/*
* Copyright 2008-2020 the original author or authors.
*
* 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
*
* https://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 org.springframework.data.repository.query;
import java.util.Iterator;
import java.util.Optional;
import org.springframework.data.domain.Pageable;
import org.springframework.data.domain.Sort;
import org.springframework.data.repository.util.QueryExecutionConverters;
import org.springframework.lang.Nullable;
import org.springframework.util.Assert;
ParameterAccessor
implementation using a Parameters
instance to find special parameters. Author: Oliver Gierke, Mark Paluch
/**
* {@link ParameterAccessor} implementation using a {@link Parameters} instance to find special parameters.
*
* @author Oliver Gierke
* @author Mark Paluch
*/
public class ParametersParameterAccessor implements ParameterAccessor {
private final Parameters<?, ?> parameters;
private final Object[] values;
Creates a new ParametersParameterAccessor
. Params: - parameters – must not be null.
- values – must not be null.
/**
* Creates a new {@link ParametersParameterAccessor}.
*
* @param parameters must not be {@literal null}.
* @param values must not be {@literal null}.
*/
public ParametersParameterAccessor(Parameters<?, ?> parameters, Object[] values) {
Assert.notNull(parameters, "Parameters must not be null!");
Assert.notNull(values, "Values must not be null!");
Assert.isTrue(parameters.getNumberOfParameters() == values.length, "Invalid number of parameters given!");
this.parameters = parameters;
if (requiresUnwrapping(values)) {
this.values = new Object[values.length];
for (int i = 0; i < values.length; i++) {
this.values[i] = QueryExecutionConverters.unwrap(values[i]);
}
} else {
this.values = values;
}
}
private static boolean requiresUnwrapping(Object[] values) {
for (Object value : values) {
if (value != null && QueryExecutionConverters.supports(value.getClass())) {
return true;
}
}
return false;
}
Returns the Parameters
instance backing the accessor. Returns: the parameters will never be null.
/**
* Returns the {@link Parameters} instance backing the accessor.
*
* @return the parameters will never be {@literal null}.
*/
public Parameters<?, ?> getParameters() {
return parameters;
}
Returns the potentially unwrapped values.
Returns:
/**
* Returns the potentially unwrapped values.
*
* @return
*/
protected Object[] getValues() {
return this.values;
}
/*
* (non-Javadoc)
* @see org.springframework.data.repository.query.ParameterAccessor#getPageable()
*/
public Pageable getPageable() {
if (!parameters.hasPageableParameter()) {
return Pageable.unpaged();
}
Pageable pageable = (Pageable) values[parameters.getPageableIndex()];
return pageable == null ? Pageable.unpaged() : pageable;
}
/*
* (non-Javadoc)
* @see org.springframework.data.repository.query.ParameterAccessor#getSort()
*/
public Sort getSort() {
if (parameters.hasSortParameter()) {
Sort sort = (Sort) values[parameters.getSortIndex()];
return sort == null ? Sort.unsorted() : sort;
}
if (parameters.hasPageableParameter()) {
return getPageable().getSort();
}
return Sort.unsorted();
}
Returns the dynamic projection type if available, null otherwise. Returns:
/**
* Returns the dynamic projection type if available, {@literal null} otherwise.
*
* @return
*/
public Optional<Class<?>> getDynamicProjection() {
return Optional.ofNullable(parameters.hasDynamicProjection() //
? (Class<?>) values[parameters.getDynamicProjectionIndex()] //
: null);
}
Returns the dynamic projection type if available, null otherwise. Returns:
/**
* Returns the dynamic projection type if available, {@literal null} otherwise.
*
* @return
*/
@Nullable
public Class<?> findDynamicProjection() {
return parameters.hasDynamicProjection() //
? (Class<?>) values[parameters.getDynamicProjectionIndex()]
: null;
}
Returns the value with the given index.
Params: - index –
Returns:
/**
* Returns the value with the given index.
*
* @param index
* @return
*/
@SuppressWarnings("unchecked")
protected <T> T getValue(int index) {
return (T) values[index];
}
/*
* (non-Javadoc)
* @see org.springframework.data.repository.query.ParameterAccessor#getBindableValue(int)
*/
public Object getBindableValue(int index) {
return values[parameters.getBindableParameter(index).getIndex()];
}
/*
* (non-Javadoc)
* @see org.springframework.data.repository.query.ParameterAccessor#hasBindableNullValue()
*/
public boolean hasBindableNullValue() {
for (Parameter parameter : parameters.getBindableParameters()) {
if (values[parameter.getIndex()] == null) {
return true;
}
}
return false;
}
/*
* (non-Javadoc)
* @see org.springframework.data.repository.query.ParameterAccessor#iterator()
*/
public BindableParameterIterator iterator() {
return new BindableParameterIterator(this);
}
Iterator class to allow traversing all bindable parameters inside the accessor.
Author: Oliver Gierke
/**
* Iterator class to allow traversing all bindable parameters inside the accessor.
*
* @author Oliver Gierke
*/
private static class BindableParameterIterator implements Iterator<Object> {
private final int bindableParameterCount;
private final ParameterAccessor accessor;
private int currentIndex = 0;
Creates a new BindableParameterIterator
. Params: - accessor – must not be null.
/**
* Creates a new {@link BindableParameterIterator}.
*
* @param accessor must not be {@literal null}.
*/
public BindableParameterIterator(ParametersParameterAccessor accessor) {
Assert.notNull(accessor, "ParametersParameterAccessor must not be null!");
this.accessor = accessor;
this.bindableParameterCount = accessor.getParameters().getBindableParameters().getNumberOfParameters();
}
Returns the next bindable parameter.
Returns:
/**
* Returns the next bindable parameter.
*
* @return
*/
public Object next() {
return accessor.getBindableValue(currentIndex++);
}
/*
* (non-Javadoc)
* @see java.util.Iterator#hasNext()
*/
public boolean hasNext() {
return bindableParameterCount > currentIndex;
}
/*
* (non-Javadoc)
* @see java.util.Iterator#remove()
*/
public void remove() {
throw new UnsupportedOperationException();
}
}
}