Method method = null;
// check for javabean accessors
if (fProperty)
{
String sBeanAttribute = Character.toUpperCase(sCName.charAt(0)) + sCName.substring(1);
for (int cchPrefix = 0; cchPrefix < BEAN_ACCESSOR_PREFIXES.length && method == null; cchPrefix++)
{
method = ClassHelper.findMethod(clzTarget,
BEAN_ACCESSOR_PREFIXES[cchPrefix] + sBeanAttribute, clzParam, false);
}
}
else
{
// lookup method via reflection
method = ClassHelper.findMethod(clzTarget, getMethodName(), clzParam, false);
}
if (method == null)
{
if (fProperty && oTarget instanceof Map)
{
m_cacheTarget = new TargetReflectionDescriptor(clzTarget);
return (E) ((Map) oTarget).get(sCName);
}
}
else
{
// only check if reflection is allowed when method is non null and not cached from previous extract
if (!ClassHelper.isReflectionAllowed(oTarget))
{
m_cacheTarget = null;
throw new IllegalArgumentException(suggestExtractFailureCause(clzTarget, true));
}
m_cacheTarget = new TargetReflectionDescriptor(clzTarget, method);
}
return (E) method.invoke(oTarget, aoParam);
}
/**
* Return a message suggesting a possible cause for a failure to extract a
* value.
*
* @param clzTarget the target object's class
* @param fFiltered pass {@code true} if the type was an invalid reflection target type
*
* @return the suggested reason for the failure of the extraction
*/
private String suggestExtractFailureCause(Class clzTarget, boolean fFiltered)
{
TargetReflectionDescriptor targetPrev = m_cacheTarget;
if (targetPrev != null && targetPrev.isMap())
{
return "Failed accessing target of class " + clzTarget.getCanonicalName() + " using property " + getCanonicalName();
}
String sMsg = "Missing or inaccessible method: " +
clzTarget.getName() + this;
if (com.tangosol.util.MapEvent.class.isAssignableFrom(clzTarget))
{
sMsg += " (the object is a com.oracle.coherence.util.MapEvent, which may "
+ "suggest that a raw com.oracle.coherence.util.Filter is "
+ "being used to filter map events rather than a "
+ "com.oracle.coherence.util.filter.MapEventFilter)";
}
if (fFiltered)
{
sMsg += " (The type, " + clzTarget.getName() + ", is disallowed as a reflection target by the current "
+ "reflection filter configuration)";
}
return sMsg;
}
/**
* Return a ValueExtractor representing dot separated list of property
* and/or method names.
*
* @param sNames dot-delimited property and/or methods name(s)
*
* @param the type of the value to extract from
* @param the type of value that will be extracted
*
* @return {@link UniversalExtractor} if only one name in parameter; otherwise, return
* a {@link ChainedExtractor} with a UniversalExtractor for each name.
*/
static public ValueExtractor createExtractor(String sNames)
{
if (sNames == null || sNames.length() == 0)
{
return IdentityExtractor.INSTANCE;
}
else
{
return sNames.indexOf('.') < 0 ?
new UniversalExtractor<>(sNames) :
new ChainedExtractor<>(ChainedExtractor.createExtractors(sNames));
}
}
// ----- ExternalizableLite interface -----------------------------------
/**
* {@inheritDoc}
*/
public void readExternal(DataInput in)
throws IOException
{
m_sName = readUTF(in);
int cParams = readInt(in);
azzert(cParams < 256, "Unexpected number of method parameters.");
Object[] aoParam = cParams == 0 ? null : new Object[cParams];
for (int i = 0; i < cParams; i++)
{
aoParam[i] = readObject(in);
}
m_aoParam = aoParam;
m_nTarget = readInt(in);
init();
}
/**
* {@inheritDoc}
*/
public void writeExternal(DataOutput out)
throws IOException
{
String sMethod = m_sName;
if (sMethod == null)
{
throw new NotActiveException(
"UniversalExtractor was constructed without a method name");
}
Object[] aoParam = m_aoParam;
int cParams = aoParam == null ? 0 : aoParam.length;
writeUTF(out, sMethod);
writeInt(out, cParams);
for (int i = 0; i < cParams; i++)
{
writeObject(out, aoParam[i]);
}
writeInt(out, m_nTarget);
}
// ----- PortableObject interface ---------------------------------------
/**
* {@inheritDoc}
*/
public void readExternal(PofReader in)
throws IOException
{
m_sName = in.readString(0);
m_aoParam = in.readArray(1, Object[]::new);
m_nTarget = in.readInt(2);
init();
}
/**
* {@inheritDoc}
*/
public void writeExternal(PofWriter out)
throws IOException
{
String sMethod = m_sName;
if (sMethod == null)
{
throw new NotActiveException(
"UniversalExtractor was constructed without a method name");
}
out.writeString(0, sMethod);
out.writeObjectArray(1, m_aoParam);
out.writeInt(2, m_nTarget);
}
// ----- constants ------------------------------------------------------
/**
* JavaBean accessor prefixes.
*/
public final static String[] BEAN_ACCESSOR_PREFIXES = CanonicalNames.VALUE_EXTRACTOR_BEAN_ACCESSOR_PREFIXES;
/**
* If {@link #m_sName} ends with this suffix, it represents a method name.
*/
public final static String METHOD_SUFFIX = CanonicalNames.VALUE_EXTRACTOR_METHOD_SUFFIX;
// ----- data members --------------------------------------------------
/**
* A method or property name.
*/
@JsonbProperty("name")
protected String m_sName;
/**
* The parameter array. Must be null or zero length for a property based extractor.
*/
@JsonbProperty("params")
protected Object[] m_aoParam;
/**
* Canonical name for this extractor.
*
* Note: subclasses are responsible for initialization and POF and/or
* Lite serialization of this field.
*/
protected transient String m_sNameCanon = null;
/**
* Cached reflection computations for previous target parameter.
* This cache enables very fast reference based matching in a homogeneous cache.
*
* @see #extractComplex(T)
*/
private transient TargetReflectionDescriptor m_cacheTarget;
/**
* True if a method extractor; false if a property extractor.
*/
private transient boolean m_fMethod;
}