com.avaje.ebeaninternal.server.expression.DefaultExampleExpression Maven / Gradle / Ivy
package com.avaje.ebeaninternal.server.expression;
import com.avaje.ebean.ExampleExpression;
import com.avaje.ebean.LikeType;
import com.avaje.ebean.bean.EntityBean;
import com.avaje.ebean.event.BeanQueryRequest;
import com.avaje.ebeaninternal.api.HashQueryPlanBuilder;
import com.avaje.ebeaninternal.api.ManyWhereJoins;
import com.avaje.ebeaninternal.api.SpiExpression;
import com.avaje.ebeaninternal.api.SpiExpressionRequest;
import com.avaje.ebeaninternal.api.SpiExpressionValidation;
import com.avaje.ebeaninternal.server.deploy.BeanDescriptor;
import com.avaje.ebeaninternal.server.deploy.BeanProperty;
import com.avaje.ebeaninternal.server.deploy.BeanPropertyAssocOne;
import com.avaje.ebeaninternal.server.query.SplitName;
import java.io.IOException;
import java.util.ArrayList;
/**
* A "Query By Example" type of expression.
*
* Pass in an example entity and for each non-null scalar properties an
* expression is added.
*
*
*
{@code
* // create an example bean and set the properties
* // with the query parameters you want
* Customer example = new Customer();
* example.setName("Rob%");
* example.setNotes("%something%");
*
* List list = Ebean.find(Customer.class)
* .where()
* .exampleLike(example)
* .findList();
*
* }
*/
public class DefaultExampleExpression implements SpiExpression, ExampleExpression {
/**
* The example bean containing the properties.
*/
private final EntityBean entity;
/**
* Set to true to use case insensitive expressions.
*/
private boolean caseInsensitive;
/**
* The type of like (RAW, STARTS_WITH, ENDS_WITH etc)
*/
private LikeType likeType;
/**
* By default zeros are excluded.
*/
private boolean includeZeros;
/**
* The non null bean properties and found and together added as a list of
* expressions (like or equal to expressions).
*/
private ArrayList list;
/**
* Construct the query by example expression.
*
* @param entity the example entity with non null property values
* @param caseInsensitive if true use case insensitive expressions
* @param likeType the type of Like wild card used
*/
public DefaultExampleExpression(EntityBean entity, boolean caseInsensitive, LikeType likeType) {
this.entity = entity;
this.caseInsensitive = caseInsensitive;
this.likeType = likeType;
}
DefaultExampleExpression(ArrayList source) {
this.entity = null;
this.list = new ArrayList(source.size());
for (SpiExpression expression : source) {
list.add(expression.copyForPlanKey());
}
}
@Override
public void simplify() {
// do nothing
}
@Override
public void writeDocQuery(DocQueryContext context) throws IOException {
if (!list.isEmpty()) {
context.startBoolMust();
for (SpiExpression expr : list) {
expr.writeDocQuery(context);
}
context.endBool();
}
}
@Override
public Object getIdEqualTo(String idName) {
// always return null for this expression
return null;
}
@Override
public SpiExpression copyForPlanKey() {
return new DefaultExampleExpression(list);
}
@Override
public String nestedPath(BeanDescriptor desc) {
return null;
}
@Override
public void containsMany(BeanDescriptor desc, ManyWhereJoins whereManyJoins) {
list = buildExpressions(desc);
if (list != null) {
for (int i = 0; i < list.size(); i++) {
list.get(i).containsMany(desc, whereManyJoins);
}
}
}
@Override
public void prepareExpression(BeanQueryRequest request) {
// do nothing
}
@Override
public ExampleExpression includeZeros() {
includeZeros = true;
return this;
}
@Override
public ExampleExpression caseInsensitive() {
caseInsensitive = true;
return this;
}
@Override
public ExampleExpression useStartsWith() {
likeType = LikeType.STARTS_WITH;
return this;
}
@Override
public ExampleExpression useContains() {
likeType = LikeType.CONTAINS;
return this;
}
@Override
public ExampleExpression useEndsWith() {
likeType = LikeType.ENDS_WITH;
return this;
}
@Override
public ExampleExpression useEqualTo() {
likeType = LikeType.EQUAL_TO;
return this;
}
@Override
public void validate(SpiExpressionValidation validation) {
for (int i = 0; i < list.size(); i++) {
list.get(i).validate(validation);
}
}
/**
* Adds bind values to the request.
*/
@Override
public void addBindValues(SpiExpressionRequest request) {
for (int i = 0; i < list.size(); i++) {
SpiExpression item = list.get(i);
item.addBindValues(request);
}
}
/**
* Generates and adds the sql to the request.
*/
@Override
public void addSql(SpiExpressionRequest request) {
if (!list.isEmpty()) {
request.append("(");
for (int i = 0; i < list.size(); i++) {
SpiExpression item = list.get(i);
if (i > 0) {
request.append(" and ");
}
item.addSql(request);
}
request.append(") ");
}
}
/**
* Return a hash for AutoTune query identification.
*/
@Override
public void queryPlanHash(HashQueryPlanBuilder builder) {
builder.add(DefaultExampleExpression.class);
for (int i = 0; i < list.size(); i++) {
list.get(i).queryPlanHash(builder);
}
}
/**
* Return a hash for the actual bind values used.
*/
@Override
public int queryBindHash() {
int hc = DefaultExampleExpression.class.getName().hashCode();
for (int i = 0; i < list.size(); i++) {
hc = hc * 31 + list.get(i).queryBindHash();
}
return hc;
}
@Override
public boolean isSameByPlan(SpiExpression other) {
if (!(other instanceof DefaultExampleExpression)) {
return false;
}
DefaultExampleExpression that = (DefaultExampleExpression) other;
if (this.list.size() != that.list.size()) {
return false;
}
for (int i = 0; i < list.size(); i++) {
if (!list.get(i).isSameByPlan(that.list.get(i))) {
return false;
}
}
return true;
}
@Override
public boolean isSameByBind(SpiExpression other) {
DefaultExampleExpression that = (DefaultExampleExpression) other;
if (this.list.size() != that.list.size()) {
return false;
}
for (int i = 0; i < list.size(); i++) {
if (!list.get(i).isSameByBind(that.list.get(i))) {
return false;
}
}
return true;
}
/**
* Build the List of expressions.
*/
private ArrayList buildExpressions(BeanDescriptor beanDescriptor) {
ArrayList list = new ArrayList();
addExpressions(list, beanDescriptor, entity, null);
return list;
}
/**
* Add expressions to the list for all the non-null properties (and do this recursively).
*/
private void addExpressions(ArrayList list, BeanDescriptor beanDescriptor, EntityBean bean, String prefix) {
for (BeanProperty beanProperty : beanDescriptor.propertiesAll()) {
if (!beanProperty.isTransient()) {
Object value = beanProperty.getValue(bean);
if (value != null) {
String propName = SplitName.add(prefix, beanProperty.getName());
if (beanProperty.isScalar()) {
if (value instanceof String) {
list.add(new LikeExpression(propName, (String) value, caseInsensitive, likeType));
} else {
// exclude the zero values typically to weed out
// primitive int and long that initialise to 0
if (includeZeros || !isZero(value)) {
list.add(new SimpleExpression(propName, Op.EQ, value));
}
}
} else if ((beanProperty instanceof BeanPropertyAssocOne) && (value instanceof EntityBean)) {
BeanPropertyAssocOne assocOne = (BeanPropertyAssocOne) beanProperty;
BeanDescriptor targetDescriptor = assocOne.getTargetDescriptor();
addExpressions(list, targetDescriptor, (EntityBean) value, propName);
}
}
}
}
}
/**
* Return true if the value is a numeric zero.
*/
private boolean isZero(Object value) {
if (value instanceof Number) {
Number num = (Number) value;
double doubleValue = num.doubleValue();
if (doubleValue == 0) {
return true;
}
}
return false;
}
}