#919 - io.ebean package initial

src/main/java/io/ebeaninternal/server/expression/NoopExpression.java

@@ -0,0 +1,90 @@
+package io.ebeaninternal.server.expression;
+
+import io.ebean.event.BeanQueryRequest;
+import io.ebeaninternal.api.HashQueryPlanBuilder;
+import io.ebeaninternal.api.ManyWhereJoins;
+import io.ebeaninternal.api.SpiExpression;
+import io.ebeaninternal.api.SpiExpressionRequest;
+import io.ebeaninternal.api.SpiExpressionValidation;
+import io.ebeaninternal.server.deploy.BeanDescriptor;
+
+import java.io.IOException;
+
+/**
+ * Effectively an expression that has no effect.
+ */
+class NoopExpression implements SpiExpression {
+
+  protected static final NoopExpression INSTANCE = new NoopExpression();
+
+  @Override
+  public void simplify() {
+    // do nothing
+  }
+
+  @Override
+  public SpiExpression copyForPlanKey() {
+    return this;
+  }
+
+  @Override
+  public void writeDocQuery(DocQueryContext context) throws IOException {
+  }
+
+  @Override
+  public Object getIdEqualTo(String idName) {
+    // always return null for this expression
+    return null;
+  }
+
+  @Override
+  public String nestedPath(BeanDescriptor<?> desc) {
+    return null;
+  }
+
+  @Override
+  public void containsMany(BeanDescriptor<?> desc, ManyWhereJoins whereManyJoins) {
+    // nothing to do
+  }
+
+  @Override
+  public void validate(SpiExpressionValidation validation) {
+    // always valid
+  }
+
+  @Override
+  public void prepareExpression(BeanQueryRequest<?> request) {
+    // do nothing
+  }
+
+  @Override
+  public void queryPlanHash(HashQueryPlanBuilder builder) {
+    builder.add(NoopExpression.class);
+  }
+
+  @Override
+  public int queryBindHash() {
+    // no bind values
+    return 0;
+  }
+
+  @Override
+  public void addSql(SpiExpressionRequest request) {
+    request.append("1=1");
+  }
+
+  @Override
+  public void addBindValues(SpiExpressionRequest request) {
+    // nothing to do
+  }
+
+  @Override
+  public boolean isSameByPlan(SpiExpression other) {
+    return other instanceof NoopExpression;
+  }
+
+  @Override
+  public boolean isSameByBind(SpiExpression other) {
+    return true;
+  }
+}