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univocity's open source parsers for processing different text formats using a consistent API
/*******************************************************************************
* Copyright 2014 uniVocity Software Pty Ltd
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
******************************************************************************/
package com.univocity.parsers.annotations.helpers;
import com.univocity.parsers.annotations.*;
import com.univocity.parsers.common.*;
import com.univocity.parsers.common.beans.*;
import java.lang.reflect.*;
import static com.univocity.parsers.annotations.helpers.AnnotationHelper.*;
/**
* A helper class with information about the location of an field annotated with {@link Parsed} in a record.
*
* @author uniVocity Software Pty Ltd - [email protected]
*/
public class FieldMapping {
private final Class parentClass;
private final AnnotatedElement target;
private int index;
private String fieldName;
private final Class beanClass;
private final Method readMethod;
private final Method writeMethod;
private boolean accessible;
private final boolean primitive;
private final Object defaultPrimitiveValue;
private Boolean applyDefault = null;
private Class fieldType;
private boolean primitiveNumber;
/**
* Creates the mapping and identifies how it is mapped (by name or by index)
*
* @param beanClass the class that contains a the given field.
* @param target a {@link java.lang.reflect.Field} or {@link java.lang.reflect.Method} annotated with {@link Parsed}
* @param property the property descriptor of this field, if any. If this bean does not have getters/setters, it will be accessed directly.
* @param transformer an optional {@link HeaderTransformer} to modify header names/positions in attributes of {@link Nested} classes.
* @param headers list of headers parsed from the input or manually set with {@link CommonSettings#setHeaders(String...)}
*/
public FieldMapping(Class beanClass, AnnotatedElement target, PropertyWrapper property, HeaderTransformer transformer, String[] headers) {
this.beanClass = beanClass;
this.target = target;
if (target instanceof Field) {
this.readMethod = property != null ? property.getReadMethod() : null;
this.writeMethod = property != null ? property.getWriteMethod() : null;
} else {
Method method = (Method) target;
this.readMethod = method.getReturnType() != Void.class ? method : null;
this.writeMethod = method.getParameterTypes().length != 0 ? method : null;
}
Class typeToSet;
if (target != null) {
typeToSet = getType(target);
parentClass = getDeclaringClass(target);
} else if (writeMethod != null && writeMethod.getParameterTypes().length == 1) {
typeToSet = writeMethod.getParameterTypes()[0];
parentClass = writeMethod.getDeclaringClass();
} else {
typeToSet = Object.class;
if (readMethod != null) {
parentClass = readMethod.getDeclaringClass();
} else {
parentClass = beanClass;
}
}
primitive = typeToSet.isPrimitive();
defaultPrimitiveValue = getDefaultPrimitiveValue(typeToSet);
primitiveNumber = (defaultPrimitiveValue instanceof Number);
determineFieldMapping(transformer, headers);
fieldType = typeToSet;
}
private void determineFieldMapping(HeaderTransformer transformer, String[] headers) {
Parsed parsed = findAnnotation(target, Parsed.class);
String name = "";
if (parsed != null) { //field can be annotated with @Nested only. In this case we get the original field name
index = AnnotationRegistry.getValue(target, parsed, "index", parsed.index());
if (index >= 0) {
fieldName = null;
if (transformer != null) {
index = transformer.transformIndex(target, index);
}
return;
}
String[] fields = AnnotationRegistry.getValue(target, parsed, "field", parsed.field());
if (fields.length > 1 && headers != null) {
for (int i = 0; i < headers.length; i++) {
String header = headers[i];
if (header == null) {
continue;
}
for (int j = 0; j < fields.length; j++) {
String field = fields[j];
if (field.equalsIgnoreCase(header)) {
name = field;
break;
}
}
}
}
if (name.isEmpty()) {
name = fields.length == 0 ? "" : fields[0];
}
}
if (name.isEmpty()) {
name = getName(target);
}
fieldName = name;
//Not a @Nested field
if (parsed != null && transformer != null) {
if (index >= 0) {
index = transformer.transformIndex(target, index);
} else if (fieldName != null) {
fieldName = transformer.transformName(target, fieldName);
}
}
}
@Override
public boolean equals(Object o) {
if (this == o) {
return true;
}
if (o == null || getClass() != o.getClass()) {
return false;
}
FieldMapping that = (FieldMapping) o;
if (index != that.index) {
return false;
}
if (!target.equals(that.target)) {
return false;
}
if (fieldName != null ? !fieldName.equals(that.fieldName) : that.fieldName != null) {
return false;
}
return beanClass.equals(that.beanClass);
}
@Override
public int hashCode() {
int result = target.hashCode();
result = 31 * result + index;
result = 31 * result + (fieldName != null ? fieldName.hashCode() : 0);
result = 31 * result + beanClass.hashCode();
return result;
}
/**
* Returns {@code true} if the field is mapped to a column index, otherwise {@code false}
*
* @return {@code true} if the field is mapped to a column index, otherwise {@code false}
*/
public boolean isMappedToIndex() {
return index >= 0;
}
/**
* Returns {@code true} if the field is mapped to a column name, otherwise {@code false}
*
* @return {@code true} if the field is mapped to a column name, otherwise {@code false}
*/
public boolean isMappedToField() {
return index < 0;
}
/**
* Returns the column index against which this field is mapped.
*
* @return the column index associated with this field, or -1 if there's no such association.
*/
public int getIndex() {
return index;
}
/**
* Defines the column name against which this field is mapped, overriding any current name derived from
* annotations or from the attribute name itself.
*
* @param fieldName the column name associated with this field
*/
public void setFieldName(String fieldName) {
this.fieldName = fieldName;
}
/**
* Returns the column name against which this field is mapped.
*
* @return the column name associated with this field, or {@code null} if there's no such association.
*/
public String getFieldName() {
return fieldName;
}
/**
* Returns the {@link Field} mapped to a column
*
* @return the {@link Field} mapped to a column
*/
public AnnotatedElement getTarget() {
return target;
}
private void setAccessible() {
if (!accessible) {
if (target instanceof Field) {
((Field) target).setAccessible(true);
} else {
((Method) target).setAccessible(true);
}
accessible = true;
}
}
/**
* Returns the parent class that contains the mapped field.
*
* @return the field's parent class
*/
public Class getFieldParent() {
return parentClass;
}
/**
* Returns the type of the mapped field
*
* @return the field type.
*/
public Class getFieldType() {
return fieldType;
}
/**
* Queries whether this field mapping can be applied over a given object instance.
*
* @param instance the object whose type will be verified in order to identify if it contains the mapped field
*
* @return {@code true} if the given instance contains the field/accessor method and can use this field mapping to modify its internal state; otherwise {@code false}
*/
public boolean canWrite(Object instance) {
if (!primitive) {
if (instance == null) {
return true;
}
return fieldType.isAssignableFrom(instance.getClass());
} else if (instance instanceof Number) {
return primitiveNumber;
} else if (instance instanceof Boolean) {
return fieldType == boolean.class;
} else if (instance instanceof Character) {
return fieldType == char.class;
}
return false;
}
/**
* Reads the value accessible by this field mapping from a given object
*
* @param instance the object whose field, mapped by this field mapping, will be read
*
* @return the value contained in the given instance's field
*/
public Object read(Object instance) {
return read(instance, false);
}
private Object read(Object instance, boolean ignoreErrors) {
setAccessible();
try {
if (readMethod != null) {
return readMethod.invoke(instance);
} else {
return ((Field) target).get(instance);
}
} catch (Throwable e) {
if (!ignoreErrors) {
throw new DataProcessingException("Unable to get value from field " + toString(), e);
}
}
return null;
}
/**
* Writes a value to the field of a given object instance, whose field is accessible through this field mapping.
*
* @param instance the object whose field will be set
* @param value the value to set on the given object's field.
*/
public void write(Object instance, Object value) {
setAccessible();
try {
if (primitive) {
if (value == null) {
if (applyDefault == null) {
Object currentValue = read(instance, true);
applyDefault = defaultPrimitiveValue.equals(currentValue);
}
if (applyDefault == Boolean.TRUE) {
value = defaultPrimitiveValue;
} else {
return;
}
} else if (defaultPrimitiveValue.getClass() != value.getClass() && value instanceof Number) {
Number number = ((Number) value);
if (fieldType == int.class) {
value = number.intValue();
} else if (fieldType == long.class) {
value = number.longValue();
} else if (fieldType == double.class) {
value = number.doubleValue();
} else if (fieldType == float.class) {
value = number.floatValue();
} else if (fieldType == byte.class) {
value = number.byteValue();
} else if (fieldType == short.class) {
value = number.shortValue();
}
}
}
if (writeMethod != null) {
writeMethod.invoke(instance, value);
} else {
((Field) target).set(instance, value);
}
} catch (Throwable e) {
if (e instanceof DataProcessingException) {
throw (DataProcessingException) e;
}
String valueTypeName = value == null ? null : value.getClass().getName();
String msg;
if (valueTypeName != null) {
msg = "Unable to set value '{value}' of type '" + valueTypeName + "' to field " + toString();
} else {
msg = "Unable to set value 'null' to field " + toString();
}
DataProcessingException ex = new DataProcessingException(msg, e);
ex.markAsNonFatal();
ex.setValue(value);
throw ex;
}
}
@Override
public String toString() {
return AnnotationHelper.describeElement(target);
}
}